@article{langerhans_goins_stemp_riesch_araujo_layman_2021, title={Consuming Costly Prey: Optimal Foraging and the Role of Compensatory Growth}, volume={8}, ISSN={["2296-701X"]}, DOI={10.3389/fevo.2020.603387}, abstractNote={Some prey are exceptionally difficult to digest, and yet even non-specialized animals may consume them—why? Durophagy, the consumption of hard-shelled prey, is thought to require special adaptations for crushing or digesting the hard shells to avoid the many potential costs of this prey type. But many animals lacking specializations nevertheless include hard-bodied prey in their diets. We describe several non-mutually exclusive adaptive mechanisms that could explain such a pattern, and point to optimal foraging and compensatory growth as potentially having widespread importance in explaining costly-prey consumption. We first conducted a literature survey to quantify the regularity with which non-specialized teleost fishes consume hard-shelled prey: stomach-content data from 325 teleost fish species spanning 82 families (57,233 stomach samples) demonstrated that non-specialized species comprise ~75% of the total species exhibiting durophagy, commonly consuming hard-shelled prey at low to moderate levels (~10–40% as much as specialists). We then performed a diet survey to assess the frequency of molluscivory across the native latitudinal range of a small livebearing fish, Gambusia holbrooki, lacking durophagy specializations. Molluscivory was regionally widespread, spanning their entire native latitudinal range (>14° latitude). Third, we tested for a higher frequency of molluscivory under conditions of higher intraspecific resource competition in Bahamian mosquitofish (Gambusia spp.). Examining over 5,300 individuals, we found that molluscivory was more common in populations with higher population density, suggesting that food limitation is important in eliciting molluscivory. Finally, we experimentally tested in G. holbrooki whether molluscivory reduces growth rate and whether compensatory growth follows a period of molluscivory. We found that consumption of hard-shelled gastropods results in significantly reduced growth rate, but compensatory growth following prior snail consumption can quickly mitigate growth costs. Our results suggest that the widespread phenomenon of costly-prey consumption may be partially explained by its relative benefits when few alternative prey options exist, combined with compensatory growth that alleviates temporary costs.}, journal={FRONTIERS IN ECOLOGY AND EVOLUTION}, author={Langerhans, Randall Brian and Goins, Taylor R. and Stemp, Kenzi M. and Riesch, Rudiger and Araujo, Marcio S. and Layman, Craig A.}, year={2021}, month={Mar} } @article{bogdanoff_shertzer_layman_chapman_fruitema_solomon_sabattis_green_morris_2021, title={Optimum lionfish yield: a non-traditional management concept for invasive lionfish (Pterois spp.) fisheries}, volume={23}, ISSN={["1573-1464"]}, DOI={10.1007/s10530-020-02398-z}, number={3}, journal={BIOLOGICAL INVASIONS}, author={Bogdanoff, Alex K. and Shertzer, Kyle W. and Layman, Craig A. and Chapman, Jennifer K. and Fruitema, Marc L. and Solomon, Jennifer and Sabattis, Julie and Green, Stephanie and Morris, James A., Jr.}, year={2021}, month={Mar}, pages={795–810} } @article{maurer_seminoff_layman_stapleton_godfrey_reiskind_2021, title={Population Viability of Sea Turtles in the Context of Global Warming}, volume={71}, ISSN={["1525-3244"]}, DOI={10.1093/biosci/biab028}, abstractNote={Abstract}, number={8}, journal={BIOSCIENCE}, author={Maurer, Andrew S. and Seminoff, Jeffrey A. and Layman, Craig A. and Stapleton, Seth P. and Godfrey, Matthew H. and Reiskind, Martha O. Burford}, year={2021}, month={Aug}, pages={790–804} } @misc{layman_allgeier_2020, title={An ecosystem ecology perspective on artificial reef production}, volume={57}, ISSN={["1365-2664"]}, DOI={10.1111/1365-2664.13748}, abstractNote={Abstract}, number={11}, journal={JOURNAL OF APPLIED ECOLOGY}, author={Layman, Craig A. and Allgeier, Jacob E.}, year={2020}, month={Nov}, pages={2139–2148} } @article{archer_kahn_thiess_law_leys_johannessen_layman_burke_dunham_2020, title={Foundation Species Abundance Influences Food Web Topology on Glass Sponge Reefs}, volume={7}, ISBN={2296-7745}, DOI={10.3389/fmars.2020.549478}, abstractNote={Foundation species support communities across a wide range of ecosystems. Non-trophic interactions are considered the primary way foundation species influence communities, with their trophic interactions having little impact on community structure. Here we assess the relative trophic importance of a foundation species and assess how its abundance can influence food web topology. Using empirical data and published trophic interactions we built food web models for 20 glass sponge reefs to examine how average live reef-building sponge abundance (proxied by percent cover) at the reef level is correlated with community structure and food web network topology. Then, using a generalized food web model and stable isotope data we examined the relative importance of sponges. Sponges were consumed by all species examined and contributed significantly to their diets. Additionally, sponges were the second most important node in our generalized reef food web. Several metrics of food web topology (connectance, clustering, and median degree) and community structure exhibited a threshold response to reef-building sponge cover, with the change point occurring between 8 and 13% live sponge cover. Below this threshold, as average sponge cover increases, the consumers observed on a reef rely on fewer sources and are consumed by fewer predators, resulting in food webs that are more clustered and less connected. Above the threshold, as average sponge cover increases, the reefs’ food webs are less clustered and more connected, with consumers utilizing more sources and having more predators. This corresponds with the finding that several generalist predators (e.g., rockfishes) are associated with high sponge cover reefs. Our results are not consistent with previous reports that increasing foundation species abundance decreases connectance in food webs. We propose that the influence of foundation species on food web topology may be dependent on palatability, and therefore relative trophic importance, of the foundation species. Finally, our findings have important implications for sponge reef conservation and management, as they suggest that reefs below the 10% sponge cover threshold support different communities than high live sponge cover reefs.}, journal={FRONTIERS IN MARINE SCIENCE}, author={Archer, Stephanie K. and Kahn, Amanda S. and Thiess, Mary and Law, Lauren and Leys, Sally P. and Johannessen, Sophia C. and Layman, Craig A. and Burke, Lily and Dunham, Anya}, year={2020} } @article{allgeier_cline_walsworth_wathen_layman_schindler_2020, title={Individual behavior drives ecosystem function and the impacts of harvest}, volume={6}, ISSN={["2375-2548"]}, DOI={10.1126/sciadv.aax8329}, abstractNote={Individual fish behavior has large and unpredictable impacts on ecosystem nutrient dynamics with implications for species harvest.}, number={9}, journal={SCIENCE ADVANCES}, author={Allgeier, Jacob E. and Cline, Timothy J. and Walsworth, Timothy E. and Wathen, Gus and Layman, Craig A. and Schindler, Daniel E.}, year={2020}, month={Feb} } @article{allgeier_andskog_hensel_appaldo_layman_kemp_2020, title={Rewiring coral: Anthropogenic nutrients shift diverse coral-symbiont nutrient and carbon interactions toward symbiotic algal dominance}, volume={26}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.15230}, abstractNote={Abstract}, number={10}, journal={GLOBAL CHANGE BIOLOGY}, author={Allgeier, Jacob E. and Andskog, Mona A. and Hensel, Enie and Appaldo, Richard and Layman, Craig and Kemp, Dustin W.}, year={2020}, month={Oct}, pages={5588–5601} } @article{allgeier_wenger_layman_2020, title={Taxonomic identity best explains variation in body nutrient stoichiometry in a diverse marine animal community}, volume={10}, ISSN={["2045-2322"]}, DOI={10.1038/s41598-020-67881-y}, abstractNote={Abstract}, number={1}, journal={SCIENTIFIC REPORTS}, author={Allgeier, Jacob E. and Wenger, Seth and Layman, Craig A.}, year={2020}, month={Aug} } @article{rossi_archer_giri_layman_2020, title={The role of multiple stressors in a dwarf red mangrove (Rhizophora mangle) dieback}, volume={237}, ISSN={["1096-0015"]}, DOI={10.1016/j.ecss.2020.106660}, abstractNote={Mangroves are habitat-forming foundation species that provide the framework for entire coastal communities. Unfortunately, mangrove forests are declining globally, often due to multiple stressors. We report a recent mangrove dieback on Abaco Island, The Bahamas, that appears to be the result of multiple stressors. First, we investigated the role of hurricane and drought events in relation to green vegetation in the dieback area, as measured using Normalized Difference Vegetation Index (NDVI). We used historical Landsat imagery of the dieback region from 1989 to 2013 to identify changes in green vegetation and to determine when the dieback likely began. We determined that the dieback began around 2008, but found little evidence of a relationship between NDVI and hurricane or drought events, particularly in relation to the estimated start of the dieback. Preliminary observations in the dieback area suggested grazing by leaf-chewing organisms and disease were both present at high levels. We surveyed individual mangrove trees to determine the intensity of leaf-chewing herbivory and foliar disease on mangroves in the dieback area. We found leaf-chewing herbivory ranged from 0 to 79%, with a mean of 29% of leaves chewed per tree and disease incidence ranged from 0% to 97% with a mean of 47%. Finally, we conducted a simulated grazing experiment to test if experimental opening mimicking grazing could facilitate disease infection in mangroves . Experimental opening of plant tissues showed that grazing can increase disease. Our results suggest that drought and hurricanes did not initiate this dieback, but that herbivory likely facilitated the spread of disease thereby contributing to the dieback.}, journal={ESTUARINE COASTAL AND SHELF SCIENCE}, author={Rossi, R. E. and Archer, S. K. and Giri, C. and Layman, C. A.}, year={2020}, month={May} } @misc{giery_layman_2019, title={Ecological Consequences Of Sexually Selected Traits: An Eco-Evolutionary Perspective}, volume={94}, ISSN={["1539-7718"]}, DOI={10.1086/702341}, abstractNote={Evolution is rapidly gaining attention as an important driver of ecological process. Yet, evolution via sexual selection has generally been omitted from this emerging synthesis. Our goal in this paper is to illustrate causative links by which sexually selected traits affect fundamental ecological interactions and processes. We summarize evidence, primarily from vertebrate studies under field conditions, which shows: sexually selected traits have ecological effects; and that their evolution has diverse influences on ecological systems. We conclude with a brief discussion of future research directions to encourage study of sexual selection from a more integrative and eco-evolutionary perspective.}, number={1}, journal={QUARTERLY REVIEW OF BIOLOGY}, author={Giery, Sean T. and Layman, Craig A.}, year={2019}, month={Mar}, pages={29–74} } @article{hensel_allgeier_layman_2019, title={Effects of predator presence and habitat complexity on reef fish communities in The Bahamas}, volume={166}, ISSN={["1432-1793"]}, DOI={10.1007/s00227-019-3568-3}, number={10}, journal={MARINE BIOLOGY}, author={Hensel, Enie and Allgeier, Jacob E. and Layman, Craig A.}, year={2019}, month={Oct} } @article{lyon_eggleston_bohnenstiehl_layman_ricci_allgeier_2019, title={Fish community structure, habitat complexity, and soundscape characteristics of patch reefs in a tropical, back-reef system}, volume={609}, ISSN={["1616-1599"]}, url={http://dx.doi.org/10.3354/meps12829}, DOI={10.3354/meps12829}, abstractNote={Fig. S1. Box plots for nightly low frequency (0.1 – 1.5 kHz) SPL (a) and high frequency (4 – 20 kHz) SPL (b) for reef 5 for each lunar quarter. Red lines indicate median SPLs, ticks indicate maximum and minimum values, horizontal blue lines indicate 75% and 25% quantiles, and angled blue lines indicate the 95% upper and lower confidence levels in the median. Kruskal-Wallis tests were used to test for differences in SPL between lunar quarters. Relationships between water temperature (in C) and low frequency (0.1 – 1.5 kHz) SPL (c) and high frequency (4 – 20 kHz) SPL (d) were evaluated using linear regression models. 