TY - JOUR TI - Arranging the bouquet of disease: floral traits and the transmission of plant and animal pathogens AU - McArt, Scott H. AU - Koch, Hauke AU - Irwin, Rebecca E. AU - Adler, Lynn S. T2 - Ecology Letters AB - Several floral microbes are known to be pathogenic to plants or floral visitors such as pollinators. Despite the ecological and economic importance of pathogens deposited in flowers, we often lack a basic understanding of how floral traits influence disease transmission. Here, we provide the first systematic review regarding how floral traits attract vectors (for plant pathogens) or hosts (for animal pathogens), mediate disease establishment and evolve under complex interactions with plant mutualists that can be vectors for microbial antagonists. Attraction of floral visitors is influenced by numerous phenological, morphological and chemical traits, and several plant pathogens manipulate floral traits to attract vectors. There is rapidly growing interest in how floral secondary compounds and antimicrobial enzymes influence disease establishment in plant hosts. Similarly, new research suggests that consumption of floral secondary compounds can reduce pathogen loads in animal pollinators. Given recent concerns about pollinator declines caused in part by pathogens, the role of floral traits in mediating pathogen transmission is a key area for further research. We conclude by discussing important implications of floral transmission of pathogens for agriculture, conservation and human health, suggesting promising avenues for future research in both basic and applied biology. DA - 2014/2/16/ PY - 2014/2/16/ DO - 10.1111/ele.12257 VL - 17 IS - 5 SP - 624-636 J2 - Ecology Letters LA - en OP - SN - 1461-023X 1461-0248 UR - http://dx.doi.org/10.1111/ele.12257 DB - Crossref ER - TY - JOUR TI - Effects of Suburbanization on Forest Bee Communities AU - Carper, Adrian L. AU - Adler, Lynn S. AU - Warren, Paige S. AU - Irwin, Rebecca E. T2 - Environmental Entomology AB - Urbanization is a dominant form of land-use change driving species distributions, abundances, and diversity. Previous research has documented the negative impacts of urbanization on the abundance and diversity of many groups of organisms. However, some organisms, such as bees, may benefit from moderate levels of development, depending on how development alters the availability of foraging and nesting resources. To determine how one type of low-intensity human development, suburbanization, affects bee abundance and diversity and the mechanisms involved, we surveyed bees across suburban and natural forests in the Raleigh-Durham area of North Carolina. We sampled for bees using a combination of bee bowls and hand-netting from March through July of 2008 and 2009. We found higher bee abundance in suburban than natural forests, and although observed species richness was greater in suburban than natural forests, there were no significant differences in rarefied richness or evenness estimates in either year. In addition, the effects of suburbanization were similar across bee species of varying ecological and life-history characteristics. At the local scale, bee abundance and species richness were both positively related to the abundance and richness of flowering species within forests, while the proportion of surrounding developed open areas, such as yards and roadsides, was a strong positive predictor of both bee abundance and richness at the landscape scale. These results suggest that open habitats and the availability of floral resources in suburban sites can support abundant and diverse bee communities and underscore the potential for native bee conservation in urban habitats. DA - 2014/4/1/ PY - 2014/4/1/ DO - 10.1603/en13078 VL - 43 IS - 2 SP - 253-262 J2 - Environ Entomol LA - en OP - SN - 0046-225X 1938-2936 UR - http://dx.doi.org/10.1603/en13078 DB - Crossref ER - TY - JOUR TI - Nectar Yeasts in the Tall Larkspur Delphinium barbeyi (Ranunculaceae) and Effects on Components of Pollinator Foraging Behavior AU - Schaeffer, Robert N. AU - Phillips, Cody R. AU - Duryea, M. Catherine AU - Andicoechea, Jonathan AU - Irwin, Rebecca E. T2 - PLoS ONE AB - Microorganisms frequently colonize the nectar of angiosperm species. Though capable of altering a