2 = 2.52 p = 0.47}, journal={MARINE ECOLOGY PROGRESS SERIES}, publisher={Inter-Research Science Center}, author={Lyon, R. Patrick and Eggleston, David B. and Bohnenstiehl, DelWayne R. and Layman, Craig A. and Ricci, Shannon W. and Allgeier, Jacob E.}, year={2019}, month={Jan}, pages={33–48} } @article{bogdanoff_mostowy_peake_layman_bermudez_baca_palacios_gonzalez_del rocio bravo xicoténcatl_morris_2018, title={A brief description of invasive lionfish (Pterois sp.) diet composition in the Arrecifes de Cozumel National Park}, volume={17}, ISSN={2352-2496}, url={http://dx.doi.org/10.1016/J.FOOWEB.2018.E00104}, DOI={10.1016/J.FOOWEB.2018.E00104}, abstractNote={Invasive lionfish (Pterois sp.) have the potential to affect reef communities in the western Atlantic through predation on native species. Lionfish are opportunistic generalist carnivores whose diet varies significantly among locations due to differences in local prey assemblages. As such, site-specific diet studies are needed to better inform local research and monitoring. The objective of this study was to describe lionfish diet in the Arrecifes de Cozumel National Park (ACNP), an ecologically and economically important marine protected area along the eastern Yucatan Peninsula. Through the analysis 343 lionfish stomachs, we determined that 1) species of the genera Sparisoma, Stegastes, Bothus, Haemulon, and Serranus are the most important prey to lionfish diet in the ACNP, 2) lionfish in the ACNP transition from a shrimp to a fish dominated diet through ontogeny, and 3) the contribution of crabs to lionfish diet in the ACNP is the largest observed in the western Atlantic to date. The data presented here can be used to inform research and monitoring efforts in and around the ACNP.}, journal={Food Webs}, publisher={Elsevier BV}, author={Bogdanoff, Alex K. and Mostowy, Jason and Peake, Jonathan and Layman, Craig A. and Bermudez, Abelardo Brito and Baca, Cristopher Gonzalez and Palacios, Nallely Hernández and Gonzalez, Diana Tamara Martinez and Del Rocio Bravo Xicoténcatl, Maria and Morris, James A., Jr.}, year={2018}, month={Dec}, pages={e00104} } @article{archer_hensel_layman_2018, title={Ambient nutrient availability drives the outcome of an interaction between a sponge (Halichondria melanadocia) and seagrass (Thalassia testudinum)}, volume={503}, ISSN={["1879-1697"]}, DOI={10.1016/j.jembe.2018.02.005}, abstractNote={Nutrient loading is a common human impact in coastal habitats which is driving significant losses of seagrass habitat worldwide. This is concerning, as seagrass beds provide numerous ecosystem services. Although nutrient loading can result in eutrophication and mass mortality of seagrasses, it more often results in subtle alterations of abiotic conditions which, by themselves, are insufficient to drive widespread seagrass mortality. Here we used a month-long field-based experiment to test the influence of anthropogenic nutrient loading on the outcome of an interaction between an epizootic sponge (Halichondria melanadocia) and a seagrass (Thalassia testudinum). Using a factorial design we manipulated ambient nutrient concentrations by adding fertilizer to plots with and without a sponge in a relatively pristine seagrass bed on Abaco Island, The Bahamas. We measured seagrass growth, below- and above-ground biomass, and the change in shoot density. We found that low levels of nutrient loading (i.e., insufficient to cause increased algal growth and decreased oxygen levels associated with eutrophication) resulted in a non-significant increase in seagrass growth, biomass, and shoot density when a sponge was absent. When a sponge was present, the same level of fertilization resulted in a significant reduction in the response variables. Our results show that anthropogenic nutrient loading can shift the sponge-seagrass interaction away from commensalism toward an interaction that has negative consequences for the seagrass. Additionally, a shift in the outcome of this context-dependent interaction can alter the impact of nutrient loading on seagrass productivity. Our study provides an example of how simple classifications of interspecific interactions (e.g., commensalism) often mask underlying variability. Characterizing the mechanisms driving the variability will allow us to understand when and how the outcome of an interaction will change. Ultimately, this will allow us to better predict how human activities will indirectly impact various ecosystem functions.}, journal={JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY}, author={Archer, Stephanie K. and Hensel, Enie and Layman, Craig A.}, year={2018}, month={Jun}, pages={86–91} } @article{allgeier_layman_montaña_hensel_appaldo_rosemond_2018, title={Anthropogenic versus fish-derived nutrient effects on seagrass community structure and function}, volume={99}, ISSN={0012-9658}, url={http://dx.doi.org/10.1002/ECY.2388}, DOI={10.1002/ECY.2388}, abstractNote={Abstract}, number={8}, journal={Ecology}, publisher={Wiley}, author={Allgeier, Jacob E. and Layman, Craig A. and Montaña, Carmen G. and Hensel, Enie and Appaldo, Richard and Rosemond, Amy D.}, year={2018}, month={Jul}, pages={1792–1801} } @article{henson_aday_rice_layman_2018, title={Assessing the Influence of Tilapia on Sport Fish Species in North Carolina Reservoirs}, volume={147}, ISSN={["1548-8659"]}, DOI={10.1002/tafs.10031}, abstractNote={Abstract}, number={2}, journal={TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY}, author={Henson, Mary Nell and Aday, D. Derek and Rice, James A. and Layman, Craig A.}, year={2018}, month={Mar}, pages={350–362} } @article{peake_bogdanoff_layman_castillo_reale-munroe_chapman_dahl_patterson_eddy_ellis_et al._2018, title={Feeding ecology of invasive lionfish (Pterois volitans and Pterois miles) in the temperate and tropical western Atlantic}, volume={20}, ISSN={["1573-1464"]}, DOI={10.1007/s10530-018-1720-5}, abstractNote={Numerous location-based diet studies have been published describing different aspects of invasive lionfish (Pterois volitans and Pterois miles) feeding ecology, but there has been no synthesis of their diet composition and feeding patterns across regional gradients. 8125 lionfish stomachs collected from 10 locations were analyzed to provide a generalized description of their feeding ecology at a regional scale and to compare their diet among locations. Our regional data indicate lionfish in the western Atlantic are opportunistic generalist carnivores that consume at least 167 vertebrate and invertebrate prey species across multiple trophic guilds, and carnivorous fish and shrimp prey that are not managed fishery species and not considered at risk of extinction by the International Union for Conservation of Nature disproportionately dominate their diet. Correlations between lionfish size and their diet composition indicate lionfish in the western Atlantic transition from a shrimp-dominated diet to a fish-dominated diet through ontogeny. Lionfish total length (TL) (mm) was found to predict mean prey mass per stomach (g) by the following equation mean prey mass =0.0002*TL1.6391, which can be used to estimate prey biomass consumption from lionfish length-frequency data. Our locational comparisons indicate lionfish diet varies considerably among locations, even at the group (e.g., crab) and trophic guild levels. The Modified Index of Relative Importance developed specifically for this study, calculated as the frequency of prey a × the number of prey a, can be used in other diet studies to assess prey importance when prey mass data are not available. Researchers and managers can use the diet data presented in this study to make inference about lionfish feeding ecology in areas where their diet has yet to be described. These data can be used to guide research and monitoring efforts, and can be used in modeling exercises to simulate the potential effects of lionfish on marine food webs. Given the large variability in lionfish diet composition among locations, this study highlights the importance of continued location-based diet assessments to better inform local management activities.}, number={9}, journal={BIOLOGICAL INVASIONS}, author={Peake, Jonathan and Bogdanoff, Alex K. and Layman, Craig A. and Castillo, Bernard and Reale-Munroe, Kynoch and Chapman, Jennifer and Dahl, Kristen and Patterson, William F., III and Eddy, Corey and Ellis, Robert D. and et al.}, year={2018}, month={Sep}, pages={2567–2597} } @article{kenworthy_grabowski_layman_sherwood_powers_peterson_gittman_keller_fodrie_2018, title={Movement ecology of a mobile predatory fish reveals limited habitat linkages within a temperate estuarine seascape}, volume={75}, ISSN={["1205-7533"]}, DOI={10.1139/cjfas-2017-0308}, abstractNote={ Large predatory fishes, capable of traveling great distances, can facilitate energy flow linkages among spatially separated habitat patches via extended foraging behaviors over expansive areas. Here, we tested this concept by tracking the movement of a large mobile estuarine fish, red drum (Sciaenops ocellatus). Specifically, we addressed the following two questions: (i) What are the spatial and temporal patterns of red drum movement (rates of dispersal) and activity space? (ii) Does red drum movement facilitate linkages among estuarine marsh complexes? Dispersal from the release location was greatest during the first 2 weeks at liberty before declining to less than 0.5 km·week–1 for the remainder of the study. Activity space initially increased rapidly before reaching an asymptote at 2.5 km2 2 weeks postrelease. Connectivity indices calculated among marsh complexes corroborated these observations, suggesting high residency and limited seascape-scale linkages via red drum movement behaviors. These data highlight potential within-estuary spatial structure for mobile fishes and could inform subsequent efforts to track energy flows in coastal food webs, predict the footprint of local habitat restoration benefits, and enhance the design of survey regimes to quantify overall population demography. }, number={11}, journal={CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES}, author={Kenworthy, Matthew D. and Grabowski, Jonathan H. and Layman, Craig A. and Sherwood, Graham D. and Powers, Sean P. and Peterson, Charles H. and Gittman, Rachel K. and Keller, Danielle A. and Fodrie, F. Joel}, year={2018}, month={Nov}, pages={1990–1998} } @misc{olds_vargas-fonseca_connolly_gilby_huijbers_hyndes_layman_whitfield_schlacher_2018, title={The ecology of fish in the surf zones of ocean beaches: A global review}, volume={19}, ISSN={["1467-2979"]}, DOI={10.1111/faf.12237}, abstractNote={Abstract}, number={1}, journal={FISH AND FISHERIES}, author={Olds, Andrew D. and Vargas-Fonseca, Elena and Connolly, Rod M. and Gilby, Ben L. and Huijbers, Chantal M. and Hyndes, Glenn A. and Layman, Craig A. and Whitfield, Alan K. and Schlacher, Thomas A.}, year={2018}, month={Jan}, pages={78–89} } @article{hensel_wenclawski_layman_2018, title={Using a small, consumer-grade drone to identify and count marine megafauna in shallow habitats}, volume={46}, ISSN={["0717-7178"]}, DOI={10.3856/vol46-issue5-fulltext-15}, abstractNote={Large-bodied animals, megafauna, are disproportionately threatened and yet, remain relatively difficult to monitor, particularly true in the ocean. Consumer-grade drones have high definition imagery and offer a non-invasive way to monitor a subset of marine megafauna, especially those species that spend part of their life near the water’s surface. However, a key question is the extent to which drone imagery data offer reliable abundance estimates due to potential detection restraints, and the ability to compare data from different locations. Here we tested the efficacy of a quadcopter drone to collect megafauna abundance data in multiple shallow-water habitats in the realistic background variation of shoreline development. On Great Abaco Island, The Bahamas we repeated drone surveys in nearshore habitats from June to August 2015 at three paired high and low human population sites. We tested the drone's detection probability using decoy organisms and found no effect of water quality or benthic characteristics on detectability. In short, the drones appear to work to monitor these species. We also noted patterns in the occupancy of the species on which we focused. We observed three shark, two ray, and two sea turtle species, finding higher abundances of all species in our low human population sites compared to high human population sites. Our results highlight the ability of consumer-grade drones to estimate the abundance and distribution of large-bodied elasmobranchs and sea turtles in shallow water habitats. Further, our study supports their capability to evaluate issues related to the conservation and management of nearshore ecosystems.}, number={5}, journal={LATIN AMERICAN JOURNAL OF AQUATIC RESEARCH}, author={Hensel, Enie and Wenclawski, Stephanie and Layman, Craig A.}, year={2018}, month={Nov}, pages={1025–1033} } @article{archer_stevens_rossi_matterson_layman_2017, title={Abiotic conditions drive significant variability in nutrient processing by a common Caribbean sponge, Ircinia felix}, volume={62}, ISSN={["1939-5590"]}, DOI={10.1002/lno.10533}, abstractNote={Abstract}, number={4}, journal={LIMNOLOGY AND OCEANOGRAPHY}, author={Archer, Stephanie K. and Stevens, Julia L. and Rossi, Ryann E. and Matterson, Kenan O. and Layman, Craig A.}, year={2017}, month={Jul}, pages={1783–1793} } @misc{allgeier_burkepile_layman_2017, title={Animal pee in the sea: consumer-mediated nutrient dynamics in the world's changing oceans}, volume={23}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.13625}, abstractNote={Abstract}, number={6}, journal={GLOBAL CHANGE BIOLOGY}, author={Allgeier, Jacob E. and Burkepile, Deron E. and Layman, Craig A.}, year={2017}, month={Jun}, pages={2166–2178} } @article{araujo_layman_langerhans_2017, title={Body streamlining is related to higher growth in Bahamian mosquitofish}, volume={18}, number={4}, journal={Evolutionary Ecology Research}, author={Araujo, M. S. and Layman, C. A. and Langerhans, R. B.}, year={2017}, pages={383–391} } @article{rossi_giery_bonnema_todd_layman_2017, title={Characterizing trophic ecology of the checkered puffer (Sphoeroides testudineus)}, volume={45}, ISSN={["0717-7178"]}, DOI={10.3856/vol45-issue5-fulltext-24}, abstractNote={Sphoeroides testudineus (Linnaeus, 1758), is a common, widely distributed fish in coastal ecosystems. To better understand the trophic niche of S. testudineus, we collected individuals from tidal creeks on Abaco Island, The Bahamas, and employed stomach content and stable isotope analysis. Examination of stomach contents showed that mollusks, such as West Indian false cerith snails, cerith snails, and tellin clams, were the most common prey items. Diet data were consistent with stable isotopes data such that S. testudineus seem to feed at an intermediate trophic position in the food web. These preliminary data suggest that S. testudineus may be a critical intermediate link in these wetland food webs, serving as pathways through which energy is transferred from primary consumers to other predator species.}, number={5}, journal={LATIN AMERICAN JOURNAL OF AQUATIC RESEARCH}, author={Rossi, Ryann E. and Giery, Sean T. and Bonnema, Erika W. and Todd, Allison L. and Layman, Craig A.}, year={2017}, month={Nov}, pages={1075–1078} } @article{giery_layman_2017, title={Dissolved organic carbon and unimodal variation in sexual signal coloration in mosquitofish: a role for light limitation?}, volume={284}, ISSN={["1471-2954"]}, DOI={10.1098/rspb.2017.0163}, abstractNote={Natural selection plays an important role in the evolution of sexual communication systems. Here, we assess the effect of two well-known selection agents, transmission environment and predation, on interpopulation variation in sexual signals. Our model system is a series of 21 populations of Bahamian mosquitofish subjected to independent variation in optical conditions and predation risk. We show that optically diverse environments, caused by locally variable dissolved organic carbon concentrations, rather than spatial variation in predation, drove divergence in fin coloration (fin redness). We found a unimodal pattern of phenotypic variation along the optical gradient indicating a threshold-type response of visual signals to broad variation in optical conditions. We discuss evolutionary and ecological mechanisms that may drive such a pattern as well as the implications of non-monotonic clines for evolutionary differentiation.}, number={1852}, journal={PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES}, author={Giery, Sean T. and Layman, Craig A.}, year={2017}, month={Apr} } @article{layman_2017, title={Editorial}, volume={10}, ISSN={2352-2496}, url={http://dx.doi.org/10.1016/J.FOOWEB.2016.11.001}, DOI={10.1016/J.FOOWEB.2016.11.001}, journal={Food Webs}, publisher={Elsevier BV}, author={Layman, C.A.}, year={2017}, month={Mar}, pages={1} } @article{sweatman_layman_fourqurean_2017, title={Habitat fragmentation has some impacts on aspects of ecosystem functioning in a sub-tropical seagrass bed}, volume={126}, ISSN={["1879-0291"]}, DOI={10.1016/j.marenvres.2017.02.003}, abstractNote={Habitat fragmentation impacts ecosystem functioning in many ways, including reducing the availability of suitable habitat for animals and altering resource dynamics. Fragmentation in seagrass ecosystems caused by propeller scarring is a major source of habitat loss, but little is known about how scars impact ecosystem functioning. Propeller scars were simulated in seagrass beds of Abaco, Bahamas, to explore potential impacts. To determine if plant-herbivore interactions were altered by fragmentation, amphipod grazers were excluded from half the experimental plots, and epiphyte biomass and community composition were compared between grazer control and exclusion plots. We found a shift from light limitation to phosphorus limitation at seagrass patch edges. Fragmentation did not impact top-down control on epiphyte biomass or community composition, despite reduced amphipod density in fragmented habitats. Seagrass and amphipod responses to propeller scarring suggest that severely scarred seagrass beds could be subject to changes in internal nutrient stores and amphipod distribution.}, journal={MARINE ENVIRONMENTAL RESEARCH}, author={Sweatman, Jennifer L. and Layman, Craig A. and Fourqurean, James W.}, year={2017}, month={May}, pages={95–108} } @article{pinheiro_layman_castello_leite_2017, title={Trophic role of demersal mesopredators on rocky reefs in an equatorial Atlantic Ocean island}, volume={33}, ISSN={["1439-0426"]}, DOI={10.1111/jai.13204}, abstractNote={Summary The decrease in the number of sharks around Saint Peter and Saint Paul Archipelago (SPSPA) may impact food web structure. We investigated trophic relationships in the shallow rocky reefs of the SPSPA using stable isotopes and stomach contents with a particular focus on three abundant mesopredators: Caranx lugubris, Enchelycore nigricans and Muraena pavonina. Food web structure was described using samples of the most abundant basal resources, fishes and invertebrates, which were collected in April and October 2012. Individuals of the three focal species (n = 138: C. lugubris, n = 56; E. nigricans, n = 18; M. pavonina, n = 64) were collected during four expeditions to SPSPA (April and October of 2011 and 2012). Results suggest that this shallow water food web is supported by trophic pathways originating from benthic resources. Stable isotope data suggest potential competitive interactions between the whitespot moray and the other two mesopredators. Conversely, stomach content data suggest little niche overlap in the three focal species, but these data must be interpreted carefully because of the small sample sizes and restricted temporal sampling windows. All three mesopredators have a significant, albeit weak, relationship between body size and δ15N, suggesting ontogenetic diet shifts. These data contribute baseline information to assess shifts in food web structure that may stem from top predator decline in this unique ecosystem.}, number={1}, journal={JOURNAL OF APPLIED ICHTHYOLOGY}, author={Pinheiro, E. and Layman, C. A. and Castello, J. P. and Leite, T. S.}, year={2017}, month={Feb}, pages={47–53} } @article{yeager_stoner_peters_layman_2016, title={A terrestrial-aquatic food web subsidy is potentially mediated by multiple predator effects on an arboreal crab}, volume={475}, ISSN={["1879-1697"]}, DOI={10.1016/j.jembe.2015.10.017}, abstractNote={Terrestrial-aquatic food web subsidies are known to affect food web structure, ecosystem productivity, and stability of recipient habitats. This study describes a prey flux across the land–water interface associated with a behavioral response to multiple predators. Specifically, mangrove tree crabs (Aratus pisonii, hereafter Aratus) are primarily arboreal, but may jump off mangrove trees to escape avian predators, making them vulnerable to fish predation. Mesocosm experiments, field observations, and tethering assays were used to investigate behavioral responses, habitat shifts, and risk for Aratus associated with these two predator types. In the field, Aratus spent most of their time above the water on mangroves, where risk is lowest. In response to simulated bird strikes in mesocosm trials, crabs jumped off trees to escape imminent risk, and spent more time in and near the water, enhancing risk of fish predation. Fish attacks on crabs were nearly three times greater in treatments with simulated bird attacks. In addition, empirical diet data was used to examine the importance of Aratus as a prey item for a fish predator. Aratus represented up to 29% of diet by volume for one of the most common mesopredators in the Caribbean (gray snapper Lutjanus griseus), with the proportion varying greatly across space. Because Aratus consume mangrove-derived carbon, their consumption by aquatic predators represents another pathway by which mangrove production may be incorporated into aquatic food webs. These data suggest how the nexus of behavioral and food web ecology may provide for new perspectives on energy flow between ecosystems.}, journal={JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY}, author={Yeager, Lauren A. and Stoner, Elizabeth W. and Peters, Joseph R. and Layman, Craig A.}, year={2016}, month={Feb}, pages={73–79} } @article{stoner_sebilian_layman_2016, title={Comparison of zooxanthellae densities from upside-down jellyfish, Cassiopea xamachana, across coastal habitats of The Bahamas}, volume={51}, ISSN={["0718-1957"]}, DOI={10.4067/s0718-19572016000100022}, abstractNote={Anthropogenic disturbances may drive jellyfish blooms, and previous studies have suggested this is the case for upside-down jellyfish (Cassiopea xamachana). Cassiopea were found to have higher mean zooxanthellae densities in human-impacted areas on Abaco Island, The Bahamas, suggesting that nutrient loading in impacted sites may be one factor driving zooxanthellate jellyfish blooms. Gut contents from Cassiopea medusae were positively correlated to zooxanthellae densities, indicating that heterotrophically-derived nutrition may be an important factor in facilitating increased zooxanthellae population densities. Understanding the mechanisms driving jellyfish blooms is crucial for developing effective management strategies in impacted coastal ecosystems.}, number={1}, journal={REVISTA DE BIOLOGIA MARINA Y OCEANOGRAFIA}, author={Stoner, Elizabeth W. and Sebilian, Serina S. and Layman, Craig A.}, year={2016}, month={Apr}, pages={203–208} } @article{allgeier_valdivia_cox_layman_2016, title={Fishing down nutrients on coral reefs}, volume={7}, ISSN={["2041-1723"]}, DOI={10.1038/ncomms12461}, abstractNote={Abstract}, journal={NATURE COMMUNICATIONS}, author={Allgeier, Jacob E. and Valdivia, Abel and Cox, Courtney and Layman, Craig A.}, year={2016}, month={Aug} } @article{layman_allgeier_montana_2016, title={Mechanistic evidence of enhanced production on artificial reefs: A case study in a Bahamian seagrass ecosystem}, volume={95}, ISSN={["1872-6992"]}, DOI={10.1016/j.ecoleng.2016.06.109}, abstractNote={The attraction-production question, i.e., do artificial reefs support new fish biomass or instead primarily attract fishes from other areas, is one of the most nuanced in coastal marine conservation. Here we provide a novel perspective on this issue, specifically regarding the nutrient dynamics of biogeochemical hotspots that develop following artificial reef construction. Fishes can translocate nutrients (i.e., nitrogen and phosphorus) from the surrounding seascape and concentrate them around artificial reefs, often increasing localized primary production. We discuss an example of this in a seagrass ecosystem, using a case study demonstrating the specific mechanism by which aboveground primary production is enhanced. Namely, when nutrient supply exceeds an ecological threshold, non-linear shifts in nutrient allocation occurs to aboveground tissues, serving to increase localized primary production. Identifying such ecological thresholds in resource allocation provides a powerful predictive tool in the context of fishery management. We suggest that such an ecosystem-level perspective should become more prominent in discussions regarding the attraction-production question of artificial reefs.}, journal={ECOLOGICAL ENGINEERING}, author={Layman, Craig A. and Allgeier, Jacob E. and Montana, Carmen G.