suite of traits important for pollinator attraction, few studies exist that test the degree to which they mediate pollinator foraging behavior. The objective of our study was to fill this gap by assessing the abundance and diversity of yeasts associated with the perennial larkspur Delphinium barbeyi (Ranunculaceae) and testing whether their presence affected components of pollinator foraging behavior. Yeasts frequently colonized D. barbeyi nectar, populating 54-77% of flowers examined depending on site. Though common, the yeast community was species-poor, represented by a single species, Metschnikowia reukaufii. Female-phase flowers of D. barbeyi were more likely to have higher densities of yeasts in comparison to male-phase flowers. Pollinators were likely vectors of yeasts, as virgin (unvisited) flowers rarely contained yeasts compared to flowers open to pollinator visitation, which were frequently colonized. Finally, pollinators responded positively to the presence of yeasts. Bombus foragers both visited and probed more flowers inoculated with yeasts in comparison to uninoculated controls. Taken together, our results suggest that variation in the occurrence and density of nectar-inhabiting yeasts have the potential to alter components of pollinator foraging behavior linked to pollen transfer and plant fitness. DA - 2014/10/1/ PY - 2014/10/1/ DO - 10.1371/journal.pone.0108214 VL - 9 IS - 10 SP - e108214 J2 - PLoS ONE LA - en OP - SN - 1932-6203 UR - http://dx.doi.org/10.1371/journal.pone.0108214 DB - Crossref ER - TY - JOUR TI - Yeasts in nectar enhance male fitness in a montane perennial herb AU - Schaeffer, Robert N. AU - Irwin, Rebecca E. T2 - Ecology AB - Floral nectar of many plant species is prone to colonization by microbial organisms such as yeasts. Their presence and metabolism of nectar chemical components have the potential to modify a suite of floral traits important for pollinator attraction, including nectar quality and scent. However, studies on the direct and indirect effects of nectar‐inhabiting microorganisms on pollinator behavior and plant reproductive success remain rare. To determine their potential to affect pollinator behavior and plant fitness, we experimentally manipulated the common nectar‐inhabiting yeast Metschnikowia reukaufii in the nectar of Delphinium nuttallianum , a short‐lived montane perennial herb. We detected positive, indirect, pollinator‐mediated effects of yeasts on male plant fitness measured as pollen donation using powdered fluorescent dyes. However, we detected no direct or indirect effects on components of female fitness. Matching effects on male plant fitness, pollinators responded positively to the presence of yeasts, removing more nectar from flowers treated with M. reukaufii . Our results provide evidence of effects of nectar‐inhabiting yeasts on male plant fitness and highlight the importance of microorganisms in mediating plant–pollinator interactions and subsequent plant fitness. DA - 2014/7// PY - 2014/7// DO - 10.1890/13-1740.1 VL - 95 IS - 7 SP - 1792-1798 J2 - Ecology LA - en OP - SN - 0012-9658 1939-9170 UR - http://dx.doi.org/10.1890/13-1740.1 DB - Crossref ER - TY - JOUR TI - Does hydrological fragmentation affect coastal bird communities? A study from Abaco Island, The Bahamas AU - Chacin, Dinorah H. AU - Giery, Sean T. AU - Yeager, Lauren A. AU - Layman, Craig A. AU - Brian Langerhans, R. T2 - Wetlands Ecology and Management DA - 2014/10/1/ PY - 2014/10/1/ DO - 10.1007/S11273-014-9389-8 VL - 23 IS - 3 SP - 551-557 J2 - Wetlands Ecol Manage LA - en OP - SN - 0923-4861 1572-9834 UR - http://dx.doi.org/10.1007/S11273-014-9389-8 DB - Crossref KW - Anthropogenic change KW - The Bahamas KW - Habitat alteration KW - Mangroves KW - Wetland management KW - Wading birds ER - TY - JOUR TI - Broad salinity tolerance in the invasive lionfish Pterois spp. may facilitate estuarine colonization AU - Jud, Zachary R. AU - Nichols, Patrick K. AU - Layman, Craig A. T2 - Environmental Biology of Fishes DA - 2014/2/7/ PY - 2014/2/7/ DO - 10.1007/S10641-014-0242-Y VL - 98 IS - 1 SP - 135-143 J2 - Environ Biol Fish LA - en OP - SN - 0378-1909 1573-5133 UR - http://dx.doi.org/10.1007/S10641-014-0242-Y DB - Crossref KW - Estuary KW - Indian River Lagoon KW - Invasive marine