}, year={2016}, month={Oct}, pages={574–579} } @article{anton_cure_layman_puntila_simpson_bruno_2016, title={Prey naivete to invasive lionfish Pterois volitans on Caribbean coral reefs}, volume={544}, ISSN={["1616-1599"]}, DOI={10.3354/meps11553}, abstractNote={Native prey can be particularly vulnerable to consumption by exotic predators. Prey naivete, the failure to recognize a novel predator due to lack of recent co-evolutionary history, likely facilitates the disproportionate impact that some exotic predators exert on prey populations. Lionfish Pterois volitans, exotic predators from the Pacific, have invaded coral reefs and other coastal habitats along the western Atlantic. Prey naivete towards novel lionfish was tested in field experiments and with observations using closest approach distance as the anti-predator response. We quantified the distance of prey fishes to exotic lionfish in both the Atlantic and Pacific (invasive and native ranges of lionfish) as well as to native predators in the Atlantic. In the Atlantic, exper- iments indicated that Haemulon plumierii, prey of lionfish, generally display a closer approach distance to exotic than to native predators, and field observations of free-ranging fish revealed that at least 5 other species of small fishes (Halichoeres bivitattus, Halichoeres garnoti, Scarus tae- niopterus, Stegastes leucostictus and Thalassoma bifasciatum) also might exhibit limited predator- avoidance behaviour towards invasive lionfish. We also found that 3 families of small fish (Labri- dae, Pomacentridae and Scaridae) maintained greater distances from lionfish in the Pacific compared with the Atlantic in both experimental and field observations. These results suggest prey naivete to exotic lionfish by at least 8 species of fish (Abudefduf saxatilis, H. plumierii, H. bivitattus, H. garnoti, S. taeniopterus, Sparisoma aurofrenatum, S. leucostictus and T. bifasciatum) in the Atlantic, which could be contributing to the rapid expansion of this invasive species by enhancing its fitness and reproductive output through high predation efficiency.}, journal={MARINE ECOLOGY PROGRESS SERIES}, author={Anton, Andrea and Cure, Katherine and Layman, Craig A. and Puntila, Riikka and Simpson, Michael S. and Bruno, John F.}, year={2016}, month={Feb}, pages={257–269} } @misc{layman_2016, title={The Biology of Mangroves and Seagrasses. Third Edition. The Biology of Habitats Series. By Peter J. Hogarth. Oxford and New York: Oxford University Press. $125.00 (hardcover); $59.95 (paper). x + 289 p.; ill.; index. ISBN: 978-0-19-871654-9 (hc); 978-0-19-871655-6 (pb). 2015.}, volume={91}, ISSN={0033-5770 1539-7718}, url={http://dx.doi.org/10.1086/686837}, DOI={10.1086/686837}, abstractNote={Previous articleNext article No AccessConservation BiologyThe Biology of Mangroves and Seagrasses. Third Edition. The Biology of Habitats Series. By Peter J. Hogarth. Oxford and New York: Oxford University Press. $125.00 (hardcover); $59.95 (paper). x + 289 p.; ill.; index. ISBN: 978-0-19-871654-9 (hc); 978-0-19-871655-6 (pb). 2015.Craig LaymanCraig LaymanApplied Ecology, North Carolina State University, Raleigh, North Carolina Search for more articles by this author Applied Ecology, North Carolina State University, Raleigh, North CarolinaPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Quarterly Review of Biology Volume 91, Number 2June 2016 Published in association with Stony Brook University Article DOIhttps://doi.org/10.1086/686837 Views: 85Total views on this site For permission to reuse, please contact [email protected]PDF download Crossref reports no articles citing this article.}, number={2}, journal={The Quarterly Review of Biology}, publisher={University of Chicago Press}, author={Layman, Craig}, year={2016}, month={Jun}, pages={215–215} } @article{albo-puigserver_navarro_coll_layman_palomera_2016, title={Trophic structure of pelagic species in the northwestern Mediterranean Sea}, volume={117}, ISSN={["1873-1414"]}, DOI={10.1016/j.seares.2016.09.003}, abstractNote={Ecological knowledge of food web interactions within pelagic marine communities is often limited, impairing our capabilities to manage these ecologically and economically important marine fish species. Here we used stable isotope analyses to investigate trophic interactions in the pelagic ecosystem of the northwestern Mediterranean Sea during 2012 and 2013. Our results suggest that European sardine, Sardina pilchardus, and anchovy, Engraulis encrasicolus, are consumers located at relatively low levels of the pelagic food web. Unexpectedly, the round sardinella, Sardinella aurita, appeared to be located at a higher trophic level than the other small pelagic fish species, although previous studies found similarity in their diets. Isotope data suggested that trophic niches of species within the genera Trachurus spp. and Scomber spp., were distinct. Atlantic bonito Sarda sarda, European hake Merluccius merluccius and European squid Loligo vulgaris, appeared to feed at higher trophic levels than other species. Despite some intraspecific seasonal variability for some species, community trophic structure appeared relatively stable through the year. These data provide an important step for developing models of food web dynamics in the northwestern Mediterranean Sea.}, journal={JOURNAL OF SEA RESEARCH}, author={Albo-Puigserver, Marta and Navarro, Joan and Coll, Marta and Layman, Craig A. and Palomera, Isabel}, year={2016}, month={Nov}, pages={27–35} } @article{archer_stoner_layman_2015, title={A complex interaction between a sponge (Halichondria melanadocia) and a seagrass (Thalassia testudinum) in a subtropical coastal ecosystem}, volume={465}, ISSN={["1879-1697"]}, DOI={10.1016/j.jembe.2015.01.003}, abstractNote={Foundation species, such as oysters, corals, and seagrasses, form the basis for entire ecosystems and are characterized by positive interactions with community members. However, many species interactions are context dependent, where the outcome or strength of the interaction depends on the biotic or abiotic conditions. Therefore, a mechanistic knowledge of species interactions, especially those involving foundation species, may allow for a more complete understanding of how anthropogenic changes influence nearshore ecosystems. This study describes the interaction between the seagrass Thalassia testudinum and the sponge Halichondria melanadocia, a species that grows around the base of seagrass shoots. A combination of surveys and experimental manipulations on Abaco Island, The Bahamas, revealed that the interaction between T. testudinum and H. melanadocia is a commensal relationship with the sponge benefiting from the presence of T. testudinum up to medium shoot densities (589–615 shoots per m2). The net neutral effect of H. melanadocia on T. testudinum is likely a balance of the negative effect of the sponge shading the seagrass with the positive effect of nitrogen and phosphorus supplied by the sponge. The mechanisms underlying the interaction between H. melanadocia and T. testudinum suggest that the interaction is likely context dependent. As such, environmental change, namely eutrophication, has the potential to shift the nature of this interaction from commensal to parasitic. A simple simulation showed that if this relationship becomes parasitic, above ground production in seagrass beds could be reduced. This study highlights the importance of a mechanistic understanding of species interactions involving foundation species when predicting human impact on the environment.}, journal={JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY}, author={Archer, Stephanie K. and Stoner, Elizabeth W. and Layman, Craig A.}, year={2015}, month={Apr}, pages={33–40} } @article{layman_giery_buhler_rossi_penland_henson_bogdanoff_cove_irizarry_schalk_et al._2015, title={A primer on the history of food web ecology: Fundamental contributions of fourteen researchers}, volume={4}, ISSN={2352-2496}, url={http://dx.doi.org/10.1016/J.FOOWEB.2015.07.001}, DOI={10.1016/J.FOOWEB.2015.07.001}, abstractNote={Food webs are one of the primary frameworks on which the ecological sciences have been built. Research in this field has burgeoned over recent decades, expanding into diverse sub-disciplines and employing many different methodological approaches. Here we structure a historical review around 14 researchers and the specific contributions they have made to the field. Beginning with Charles Elton's insights into food web structure, and continuing to contemporary ecologists and emerging areas of study, we highlight some of the most important empirical and theoretical advances made over the last century. The review highlights that there are fundamentally different ways in which food webs are depicted and studied. Specifically, when one views systems through mathematical, energy flow or functional lenses, very different perspectives on food web structure and dynamics emerge. The contributions of these scientists illustrate the considerable advances that the field has undergone, and they provide the foundation for expansive on-going research programs that fall under the broad umbrella of food web ecology.}, journal={Food Webs}, publisher={Elsevier BV}, author={Layman, Craig A. and Giery, Sean T. and Buhler, Stephanie and Rossi, Ryann and Penland, Tiffany and Henson, Mary N. and Bogdanoff, Alex K. and Cove, Michael V. and Irizarry, Amarilys D. and Schalk, Christopher M. and et al.}, year={2015}, month={Sep}, pages={14–24} } @article{giery_layman_langerhans_2015, title={Anthropogenic ecosystem fragmentation drives shared and unique patterns of sexual signal divergence among three species of Bahamian mosquitofish}, volume={8}, ISSN={["1752-4571"]}, DOI={10.1111/eva.12275}, abstractNote={Abstract}, number={7}, journal={EVOLUTIONARY APPLICATIONS}, author={Giery, Sean T. and Layman, Craig A. and Langerhans, R. Brian}, year={2015}, month={Aug}, pages={679–691} } @article{allgeier_layman_mumby_rosemond_2015, title={Biogeochemical implications of biodiversity and community structure across multiple coastal ecosystems}, volume={85}, ISSN={["1557-7015"]}, DOI={10.1890/14-0331.1}, abstractNote={Small‐scale experiments and theory suggest that ecological functions provided by communities become more stable with increased species richness. Whether these patterns manifest at regional spatial scales and within species‐rich communities (e.g., coral reefs) is largely unknown. We quantified five biogeochemical processes, and an aggregate measure of multifunctionality, in species‐rich coastal fish communities to test three questions: (1) Do previously predicted biodiversity–ecosystem‐function relationships hold across large spatial scales and in highly diverse communities? (2) Can additional covariates of community structure improve these relationships? (3) What is the role of community biomass and functional group diversity in maintaining biogeochemical processes under various scenarios of species loss across ecosystem types? These questions were tested across a large regional gradient of coral reef, mangrove and seagrass ecosystems. Statistical models demonstrated that species richness and the mean maximum body size per species strongly predicted biogeochemical processes in all ecosystem types, but functional group diversity was only a weak predictor. Simulating three scenarios of species loss demonstrated that conserving community biomass alone increased the ability for communities to maintain ecosystem processes. Multifunctionality of biogeochemical processes was maintained least in simulations that conserved biomass and community structure, underscoring the relative lack of importance of community structure in maintaining multiple simultaneous ecosystem functions in this system. Findings suggest that conserving community biomass alone may be sufficient to sustain certain biogeochemical processes, but when considering conservation of multiple simultaneous biogeochemical processes, management efforts should focus first on species richness.}, number={1}, journal={ECOLOGICAL MONOGRAPHS}, author={Allgeier, Jacob E. and Layman, Craig A. and Mumby, Peter J. and Rosemond, Amy D.