fish KW - Lionfish KW - Pterois volitans KW - Salinity tolerance ER - TY - JOUR TI - Plant–animal interactions in suburban environments: implications for floral evolution AU - Irwin, Rebecca E. AU - Warren, Paige S. AU - Carper, Adrian L. AU - Adler, Lynn S. T2 - Oecologia DA - 2014/11/6/ PY - 2014/11/6/ DO - 10.1007/S00442-013-2797-2 VL - 174 IS - 3 SP - 803–815 SN - 0029-8549 1432-1939 UR - http://dx.doi.org/10.1007/S00442-013-2797-2 KW - Suburbanization KW - Floral evolution KW - Florivory KW - Nectar robbing KW - Gelsemium sempervirens ER - TY - JOUR TI - Secondary Compounds in Floral Rewards of Toxic Rangeland Plants: Impacts on Pollinators AU - Irwin, Rebecca E. AU - Cook, Daniel AU - Richardson, Leif L. AU - Manson, Jessamyn S. AU - Gardner, Dale R. T2 - Journal of Agricultural and Food Chemistry AB - The study of plant secondary chemistry has been essential in understanding plant consumption by herbivores. There is growing evidence that secondary compounds also occur in floral rewards, including nectar and pollen. Many pollinators are generalist nectar and pollen foragers and thus are exposed to an array of secondary compounds in their diet. This review documents secondary compounds in the nectar or pollen of poisonous rangeland plants of the western United States and the effects of these compounds on the behavior, performance, and survival of pollinators. Furthermore, the biochemical, physiological, and behavioral mechanisms by which pollinators cope with secondary compound consumption are discussed, drawing parallels between pollinators and herbivores. Finally, three avenues of future research on floral reward chemistry are proposed. Given that the majority of flowering plants require animals for pollination, understanding how floral reward chemistry affects pollinators has implications for plant reproduction in agricultural and rangeland habitats. DA - 2014/5/15/ PY - 2014/5/15/ DO - 10.1021/JF500521W VL - 62 IS - 30 SP - 7335-7344 J2 - J. Agric. Food Chem. LA - en OP - SN - 0021-8561 1520-5118 UR - http://dx.doi.org/10.1021/JF500521W DB - Crossref KW - alkaloid KW - nectar KW - pollen KW - pollinator KW - secondary metabolite ER - TY - JOUR TI - Modification of a seagrass community by benthic jellyfish blooms and nutrient enrichment AU - Stoner, Elizabeth W. AU - Yeager, Lauren A. AU - Sweatman, Jennifer L. AU - Sebilian, Serina S. AU - Layman, Craig A. T2 - Journal of Experimental Marine Biology and Ecology AB - 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. DA - 2014/12// PY - 2014/12// DO - 10.1016/J.JEMBE.2014.08.005 VL - 461 SP - 185-192 J2 - Journal of Experimental Marine Biology and Ecology LA - en OP - SN - 0022-0981 UR - http://dx.doi.org/10.1016/J.JEMBE.2014.08.005 DB - Crossref KW - Cassiopea spp. KW - Eutrophication KW - Global change KW - Habitat complexity KW - Jellyfish blooms KW - Thalassia testudinum ER - TY - JOUR TI - Lionfish alter benthic invertebrate assemblages in patch habitats of a subtropical estuary AU - Layman, C. A. AU - Jud, Z. R. AU - Nichols, P. T2 - Marine Biology DA - 2014/7/23/ PY - 2014/7/23/ DO - 10.1007/S00227-014-2491-X VL - 161 IS - 9 SP - 2179-2182 J2 - Mar Biol LA - en OP - SN - 0025-3162 1432-1793 UR - http://dx.doi.org/10.1007/S00227-014-2491-X DB - Crossref ER - TY - JOUR TI - Ecosystem fragmentation drives increased diet variation in an endemic livebearing fish of the Bahamas AU - Araújo, Márcio S. AU - Langerhans, R. Brian AU - Giery, Sean T. AU - Layman, Craig A. T2 - Ecology and Evolution AB - Abstract One consequence of human‐driven habitat degradation in general, and habitat fragmentation in particular, is loss of biodiversity. An often‐underappreciated aspect of habitat fragmentation relates to changes in the ecology of species that persist in altered habitats. In Bahamian wetlands, ecosystem fragmentation causes disruption of hydrological connectivity between inland fragmented wetlands and adjacent marine areas, with the consequent loss of marine piscivores from fragmented sections. We took advantage of this environmental gradient to investigate effects of ecosystem fragmentation on patterns of resource use in the livebearing fish Gambusia hubbsi (Family Poeciliidae), using both population‐ and individual‐level perspectives. We show that