}, year={2015}, month={Feb}, pages={117–132} } @article{stoner_layman_2015, title={Bristle worms attack: benthic jellyfish are not trophic dead ends}, volume={13}, ISSN={["1540-9309"]}, DOI={10.1890/1540-9295-13.4.226}, abstractNote={P (open-ocean) jellyfish have often been considered trophic “dead ends” (Hansson and Norrman 1995; Lynam et al. 2006). However, various studies have indicated that some terrestrial and aquatic species do frequently consume jellyfish, despite their low nutritional quality (Doyle et al. 2007, 2014). Much less is known about the role of benthic (bottom-dwelling) jellyfish in marine and estuarine food webs, a topic that is increasingly relevant as human disturbances can stimulate benthic jellyfish blooms (Stoner et al. 2011, 2014). Such blooms could potentially be controlled by top-down predation pressure, but little information is available on the possible predators of these animals. So it was with great interest that we recently observed and recorded a benthic jellyfish, Cassiopea spp (hereafter Cassiopea), being preyed upon by bristle worms (Hermodice carunculata). Cassiopea are semi-sessile, benthic jellyfish found all over the world in a range of coastal habitat types, including seagrass beds, coral reefs, mangrove forests, and canals. They are commonly referred to as “upside-down jellyfish”, because as medusae (the free-swimming adult life stage of jellyfish) they rest on the substrate with their oral arms extending upward. Cassiopea use this orientation to acquire light, because, like certain corals, their tissues contain photosynthetic algae that provide them with carbohydrates. When disturbed, Cassiopea release mucus filled with nematocysts (stinging cells), presumably as a defense against predators. Where abundant, these jellyfish have been found to alter the structure and function of nearshore ecosystems (Stoner et al. 2014). For instance, they were shown to reduce seagrass shoot densities in a turtle grass (Thalassia testudinum) bed in The Bahamas, leading to a decline in the densities of other benthic fauna (Stoner et al. 2014). To date, the only documented predator of Cassiopea is a nudibranch – Dondice parguerensis – that occurs around Puerto Rico; this animal consumes only the oral arms, which can subsequently regenerate (Brandon and Cutress 1985). Our observations were made in a tidal creek on Abaco Island, part of the Bahamian Archipelago in the western North Atlantic Ocean. The dominant emergent vegetation in the area is red mangrove (Rhizophora mangle), with a heterogeneous substrate of seagrass (primarily T testudinum), hard bottom, and sand flats. Cassiopea are predominantly found in seagrass beds but often float into hard bottom areas on strong tidal currents. In April 2014, we documented the bristle worm H carunculata, an amphinomid polychaete, consuming a Cassiopea jellyfish. H carunculata, commonly called the bearded fireworm due to its venomous setae (bristles), is a well-known predator of anemones and coral polyps in reef ecosystems (Lizama and Blanquet 1975; Witman 1988). After a jellyfish had settled on the sediment surface, the bristle worms began preying on it, everting their buccal mass, a muscular area on the head containing the pharynx and esophagus (Figure 1). On several occasions, we observed multiple worms feeding on a single jellyfish at the same time, wrapping their bodies either partially or completely around it (Figure 2). Notably, all of the worms we saw feeding on Cassiopea were fairly large (> 30 cm long), whereas H carunculata in shallow marine ecosystems around Abaco Island are typically just a few centimeters long. In April and August of 2014, we used video cameras to record predation events. For each underwater trial, we selected one Cassiopea medusa from adjacent seagrass beds and placed it in front of the camera; we did not see any worms in the area when the trials were initiated. We ran trials on separate days during high tide in different parts of the creek. In one of these trials, we placed a dead fish (ballyhoo, Hemiramphus brasiliensis) next to the Cassiopea to test whether H carunculata would prefer an alternative, readily available prey item. We also conducted one nighttime feeding trial using infrared lighting with the video setup. In five of the six daytime trials, H carunculata moved toward the NATURAL HISTORY NOTES NATURAL HISTORY NOTES}, number={4}, journal={FRONTIERS IN ECOLOGY AND THE ENVIRONMENT}, author={Stoner, Elizabeth W. and Layman, Craig A.}, year={2015}, month={May}, pages={226–227} } @article{huijbers_nagelkerken_layman_2015, title={Fish movement from nursery bays to coral reefs: a matter of size?}, volume={750}, ISSN={["1573-5117"]}, DOI={10.1007/s10750-014-2162-4}, abstractNote={Movement of fish across habitat boundaries provides an important link between marine ecosystems such as mangroves, seagrass beds, and coral reefs, yet direct evidence of ontogenetic movements across these systems is scarce. We used acoustic telemetry to investigate movement patterns between bay nursery habitats and adult reef habitats by a common Caribbean fish (Lutjanus apodus). We hypothesized that juvenile fish residing in their nurseries increase their home range as they grow and eventually include coral reefs in their activity range before their permanent migration to this adult habitat. Tagged fish were detected by underwater receivers for a period up to 12 months and a clear diel pattern was visible with most detections occurring during nighttime. Bay-to-reef movements were undertaken by fish that were larger than fish that were only detected in the bay. Stable isotope values of fin tissue from fish that showed reef-ward movements were similar to those of fish remaining in the bay, indicating that these movements were likely exploratory behavior as opposed to repeated feeding excursions. Understanding cross-habitat ontogenetic movements is essential for identification of ecologically relevant spatial scales for management of coastal fish populations.}, number={1}, journal={HYDROBIOLOGIA}, author={Huijbers, Chantal M. and Nagelkerken, Ivan and Layman, Craig A.}, year={2015}, month={May}, pages={89–101} } @article{archer_allgeier_semmens_heppell_pattengill-semmens_rosemond_bush_mccoy_johnson_layman_2015, title={Hot moments in spawning aggregations: implications for ecosystem-scale nutrient cycling}, volume={34}, ISSN={["1432-0975"]}, DOI={10.1007/s00338-014-1208-4}, number={1}, journal={CORAL REEFS}, author={Archer, Stephanie K. and Allgeier, Jacob E. and Semmens, Brice X. and Heppell, Scott A. and Pattengill-Semmens, Christy V. and Rosemond, Amy D. and Bush, Phillippe G. and McCoy, Croy M. and Johnson, Bradley C. and Layman, Craig A.}, year={2015}, month={Mar}, pages={19–23} } @article{layman_newsome_crawford_2015, title={Individual-level niche specialization within populations: emerging areas of study}, volume={178}, ISSN={["1432-1939"]}, DOI={10.1007/s00442-014-3209-y}, number={1}, journal={OECOLOGIA}, author={Layman, Craig A. and Newsome, Seth D. and Crawford, Tara Gancos}, year={2015}, month={May}, pages={1–4} } @article{giery_layman_2015, title={Interpopulation Variation in a Condition-Dependent Signal: Predation Regime Affects Signal Intensity and Reliability}, volume={186}, ISSN={0003-0147 1537-5323}, url={http://dx.doi.org/10.1086/682068}, DOI={10.1086/682068}, abstractNote={In many models of sexual selection, conspicuous ornaments are preferred by mates because they indicate heritable signaler viability. To function as indicators, ornaments must exhibit a proportional relationship between expression and viability. In cases where the evolutionary interests of signaler and receiver diverge, selection favors exploitative exaggeration by low-viability individuals producing unreliable signals. Theory suggests that the evolutionary stability of such communication systems requires costs that prevent low-viability males from expressing disproportionately intense signals. Therefore, given ecological variation in signaling cost, the reliability of signaling systems will vary concomitantly. In this study, we assess the effect of a variable signal cost, predation, on signal intensity and reliability among 16 populations of Bahamas mosquitofish (Gambusia hubbsi) that use colorful dorsal fins in courtship displays. We found that fin coloration was more intense in low-predation sites and could be used to predict body condition. However, this predictive relationship was apparent only in populations subject to predation risk. We demonstrate an important role for ecological signaling cost in communication and show that ecological heterogeneity drives interpopulation variation in both the intensity and the reliability of a sexual signal.}, number={2}, journal={The American Naturalist}, publisher={University of Chicago Press}, author={Giery, Sean T. and Layman, Craig A.}, year={2015}, month={Aug}, pages={187–195} } @article{fodrie_yeager_grabowski_layman_sherwood_kenworthy_2015, title={Measuring individuality in habitat use across complex landscapes: approaches, constraints, and implications for assessing resource specialization}, volume={178}, ISSN={["1432-1939"]}, DOI={10.1007/s00442-014-3212-3}, abstractNote={Many mobile marine species are presumed to utilize a broad spectrum of habitats, but this seemingly generalist life history may arise from conspecifics specializing on distinct habitat alternatives to exploit foraging, resting/refuge, or reproductive opportunities. We acoustically tagged 34 red drum, and mapped sand, seagrass, marsh, or oyster (across discrete landscape contexts) use by each uniquely coded individual. Using 144,000 acoustic detections, we recorded differences in habitat use among red drum: proportional use of seagrass habitat ranged from 0 to 100%, and use of oyster-bottom types also varied among fish. WIC/TNW and IS metrics (previously applied vis-à-vis diet specialization) consistently indicated that a typical red drum overlapped >70% with population-level niche exploitation. Monte Carlo permutations showed these values were lower than expected had fish drawn from a common habitat-use distribution, but longitudinal comparisons did not provide evidence of temporally consistent individuality, suggesting that differences among individuals were plastic and not reflective of true specialization. Given the range of acoustic detections we captured (from tens to 1,000s per individual), which are substantially larger sample sizes than in many diet studies, we extended our findings by serially reducing or expanding our data in simulations to evaluate sample-size effects. We found that the results of null hypothesis testing for specialization were highly dependent on sample size, with thresholds in the relationship between sample size and associated P-values. These results highlight opportunities and potential caveats in exploring individuality in habitat use. More broadly, exploring individual specialization in fine-scale habitat use suggests that, for mobile marine species, movement behaviors over shorter (≤weeks), but not longer (≥months), timescales may serve as an underlying mechanism for other forms of resource specialization.}, number={1}, journal={OECOLOGIA}, author={Fodrie, F. Joel and Yeager, Lauren A. and Grabowski, Jonathan H. and Layman, Craig A. and Sherwood, Graham D. and Kenworthy, Matthew D.}, year={2015}, month={May}, pages={75–87} } @article{allgeier_wenger_rosemond_schindler_layman_2015, title={Metabolic theory and taxonomic identity predict nutrient recycling in a diverse food web}, volume={112}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.1420819112}, abstractNote={Significance}, number={20}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Allgeier, Jacob Edward and Wenger, Seth J. and Rosemond, Amy D. and Schindler, Daniel E. and Layman, Craig A.}, year={2015}, month={May}, pages={E2640–E2647} } @article{riesch_easter_layman_langerhans_2015, title={Rapid human-induced divergence of life-history strategies in Bahamian livebearing fishes (family Poeciliidae)}, volume={84}, ISSN={["1365-2656"]}, DOI={10.1111/1365-2656.12425}, abstractNote={Summary}, number={6}, journal={JOURNAL OF ANIMAL ECOLOGY}, author={Riesch, Ruediger and Easter, Tara and Layman, Craig A. and Langerhans, Randall Brian}, year={2015}, month={Nov}, pages={1732–1743} } @misc{nifong_layman_silliman_2015, title={Size, sex and individual-level behaviour drive intrapopulation variation in cross-ecosystem foraging of a top-predator}, volume={84}, ISSN={["1365-2656"]}, DOI={10.1111/1365-2656.12306}, abstractNote={Summary}, number={1}, journal={JOURNAL OF ANIMAL ECOLOGY}, author={Nifong, James C. and Layman, Craig A. and Silliman, Brian R.}, year={2015}, month={Jan}, pages={35–48} } @article{montana_layman_winemiller_2015, title={Species-area relationship within benthic habitat patches of a tropical floodplain river: An experimental test}, volume={40}, ISSN={["1442-9993"]}, DOI={10.1111/aec.12218}, abstractNote={Abstract}, number={3}, journal={AUSTRAL ECOLOGY}, author={Montana, Carmen G. and Layman, Craig A. and Winemiller, Kirk O.