fragmentation‐induced release from predation led to increased G. hubbsi population densities, which consequently led to lower mean growth rates, likely as a result of higher intraspecific competition for food. This was accompanied by a broadening of dietary niches via increased interindividual diet variation, suggesting a negative effect of predation and a positive effect of intraspecific competition on the degree of diet variation in natural populations. Our results therefore indicate that habitat fragmentation can greatly impact the ecology of resilient populations, with potentially important ecological and evolutionary implications. DA - 2014/7/31/ PY - 2014/7/31/ DO - 10.1002/ECE3.1140 VL - 4 IS - 16 SP - 3298-3308 J2 - Ecol Evol LA - en OP - SN - 2045-7758 UR - http://dx.doi.org/10.1002/ECE3.1140 DB - Crossref KW - Bahamas mosquitofish KW - food webs KW - individual specialization KW - niche variation KW - predation KW - RNA/DNA ratios KW - stable isotopes ER - TY - JOUR TI - Drosophila suzukii: The Genetic Footprint of a Recent, Worldwide Invasion AU - Adrion, Jeffrey R. AU - Kousathanas, Athanasios AU - Pascual, Marta AU - Burrack, Hannah J. AU - Haddad, Nick M. AU - Bergland, Alan O. AU - Machado, Heather AU - Sackton, Timothy B. AU - Schlenke, Todd A. AU - Watada, Masayoshi AU - Wegmann, Daniel AU - Singh, Nadia D. T2 - MOLECULAR BIOLOGY AND EVOLUTION AB - Native to Asia, the soft-skinned fruit pest Drosophila suzukii has recently invaded the United States and Europe. The eastern United States represents the most recent expansion of their range, and presents an opportunity to test alternative models of colonization history. Here, we investigate the genetic population structure of this invasive fruit fly, with a focus on the eastern United States. We sequenced six X-linked gene fragments from 246 individuals collected from a total of 12 populations. We examine patterns of genetic diversity within and between populations and explore alternative colonization scenarios using approximate Bayesian computation. Our results indicate high levels of nucleotide diversity in this species and suggest that the recent invasions of Europe and the continental United States are independent demographic events. More broadly speaking, our results highlight the importance of integrating population structure into demographic models, particularly when attempting to reconstruct invasion histories. Finally, our simulation results illustrate the general challenge in reconstructing invasion histories using genetic data and suggest that genome-level data are often required to distinguish among alternative demographic scenarios. DA - 2014/12// PY - 2014/12// DO - 10.1093/molbev/msu246 VL - 31 IS - 12 SP - 3148-3163 SN - 1537-1719 KW - Drosophila suzukii KW - population genetics KW - invasion KW - pest ER - TY - JOUR TI - Unexpected phenological responses of butterflies to the interaction of urbanization and geographic temperature AU - Diamond, Sarah E. AU - Cayton, Heather AU - Wepprich, Tyson AU - Jenkins, Clinton N. AU - Dunn, Robert R. AU - Haddad, Nick M. AU - Ries, Leslie T2 - ECOLOGY AB - Urbanization and global climate change can profoundly alter biological systems, yet scientists often analyze their effects separately. We test how the timing of life cycle events (phenology) is jointly influenced by these two components of global change. To do so, we use a long‐term phenological data set of 20 common butterfly species from 83 sites across the state of Ohio, USA, with sites that range from rural undeveloped areas to moderately sized cities. These sites span a latitudinal gradient in mean temperature of several °C, mimicking the range of projected global climate warming effects through the end of the century. Although shifts toward earlier phenology are typical of species' responses to either global climate change or urbanization, we found that their interaction delayed several Ohio butterfly species' first appearance and peak abundance phenology. Exploitative species exhibited smaller delays in first appearance and peak abundance phenology in areas that were urbanized and geographically warm. Our results show that phenological responses to urbanization are contingent upon geographic variation in temperature, and that the