}, year={2015}, month={May}, pages={331–336} } @article{jud_nichols_layman_2014, title={Broad salinity tolerance in the invasive lionfish Pterois spp. may facilitate estuarine colonization}, volume={98}, ISSN={0378-1909 1573-5133}, url={http://dx.doi.org/10.1007/S10641-014-0242-Y}, DOI={10.1007/S10641-014-0242-Y}, number={1}, journal={Environmental Biology of Fishes}, publisher={Springer Science and Business Media LLC}, author={Jud, Zachary R. and Nichols, Patrick K. and Layman, Craig A.}, year={2014}, month={Feb}, pages={135–143} } @article{yeager_layman_hammerschlag-peyer_2014, title={Diet variation of a generalist fish predator, grey snapper Lutjanus griseus, across an estuarine gradient: trade-offs of quantity for quality?}, volume={85}, ISSN={["1095-8649"]}, DOI={10.1111/jfb.12416}, abstractNote={This study examined diet, prey quality and growth for a generalist fish predator, grey snapper Lutjanus griseus, at five sites across an estuarine gradient in the Loxahatchee River estuary, Florida, U.S.A. Lutjanus griseus diets shifted from dominance by low quality, intertidal crabs upstream to an increased reliance on higher quality shrimp, fishes and benthic crabs downstream. Frequency of L. griseus with empty stomachs was higher at downstream sites. Lutjanus griseus growth rates did not vary among sites. Results indicate that L. griseus may be able to compensate for lower quality prey upstream by consuming more, and thus individuals are able to maintain similar levels of energy balance and growth rates across the estuarine gradient. Elucidating mechanisms, such as compensatory feeding, that enable generalist species to remain successful across habitat conditions are critical to understanding their organismal ecology and may facilitate predictions about the response of generalists to landscape alteration.}, number={2}, journal={JOURNAL OF FISH BIOLOGY}, author={Yeager, L. A. and Layman, C. A. and Hammerschlag-Peyer, C. M.}, year={2014}, month={Aug}, pages={264–277} } @article{chacin_giery_yeager_layman_brian langerhans_2014, title={Does hydrological fragmentation affect coastal bird communities? A study from Abaco Island, The Bahamas}, volume={23}, ISSN={0923-4861 1572-9834}, url={http://dx.doi.org/10.1007/S11273-014-9389-8}, DOI={10.1007/S11273-014-9389-8}, number={3}, journal={Wetlands Ecology and Management}, publisher={Springer Science and Business Media LLC}, author={Chacin, Dinorah H. and Giery, Sean T. and Yeager, Lauren A. and Layman, Craig A. and Brian Langerhans, R.}, year={2014}, month={Oct}, pages={551–557} } @article{yeager_stoner_zapata_layman_2014, title={Does landscape context mediate the nature of density dependence for a coral reef fish?}, volume={24}, ISSN={["1939-5582"]}, DOI={10.1890/13-2231.1}, abstractNote={Over‐harvest and landscape change are two of the greatest threats to marine ecosystems. Over‐harvest may directly affect key population regulation mechanisms (e.g., density dependence), with the magnitude of the effects being further influenced by changes in landscape structure and associated resource availability. Because resource availability and conspecific density often co‐vary within the natural landscape, manipulative experiments are needed to understand how changes in these two drivers may affect density dependence in wild populations. We used a common, shoaling, coral reef fish (white grunt, Haemulon plumierii) as our model species, and manipulated fish densities and landscape context of artificial reef habitats to assess the effects of each on fish condition. We found evidence of inverse density dependence, where individual condition was positively related to conspecific density; landscape context had little effect. Mean grunt condition on natural patch reefs was similar to that for our low grunt density treatment artificial reefs, possibly due to differences in fish densities or landscape context. These findings suggest that over‐harvest may have detrimental effects on wild populations that extend beyond mere reductions in population size, especially for group‐living species.}, number={7}, journal={ECOLOGICAL APPLICATIONS}, author={Yeager, Lauren A. and Stoner, Elizabeth W. and Zapata, Martha J. and Layman, Craig A.}, year={2014}, month={Oct}, pages={1833–1841} } @article{araújo_langerhans_giery_layman_2014, title={Ecosystem fragmentation drives increased diet variation in an endemic livebearing fish of the Bahamas}, volume={4}, ISSN={2045-7758}, url={http://dx.doi.org/10.1002/ECE3.1140}, DOI={10.1002/ECE3.1140}, abstractNote={Abstract}, number={16}, journal={Ecology and Evolution}, publisher={Wiley}, author={Araújo, Márcio S. and Langerhans, R. Brian and Giery, Sean T. and Layman, Craig A.}, year={2014}, month={Jul}, pages={3298–3308} } @article{layman_jud_nichols_2014, title={Lionfish alter benthic invertebrate assemblages in patch habitats of a subtropical estuary}, volume={161}, ISSN={0025-3162 1432-1793}, url={http://dx.doi.org/10.1007/S00227-014-2491-X}, DOI={10.1007/S00227-014-2491-X}, number={9}, journal={Marine Biology}, publisher={Springer Science and Business Media LLC}, author={Layman, C. A. and Jud, Z. R. and Nichols, P.}, year={2014}, month={Jul}, pages={2179–2182} } @article{stoner_yeager_sweatman_sebilian_layman_2014, title={Modification of a seagrass community by benthic jellyfish blooms and nutrient enrichment}, volume={461}, ISSN={0022-0981}, url={http://dx.doi.org/10.1016/J.JEMBE.2014.08.005}, DOI={10.1016/J.JEMBE.2014.08.005}, abstractNote={Anthropogenic activities are increasing the number and intensity of disturbances, often acting in concert, in ecosystems across the globe. One result of human activities in many marine ecosystems is an increased abundance of jellyfish (jellyfish blooms), which have garnered recent attention for their detrimental ecological and economic impacts. We conducted a field experiment to determine effects of proliferations of benthic jellyfish, Cassiopea spp., and another common disturbance, anthropogenic nutrient enrichment (via fertilizer additions), on a shallow seagrass community in Abaco, Bahamas. Results suggested a reduction in seagrass abundance and habitat complexity in both jellyfish and nutrient enrichment treatments. Jellyfish additions were associated with reduced faunal densities; nutrient enrichment drove shifts in faunal community composition. Grazing frequency was substantially higher in nutrient-enriched plots, and lower in plots with jellyfish alone or jellyfish combined with nutrients, suggesting that jellyfish may act as a deterrent to grazers. These findings highlight the inherent complexities in predicting ecological changes within shallow seagrass ecosystems.}, journal={Journal of Experimental Marine Biology and Ecology}, publisher={Elsevier BV}, author={Stoner, Elizabeth W. and Yeager, Lauren A. and Sweatman, Jennifer L. and Sebilian, Serina S. and Layman, Craig A.}, year={2014}, month={Dec}, pages={185–192} } @article{layman_jud_archer_riera_2014, title={Provision of ecosystem services by human-made structures in a highly impacted estuary}, volume={9}, ISSN={["1748-9326"]}, DOI={10.1088/1748-9326/9/4/044009}, abstractNote={Water filtration is one of the most important ecosystem services provided by sessile organisms in coastal ecosystems. As a consequence of increased coastal development, human-made shoreline structures (e.g., docks and bulkheads) are now common, providing extensive surface area for colonization by filter feeders. We estimate that in a highly urbanized sub-tropical estuary, water filtration capacity supported by filter feeding assemblages on dock pilings accounts for 11.7 million liters of water h−1, or ∼30% of the filtration provided by all natural oyster reef throughout the estuary. Assemblage composition, and thus filtration capacity, varied as a function of piling type, suggesting that the choice of building material has critical implications for ecosystem function. A more thorough depiction of the function of coastal ecosystems necessitates quantification of the extensive ecosystem services associated with human-made structures.}, number={4}, journal={ENVIRONMENTAL RESEARCH LETTERS}, author={Layman, Craig A. and Jud, Zachary R. and Archer, Stephanie K. and Riera, David}, year={2014}, month={Apr} } @article{cote_darling_malpica-cruz_smith_green_curtis-quick_layman_2014, title={What Doesn't Kill You Makes You Wary? Effect of Repeated Culling on the Behaviour of an Invasive Predator}, volume={9}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0094248}, abstractNote={As a result of being hunted, animals often alter their behaviour in ways that make future encounters with predators less likely. When hunting is carried out for conservation, for example to control invasive species, these behavioural changes can inadvertently impede the success of future efforts. We examined the effects of repeated culling by spearing on the behaviour of invasive predatory lionfish (Pterois volitans/miles) on Bahamian coral reef patches. We compared the extent of concealment and activity levels of lionfish at dawn and midday on 16 coral reef patches off Eleuthera, The Bahamas. Eight of the patches had been subjected to regular daytime removals of lionfish by spearing for two years. We also estimated the distance at which lionfish became alert to slowly approaching divers on culled and unculled reef patches. Lionfish on culled reefs were less active and hid deeper within the reef during the day than lionfish on patches where no culling had occurred. There were no differences at dawn when removals do not take place. Lionfish on culled reefs also adopted an alert posture at a greater distance from divers than lionfish on unculled reefs. More crepuscular activity likely leads to greater encounter rates by lionfish with more native fish species because the abundance of reef fish outside of shelters typically peaks at dawn and dusk. Hiding deeper within the reef could also make remaining lionfish less likely to be encountered and more difficult to catch by spearfishers during culling efforts. Shifts in the behaviour of hunted invasive animals might be common and they have implications both for the impact of invasive species and for the design and success of invasive control programs.}, number={4}, journal={PLOS ONE}, author={Cote, Isabelle M. and Darling, Emily S. and Malpica-Cruz, Luis and Smith, Nicola S. and Green, Stephanie J. and Curtis-Quick, Jocelyn and Layman, Craig}, year={2014}, month={Apr} } @article{burkepile_allgeier_shantz_pritchard_lemoine_bhatti_layman_2013, title={Nutrient supply from fishes facilitates macroalgae and suppresses corals in a Caribbean coral reef ecosystem}, volume={3}, ISSN={2045-2322}, url={http://dx.doi.org/10.1038/SREP01493}, DOI={10.1038/SREP01493}, abstractNote={On coral reefs, fishes can facilitate coral growth via nutrient excretion; however, as coral abundance declines, these nutrients may help facilitate increases in macroalgae. By combining surveys of reef communities with bioenergetics modeling, we showed that fish excretion supplied 25 times more nitrogen to forereefs in the Florida Keys, USA, than all other biotic and abiotic sources combined. One apparent result was a positive relationship between fish excretion and macroalgal cover on these reefs. Herbivore biomass also showed a negative relationship with macroalgal cover, suggesting strong interactions of top-down and bottom-up forcing. Nutrient supply by fishes also showed a negative correlation with juvenile coral density, likely mediated by competition between macroalgae and corals, suggesting that fish excretion may hinder coral recovery following large-scale coral loss. Thus, the impact of nutrient supply by fishes may be context-dependent and reinforce either coral-dominant or coral-depauperate reef communities depending on initial community states.}, number={1}, journal={Scientific Reports}, publisher={Springer Science and Business Media LLC}, author={Burkepile, Deron E. and Allgeier, Jacob E. and Shantz, Andrew A. and Pritchard, Catharine E. and Lemoine, Nathan P. and Bhatti, Laura H. and Layman, Craig A.