impacts of urbanization and global climate change should be considered simultaneously when developing forecasts of biological responses to environmental change. DA - 2014/9// PY - 2014/9// DO - 10.1890/13-1848.1 VL - 95 IS - 9 SP - 2613-2621 SN - 1939-9170 KW - anthropogenic change KW - citizen science KW - global climate change KW - impervious surface KW - Lepidoptera KW - nonadditive effects KW - phenology KW - physiology KW - temperature KW - trait-based modeling ER - TY - JOUR TI - Landscape corridors can increase invasion by an exotic species and reduce diversity of native species AU - Resasco, J. AU - Haddad, N. M. AU - Orrock, J. L. AU - Shoemaker, D. AU - Brudvig, T. A. AU - Damschen, E. I. AU - Tewksbury, J. J. AU - Levey, D. J. T2 - Ecology AB - Landscape corridors are commonly used to mitigate negative effects of habitat fragmentation, but concerns persist that they may facilitate the spread of invasive species. In a replicated landscape experiment of open habitat, we measured effects of corridors on the invasive fire ant, Solenopsis invicta , and native ants. Fire ants have two social forms: polygyne, which tend to disperse poorly but establish at high densities, and monogyne, which disperse widely but establish at lower densities. In landscapes dominated by polygyne fire ants, fire ant abundance was higher and native ant diversity was lower in habitat patches connected by corridors than in unconnected patches. Conversely, in landscapes dominated by monogyne fire ants, connectivity had no influence on fire ant abundance and native ant diversity. Polygyne fire ants dominated recently created landscapes, suggesting that these corridor effects may be transient. Our results suggest that corridors can facilitate invasion and they highlight the importance of considering species' traits when assessing corridor utility. DA - 2014/// PY - 2014/// DO - 10.1890/14-0169.1 VL - 95 IS - 8 SP - 2033-2039 ER - TY - JOUR TI - Defining and Evaluating the Umbrella Species Concept for Conserving and Restoring Landscape Connectivity AU - Breckheimer, Ian AU - Haddad, Nick M. AU - Morris, William F. AU - Trainor, Anne M. AU - Fields, William R. AU - Jobe, R. Todd AU - Hudgens, Brian R. AU - Moody, Aaron AU - Walters, Jeffrey R. T2 - CONSERVATION BIOLOGY AB - Conserving or restoring landscape connectivity between patches of breeding habitat is a common strategy to protect threatened species from habitat fragmentation. By managing connectivity for some species, usually charismatic vertebrates, it is often assumed that these species will serve as conservation umbrellas for other species. We tested this assumption by developing a quantitative method to measure overlap in dispersal habitat of 3 threatened species-a bird (the umbrella), a butterfly, and a frog-inhabiting the same fragmented landscape. Dispersal habitat was determined with Circuitscape, which was parameterized with movement data collected for each species. Despite differences in natural history and breeding habitat, we found substantial overlap in the spatial distributions of areas important for dispersal of this suite of taxa. However, the intuitive umbrella species (the bird) did not have the highest overlap with other species in terms of the areas that supported connectivity. Nevertheless, we contend that when there are no irreconcilable differences between the dispersal habitats of species that cohabitate on the landscape, managing for umbrella species can help conserve or restore connectivity simultaneously for multiple threatened species with different habitat requirements. DA - 2014/12// PY - 2014/12// DO - 10.1111/cobi.12362 VL - 28 IS - 6 SP - 1584-1593 SN - 1523-1739 KW - circuit theory KW - corridor KW - dispersal KW - landscape connectivity KW - modeling KW - surrogate species KW - conectividad de paisajes KW - corredor KW - dispersion KW - especies sustitutas KW - modelado KW - teoria de circuitos ER - TY - JOUR TI - The hidden history of the snowshoe hare, Lepus americanus: extensive mitochondrial DNA introgression inferred from multilocus genetic variation AU - Melo-Ferreira, Jose AU - Seixas, Fernando A. AU - Cheng, Ellen AU - Mills, L. Scott AU - Alves, Paulo C. T2 - MOLECULAR ECOLOGY AB - Abstract Hybridization drives the evolutionary trajectory