}, year={2013}, month={Mar} } @article{hammerschlag-peyer_allgeier_layman_2013, title={Predator effects on faunal community composition in shallow seagrass beds of The Bahamas}, volume={446}, ISSN={["0022-0981"]}, DOI={10.1016/j.jembe.2013.06.002}, abstractNote={Much emphasis has been placed on predator effects that cascade through food webs. Such top-down effects seem to be most common in systems with relatively simple food chains, and rarer in species-rich systems where numerous weak interactions among species can buffer strong top-down effects. Seagrass ecosystems are typically species-rich and characterized by complex food webs, but evidence of top-down effects in these systems has been mixed. We examined effects of predatory fishes on the species richness, biomass, density, and composition of the epifaunal community in a shallow seagrass ecosystem of The Bahamas. We used exclusion experiments at two different spatial scales, and applied mesh sizes that excluded different-sized predator individuals. We found some evidence of species-level top-down effects (i.e., strong interactions within a subset of the community), driving higher biomass in at least one decapod mesopredator. In contrast, community-level predator effects were rather weak, with predator size and spatial scale of experiments displaying no detectable impact on the overall epifaunal community. Multiple factors may have contributed to these patterns, including high species richness, relatively shallow water depth, small-scale spatial variation in habitat features, and the size and abundance of predators. Because of the rapid global decline of seagrasses and their associated fauna, increased knowledge of predator effects on faunal communities of seagrass beds is critical for long-term conservation efforts.}, journal={JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY}, author={Hammerschlag-Peyer, Caroline M. and Allgeier, Jacob E. and Layman, Craig A.}, year={2013}, month={Aug}, pages={282–290} } @article{jud_layman_2012, title={Site fidelity and movement patterns of invasive lionfish, Pterois spp., in a Florida estuary}, volume={414-415}, ISSN={0022-0981}, url={http://dx.doi.org/10.1016/j.jembe.2012.01.015}, DOI={10.1016/j.jembe.2012.01.015}, abstractNote={Understanding how individuals within a population of invasive organisms disperse during various life history stages has obvious implications for long term population dynamics in the invaded range. With the rapid expansion of the invasive Indo-Pacific lionfish (Pterois volitans and Pterois miles) in the western Atlantic and Caribbean, it has become increasingly important to understand how individuals move following initial recruitment, as this may have critical implications for population control and management. We conducted a 10-month mark–recapture study in the lower Loxahatchee River estuary (Florida, USA) to identify movement patterns and site fidelity in juvenile and young adult lionfish. We tagged 55 lionfish, ranging in size from 45 to 185 mm standard length (66–256 mm total length). Eighty percent of the tagged fish were recaptured at least one time during the course of the study. Lionfish in this system exhibited extremely high site fidelity over extended periods of time and across multiple size classes. Maximum range occupied by individuals along the shoreline of the estuary was small (mean = 28 m, asymmetrical 95% CI: 10 to 51 m), and did not vary with lionfish size. The majority of lionfish recaptures (74%) occurred at or near (0–10 m) the previous capture site, even after weeks or months at liberty. In systems where lionfish exhibit extremely high site fidelity and small maximum ranges, localized population control may be feasible, since lionfish removed from a given habitat would be replaced largely through larval recruitment rather than migration of older individuals. However, since lionfish grow extremely rapidly (averaging 0.46 mm/day, but reaching as high as 0.78 mm/day in one individual), localized control efforts would need to be carried out frequently in order to maintain a younger, smaller population. Localized control may be less effective if lionfish exhibit greater movement and lower site fidelity in other invaded systems.}, journal={Journal of Experimental Marine Biology and Ecology}, publisher={Elsevier BV}, author={Jud, Zachary R. and Layman, Craig A.}, year={2012}, month={Mar}, pages={69–74} } @article{stoner_layman_yeager_hassett_2011, title={Effects of anthropogenic disturbance on the abundance and size of epibenthic jellyfish Cassiopea spp.}, volume={62}, ISSN={0025-326X}, url={http://dx.doi.org/10.1016/j.marpolbul.2011.03.023}, DOI={10.1016/j.marpolbul.2011.03.023}, abstractNote={Jellyfish blooms in pelagic systems appear to be increasing on a global scale because of anthropogenic impacts, but much less is known about the link between human activities and epibenthic jellyfish abundance. The aim of this study was to investigate whether the epibenthic jellyfish, Cassiopea spp., were found in greater abundance, and attained larger sizes, in coastal habitats adjacent to high human population densities compared to sites adjacent to uninhabited areas on Abaco Island, Bahamas. Cassiopea spp. were found to be significantly more dense and larger in areas with high human population densities. Ambient nutrient levels and nutrient content of seagrass were elevated in high human population density sites, and may be one mechanism driving higher abundance and size of Cassiopea spp. Cassiopea spp. may have important effects on community structure and ecosystem function in critical coastal ecosystems (e.g., seagrass beds), and their impacts warrant further study.}, number={5}, journal={Marine Pollution Bulletin}, publisher={Elsevier BV}, author={Stoner, Elizabeth W. and Layman, Craig A. and Yeager, Lauren A. and Hassett, Heather M.}, year={2011}, month={May}, pages={1109–1114} } @article{yeager_layman_allgeier_2011, title={Effects of habitat heterogeneity at multiple spatial scales on fish community assembly}, volume={167}, ISSN={0029-8549 1432-1939}, url={http://dx.doi.org/10.1007/s00442-011-1959-3}, DOI={10.1007/s00442-011-1959-3}, abstractNote={Habitat variability at multiple spatial scales may affect community structure within a given habitat patch, even within seemingly homogenous landscapes. In this context, we tested the importance of habitat variables at two spatial scales (patch and landscape) in driving fish community assembly using experimental artificial reefs constructed across a gradient of seagrass cover in a coastal bay of The Bahamas. We found that species richness and benthic fish abundance increased over time, but eventually reached an asymptote. The correlation between habitat variables and community structure strengthened over time, suggesting deterministic processes were detectable in community assembly. Abundance of benthic fishes, as well as overall community structure, were predicted by both patch- and landscape-scale variables, with the cover of seagrass at the landscape-scale emerging as the most important explanatory variable. Results of this study indicate that landscape features can drive differences in community assembly even within a general habitat type (i.e., within seagrass beds). A primary implication of this finding is that human activities driving changes in seagrass cover may cause significant shifts in faunal community structure well before complete losses of seagrass habitat.}, number={1}, journal={Oecologia}, publisher={Springer Science and Business Media LLC}, author={Yeager, Lauren A. and Layman, Craig A. and Allgeier, Jacob E.}, year={2011}, month={Mar}, pages={157–168} } @article{yeager_layman_2011, title={Energy flow to two abundant consumers in a subtropical oyster reef food web}, volume={45}, ISSN={1386-2588 1573-5125}, url={http://dx.doi.org/10.1007/s10452-011-9352-1}, DOI={10.1007/s10452-011-9352-1}, number={2}, journal={Aquatic Ecology}, publisher={Springer Science and Business Media LLC}, author={Yeager, Lauren A. and Layman, Craig A.}, year={2011}, month={Feb}, pages={267–277} } @article{allgeier_rosemond_layman_2011, title={Variation in nutrient limitation and seagrass nutrient content in Bahamian tidal creek ecosystems}, volume={407}, ISSN={0022-0981}, url={http://dx.doi.org/10.1016/j.jembe.2011.07.005}, DOI={10.1016/j.jembe.2011.07.005}, abstractNote={The traditional model of nutrient availability in coastal estuarine ecosystems is based on predictable inputs of nitrogen (N) and phosphorus (P) via riverine and oceanic sources, respectively. But coastlines with low nutrient input from these sources may not fit into this simple framework. Here we use observational (seagrass nutrient content) and experimental (nutrient enrichment assays) data for assessing nutrient availability and limitation for primary producers along a spatial transect extending from the mouth (nearest to the ocean) to the terminal portion (boundary with the terrestrial ecosystem) of three coastal mangrove-lined tidal creeks in The Bahamas. Compiling seagrass nutrient content from all sites showed a negative relationship between seagrass nutrient limitation (either N or P) and distance from mouth, but this pattern differed across sites with respect to which nutrient was more limiting. Our experimental results demonstrated patterns of decreased response by microalgae to dual nutrient enrichment in one site with distance from the creek mouth, and increased response to single nutrient enrichment in another, with the third showing no trend along this gradient. Our findings show that Bahamian mangrove wetlands are extremely nutrient-limited ecosystems, and that the most limiting nutrient varied among sites. In general, these ecosystems deviate from the typical paradigm of spatial nutrient limitation patterns in estuaries. We suggest that various site-specific biological and physical factors may be more important than large-scale hydrologic factors in driving trends of nutrient availability in coastal ecosystems under strong nutrient constraints, such as in The Bahamas. Our findings suggest that even minor changes in nutrient loading rates can have significant implications for primary production in subtropical oligotrophic systems.}, number={2}, journal={Journal of Experimental Marine Biology and Ecology}, publisher={Elsevier BV}, author={Allgeier, Jacob E. and Rosemond, Amy D. and Layman, Craig A.}, year={2011}, month={Oct}, pages={330–336} } @article{jud_layman_shenker_2010, title={Diet of age-0 tarpon (Megalops atlanticus) in anthropogenically-modified and natural nursery habitats along the Indian River Lagoon, Florida}, volume={90}, ISSN={0378-1909 1573-5133}, url={http://dx.doi.org/10.1007/s10641-010-9734-6}, DOI={10.1007/s10641-010-9734-6}, number={3}, journal={Environmental Biology of Fishes}, publisher={Springer Science and Business Media LLC}, author={Jud, Zachary R. and Layman, Craig A. and Shenker, Jonathan M.}, year={2010}, month={Nov}, pages={223–233} } @article{grol_nagelkerken_rypel_layman_2010, title={Simple ecological trade-offs give rise to emergent cross-ecosystem distributions of a coral reef fish}, volume={165}, ISSN={0029-8549 1432-1939}, url={http://dx.doi.org/10.1007/s00442-010-1833-8}, DOI={10.1007/s00442-010-1833-8}, abstractNote={Ecosystems are intricately linked by the flow of organisms across their boundaries, and such connectivity can be essential to the structure and function of the linked ecosystems. For example, many coral reef fish populations are maintained by the movement of individuals from spatially segregated juvenile habitats (i.e., nurseries, such as mangroves and seagrass beds) to areas preferred by adults. It is presumed that nursery habitats provide for faster growth (higher food availability) and/or low predation risk for juveniles, but empirical data supporting this hypothesis is surprisingly lacking for coral reef fishes. Here, we investigate potential mechanisms (growth, predation risk, and reproductive investment) that give rise to the distribution patterns of a common Caribbean reef fish species, Haemulon flavolineatum (French grunt). Adults were primarily found on coral reefs, whereas juvenile fish only occurred in non-reef habitats. Contrary to our initial expectations, analysis of length-at-age revealed that growth rates were highest on coral reefs and not within nursery habitats. Survival rates in tethering trials were 0% for small juvenile fish transplanted to coral reefs and 24-47% in the nurseries. As fish grew, survival rates on coral reefs approached those in non-reef habitats (56 vs. 77-100%, respectively). As such, predation seems to be the primary factor driving across-ecosystem distributions of this fish, and thus the primary reason why mangrove and seagrass habitats function as nursery habitat. Identifying the mechanisms that lead to such distributions is critical to develop appropriate conservation initiatives, identify essential fish habitat, and predict impacts associated with environmental change.}, number={1}, journal={Oecologia}, publisher={Springer Science and Business Media LLC}, author={Grol, Monique G. G. and Nagelkerken, Ivan and Rypel, Andrew L. and Layman, Craig A.