of many species or local populations, and assessing the geographic extent and genetic impact of interspecific gene flow may provide invaluable clues to understand population divergence or the adaptive relevance of admixture. In N orth A merica, hares ( L epus spp.) are key species for ecosystem dynamics and their evolutionary history may have been affected by hybridization. Here we reconstructed the speciation history of the three most widespread hares in N orth A merica – the snowshoe hare ( L epus americanus ), the white‐tailed jackrabbit ( L . townsendii ) and the black‐tailed jackrabbit ( L . californicus ) – by analysing sequence variation at eight nuclear markers and one mitochondrial DNA (mt DNA ) locus (6240 bp; 94 specimens). A multilocus–multispecies coalescent‐based phylogeny suggests that L . americanus diverged ~2.7 Ma and that L . californicus and L . townsendii split more recently (~1.2 Ma). Within L . americanus, a deep history of cryptic divergence (~2.0 Ma) was inferred, which coincides with major speciation events in other N orth A merican species. While the isolation‐with‐migration model suggested that nuclear gene flow was generally rare or absent among species or major genetic groups, coalescent simulations of mt DNA divergence revealed historical mt DNA introgression from L . californicus into the P acific N orthwest populations of L . americanus . This finding marks a history of past reticulation between these species, which may have affected other parts of the genome and influence the adaptive potential of hares during climate change. DA - 2014/9// PY - 2014/9// DO - 10.1111/mec.12886 VL - 23 IS - 18 SP - 4617-4630 SN - 1365-294X KW - coalescent KW - cryptic divergence KW - hares and jackrabbits KW - lagomorphs KW - reticulate evolution KW - species tree ER - TY - JOUR TI - Does landscape context mediate the nature of density dependence for a coral reef fish? AU - Yeager, Lauren A. AU - Stoner, Elizabeth W. AU - Zapata, Martha J. AU - Layman, Craig A. T2 - ECOLOGICAL APPLICATIONS AB - 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. DA - 2014/10// PY - 2014/10// DO - 10.1890/13-2231.1 VL - 24 IS - 7 SP - 1833-1841 SN - 1939-5582 KW - artificial reef KW - competition KW - condition KW - food web KW - group behavior KW - Haemulon plumierii KW - seagrass ER - TY - JOUR TI - Diet variation of a generalist fish predator, grey snapper Lutjanus griseus, across an estuarine gradient: trade-offs of quantity for quality? AU - Yeager, L. A. AU - Layman, C. A. AU - Hammerschlag-Peyer, C. M. T2 - JOURNAL OF FISH BIOLOGY AB - 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. DA - 2014/8// PY - 2014/8// DO - 10.1111/jfb.12416 VL - 85 IS - 2 SP - 264-277 SN - 1095-8649 KW - compensatory feeding KW - food web KW - growth KW - prey quality KW - prey quantity ER - TY - JOUR TI - Potential Negative Ecological Effects of Corridors AU - Haddad, N. M. AU - Brudvig, L. A. AU - Damschen, E. I. AU - Evans, D. M. AU - Johnson, B. L. AU - Levey, D. J. AU - Orrock, J. L. AU - Resasco, J. AU - Sullivan, L. L. AU - Tewksbury, J. J. AU - Wagner, S. A. AU - Weldon, A. J. T2 - Conservation Biology AB - Despite many studies showing that landscape corridors increase dispersal and species richness for disparate taxa, concerns persist that corridors can have unintended negative effects. In particular, some of the same mechanisms that underlie positive effects of corridors on species of conservation interest may also increase the spread and impact of antagonistic species (e.g., predators and pathogens), foster negative effects of edges, increase invasion by exotic species, increase the spread of unwanted disturbances such as fire, or increase population synchrony and thus reduce persistence. We conducted a literature review and meta-analysis to evaluate the prevalence of each of these negative effects. We found no evidence that corridors increase unwanted disturbance or non-native species invasion; however, these have not been well-studied concerns (1 and 6 studies, respectively). Other effects of corridors were more often studied and yielded inconsistent results; mean effect sizes were indistinguishable from zero. The effect of edges on abundances of target species was as likely to be positive as negative. Corridors