}, year={2010}, month={Nov}, pages={79–88} } @article{roach_winemiller_layman_zeug_2009, title={Consistent trophic patterns among fishes in lagoon and channel habitats of a tropical floodplain river: Evidence from stable isotopes}, volume={35}, ISSN={1146-609X}, url={http://dx.doi.org/10.1016/j.actao.2009.03.007}, DOI={10.1016/j.actao.2009.03.007}, abstractNote={The relationship between food web dynamics and hydrological connectivity in rivers should be strongly influenced by annual flood pulses that affect primary production dynamics and movement of organic matter and consumer taxa. We sampled basal production sources and fishes from connected lagoons and the main channel of a low-gradient, floodplain river within the Orinoco River Basin in Venezuela. Stable isotope analysis was used to model the contribution of four basal production sources to fishes, and to examine patterns of mean trophic position during the falling-water period of the annual flood cycle. IsoSource, a multi-source mixing model, indicated that proportional contributions from production sources to fish assemblages were similar in lagoons and the main channel. Although distributions differed, the means for trophic positions of fish assemblages as well as individual species were similar between the two habitats. These findings contradict recent food web studies conducted in temperate floodplain rivers that described significant differences in trophic positions of fishes from slackwater and floodplain versus main channel habitats. Low between-habitat trophic variation in this tropical river probably results from an extended annual flood pulse (ca. 5 mo.) that allows mixing of sestonic and allochthonous basal production sources and extensive lateral movements of fishes throughout the riverscape.}, number={4}, journal={Acta Oecologica}, publisher={Elsevier BV}, author={Roach, Katherine A. and Winemiller, Kirk O. and Layman, Craig A. and Zeug, Steven C.}, year={2009}, month={Jul}, pages={513–522} } @article{layman_montaña_allgeier_2009, title={Linking fish colonization rates and water level change in littoral habitats of a Venezuelan floodplain river}, volume={44}, ISSN={1386-2588 1573-5125}, url={http://dx.doi.org/10.1007/s10452-009-9256-5}, DOI={10.1007/s10452-009-9256-5}, number={1}, journal={Aquatic Ecology}, publisher={Springer Science and Business Media LLC}, author={Layman, Craig A. and Montaña, Carmen G. and Allgeier, Jacob E.}, year={2009}, month={Jun}, pages={269–273} } @article{adams_wolfe_layman_2009, title={Preliminary Examination of How Human-driven Freshwater Flow Alteration Affects Trophic Ecology of Juvenile Snook (Centropomus undecimalis) in Estuarine Creeks}, volume={32}, ISSN={1559-2723 1559-2731}, url={http://dx.doi.org/10.1007/s12237-009-9156-x}, DOI={10.1007/s12237-009-9156-x}, number={4}, journal={Estuaries and Coasts}, publisher={Springer Science and Business Media LLC}, author={Adams, Aaron J. and Wolfe, R. Kirby and Layman, Craig A.}, year={2009}, month={May}, pages={819–828} } @article{post_layman_arrington_takimoto_quattrochi_montaña_2007, title={Getting to the fat of the matter: models, methods and assumptions for dealing with lipids in stable isotope analyses}, volume={152}, ISSN={0029-8549 1432-1939}, url={http://dx.doi.org/10.1007/s00442-006-0630-x}, DOI={10.1007/s00442-006-0630-x}, abstractNote={Within an organism, lipids are depleted in (13)C relative to proteins and carbohydrates (more negative delta(13)C), and variation in lipid content among organisms or among tissue types has the potential to introduce considerable bias into stable isotope analyses that use delta(13)C. Despite the potential for introduced error, there is no consensus on the need to account for lipids in stable isotope analyses. Here we address two questions: (1) If and when is it important to account for the effects of variation in lipid content on delta(13)C? (2) If it is important, which method(s) are reliable and robust for dealing with lipid variation? We evaluated the reliability of direct chemical extraction, which physically removes lipids from samples, and mathematical normalization, which uses the carbon-to-nitrogen (C:N) ratio of a sample to normalize delta(13)C after analysis by measuring the lipid content, the C:N ratio, and the effect of lipid content on delta(13)C (Deltadelta(13)C) of plants and animals with a wide range of lipid contents. For animals, we found strong relationships between C:N and lipid content, between lipid content and Deltadelta(13)C, and between C:N and Deltadelta(13)C. For plants, C:N was not a good predictor of lipid content or Deltadelta(13)C, but we found a strong relationship between carbon content and lipid content, lipid content and Deltadelta(13)C, and between and carbon content and Deltadelta(13)C. Our results indicate that lipid extraction or normalization is most important when lipid content is variable among consumers of interest or between consumers and end members, and when differences in delta(13)C between end members is <10-12 per thousand. The vast majority of studies using natural variation in delta(13)C fall within these criteria. Both direct lipid extraction and mathematical normalization reduce biases in delta(13)C, but mathematical normalization simplifies sample preparation and better preserves the integrity of samples for delta(15)N analysis.}, number={1}, journal={Oecologia}, publisher={Springer Science and Business Media LLC}, author={Post, David M. and Layman, Craig A. and Arrington, D. Albrey and Takimoto, Gaku and Quattrochi, John and Montaña, Carman G.}, year={2007}, month={Jan}, pages={179–189} } @article{haney_silliman_fry_layman_rand_2007, title={The Pleistocene history of the sheepshead minnow (Cyprinodon variegatus): Non-equilibrium evolutionary dynamics within a diversifying species complex}, volume={43}, ISSN={1055-7903}, url={http://dx.doi.org/10.1016/j.ympev.2006.08.022}, DOI={10.1016/j.ympev.2006.08.022}, abstractNote={The sheepshead minnow, Cyprinodon variegatus, is a widespread fish species that typically inhabits coastal tidal marsh and mangrove swamp environments, ranging from Cape Cod, Massaschusetts to northern Mexico and into the Caribbean. This wide range crosses several biogeographic boundaries which are coincident with genetic structuring within numerous species originating in the Pleistocene. In addition, the more northerly reaches of this species range have been further subject to the evolutionary consequences of Pleistocene glaciation due to local extinction and recolonization of formerly glaciated sites. C. variegatus thus provides an excellent vertebrate model system within which to test the extent of genetic differentiation among populations in a dominant coastal ecosystem and examine patterns of historical demography in populations distributed along a latitudinal gradient. Using mitochondrial control region and ND2 sequence data, we discovered monophyletic clades within C. variegatus with divergence times within the Pleistocene, and very low gene flow between most sites. Intraspecific genetic breaks appear to correspond broadly to biogeographic or oceanic boundaries. Pleistocene climate change appears to have had dramatic impacts on the size and distribution of populations within and near the glacial margins, but has also affected populations far from formerly glaciated regions.}, number={3}, journal={Molecular Phylogenetics and Evolution}, publisher={Elsevier BV}, author={Haney, Robert A. and Silliman, Brian R. and Fry, Adam J. and Layman, Craig A. and Rand, David M.}, year={2007}, month={Jun}, pages={743–754} } @article{rypel_layman_arrington_2007, title={Water depth modifies relative predation risk for a motile fish taxon in Bahamian tidal creeks}, volume={30}, ISSN={1559-2723 1559-2731}, url={http://dx.doi.org/10.1007/bf03036517}, DOI={10.1007/bf03036517}, number={3}, journal={Estuaries and Coasts}, publisher={Springer Science and Business Media LLC}, author={Rypel, Andrew L. and Layman, Craig A. and Arrington, D. Albrey}, year={2007}, month={Jun}, pages={518–525} } @article{arrington_winemiller_layman_2005, title={Community assembly at the patch scale in a species rich tropical river}, volume={144}, ISSN={0029-8549 1432-1939}, url={http://dx.doi.org/10.1007/s00442-005-0014-7}, DOI={10.1007/s00442-005-0014-7}, abstractNote={In tropical floodplain rivers, communities associated with structurally complex habitats are disassembled and reassembled as aquatic organisms repeatedly colonize new areas in response to gradual but continuous changes in water level. Thus, a neutral model reflecting random colonization and extinction dynamics may be sufficient to predict assemblage patterns at the scale of local habitat patches. If water level fluctuations and associated patch dynamics are sufficiently predictable, however, community assembly on habitat patches also may be influenced by species-specific responses to habitat features and/or species interactions. We experimentally manipulated structural complexity and proximity to source habitat (which influences colonization rate) of simulated rocky patches in the littoral zone of a tropical lowland river and demonstrate significant effects of both factors on species density of fishes and macroinvertebrates. Interspecific variation in vagility significantly affected assemblage response to habitat complexity. In a second experiment, created habitat patches were sampled over time intervals ranging from 1 day to 36 days to examine temporal dynamics of community assembly. A null-model test revealed that assemblage structure became increasingly non-random, concomitant with increasing species density, over time. Community dynamics in newly formed habitat patches appeared to be dominated by dispersal, whereas in older patches, abundances of individual species increasingly were influenced by habitat characteristics. These data suggest that species-specific responses to environmental variation resulted, in part, because of species interactions. We conclude that community assembly in shallow habitats of this tropical lowland river is influenced by physical habitat characteristics, the spatial distribution of habitat patches, and species interactions as habitats are saturated with individuals.}, number={1}, journal={Oecologia}, publisher={Springer Science and Business Media LLC}, author={Arrington, D. Albrey and Winemiller, Kirk O. and Layman, Craig A.}, year={2005}, month={Mar}, pages={157–167} } @article{langerhans_layman_dewitt_2005, title={Male genital size reflects a tradeoff between attracting mates and avoiding predators in two live-bearing fish species}, volume={102}, ISSN={0027-8424 1091-6490}, url={http://dx.doi.org/10.1073/pnas.0500935102}, DOI={10.1073/pnas.0500935102}, abstractNote={ Male genitalia may experience more rapid, divergent evolution than any other animal character, but why? Research during the past several decades has culminated in the view that genital diversification primarily results from postmating sexual selection (e.g., sperm competition or cryptic female choice). However, the potential roles of premating sexual selection (e.g., mate choice) and natural selection have received little attention. We examined the possible importance of these mechanisms by investigating divergence in male genitalia among populations differing in predator regime for two species of live-bearing fish ( Gambusia affinis in Texas and Gambusia hubbsi in The Bahamas). When controlled for body size, males exhibited a larger gonopodium (sperm-transfer organ) in predator-free environments than in predatory environments, a trend that persisted across space (multiple populations), time (multiple years), and species. By conducting laboratory experiments with G. affinis , we found that premating sexual selection seems to favor larger male genitalia (females exhibited mating preference for males having larger gonopodia), but natural selection in the presence of predatory fishes seems to favor reduced genital size (larger gonopodium size was associated with reduced burst-swimming performance, an important antipredator behavior). Although postmating sexual selection is widely presumed to be the most important mechanism driving genital diversification, these findings suggest that alternative mechanisms, particularly for organisms that cannot retract their genitalia, may also prove important. }, number={21}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Langerhans, R. B. and Layman, C. A. and DeWitt, T. J.}, year={2005}, month={May}, pages={7618–7623} } @article{silliman_layman_geyer_zieman_2004, title={Predation by the black-clawed mud crab,Panopeus herbstii, in Mid-Atlantic salt marshes: Further evidence for top-down control of marsh grass production}, volume={27}, ISSN={0160-8347}, url={http://dx.doi.org/10.1007/bf02803375}, DOI={10.1007/bf02803375}, number={2}, journal={Estuaries}, publisher={Springer Science and Business Media LLC}, author={Silliman, Brian Reed and Layman, Craig A. and Geyer, Kane and Zieman, J. C.}, year={2004}, month={Apr}, pages={188–196} }