were as likely to have no effect on antagonists or population synchrony as they were to increase those negative effects. We found 3 deficiencies in the literature. First, despite studies on how corridors affect predators, there are few studies of related consequences for prey population size and persistence. Second, properly designed studies of negative corridor effects are needed in natural corridors at scales larger than those achievable in experimental systems. Third, studies are needed to test more targeted hypotheses about when corridor-mediated effects on invasive species or disturbance may be negative for species of management concern. Overall, we found no overarching support for concerns that construction and maintenance of habitat corridors may result in unintended negative consequences. Negative edge effects may be mitigated by widening corridors or softening edges between corridors and the matrix. Other negative effects are relatively small and manageable compared with the large positive effects of facilitating dispersal and increasing diversity of native species. DA - 2014/// PY - 2014/// DO - 10.1111/cobi.12323 VL - 28 IS - 5 SP - 1178-1187 ER - TY - JOUR TI - What Doesn't Kill You Makes You Wary? Effect of Repeated Culling on the Behaviour of an Invasive Predator AU - Cote, Isabelle M. AU - Darling, Emily S. AU - Malpica-Cruz, Luis AU - Smith, Nicola S. AU - Green, Stephanie J. AU - Curtis-Quick, Jocelyn AU - Layman, Craig T2 - PLOS ONE AB - 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. DA - 2014/4/4/ PY - 2014/4/4/ DO - 10.1371/journal.pone.0094248 VL - 9 IS - 4 SP - SN - 1932-6203 ER - TY - JOUR TI - How fragmentation and corridors affect wind dynamics and seed dispersal in open habitats AU - Damschen, Ellen I. AU - Baker, Dirk V. AU - Bohrer, Gil AU - Nathan, Ran AU - Orrock, John L. AU - Turner, Jay R. AU - Brudvig, Lars A. AU - Haddad, Nick M. AU - Levey, Douglas J. AU - Tewksbury, Joshua J. T2 - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA AB - Significance Understanding how widespread human-induced global changes are affecting the movement and dispersal of organisms is critical for maintaining species diversity and making sound land management decisions. In contrast with animal-dispersed species, little is known about how wind-dispersed species are affected by conservation strategies such as corridors. We use a combination of mechanistic models and field data to show that habitat corridors alter wind dynamics in a way that promotes seed dispersal and appears to increase plant diversity. Wind direction also interacts with landscape orientation to determine when corridors can provide connectivity. DA - 2014/3/4/ PY - 2014/3/4/ DO - 10.1073/pnas.1308968111 VL - 111 IS - 9 SP - 3484-3489 SN - 0027-8424 KW - diversity KW - plant community KW - habitat structure KW - reserve design KW - long-distance dispersal ER - TY - JOUR TI - Conservation implications of the evolutionary history and genetic diversity hotspots of the snowshoe hare AU - Cheng, Ellen AU - Hodges, Karen E. AU - Melo-Ferreira, Jose AU - Alves, Paulo C. AU - Mills, L. Scott T2 - MOLECULAR ECOLOGY AB - Abstract With climate warming, the ranges of many boreal species are expected to shift northward and to fragment in southern peripheral ranges. To understand the conservation implications of losing southern populations, we examined range‐wide genetic diversity of the snowshoe hare ( Lepus americanus ), an important prey species that drives boreal ecosystem dynamics. We analysed microsatellite (8 loci) and mitochondrial DNA sequence (cytochrome b and control region) variation in almost 1000 snowshoe hares. A hierarchical structure analysis of the microsatellite data suggests initial subdivision in two groups, Boreal and southwestern. The southwestern group further splits into Greater Pacific Northwest and U.S. Rockies. The genealogical information retrieved from mt DNA is congruent with the three highly differentiated and divergent groups of snowshoe hares. These groups can correspond with evolutionarily significant units that might have evolved in separate refugia south and east of the Pleistocene ice sheets. Genetic diversity was highest at mid‐latitudes of the species' range, and genetic uniqueness was greatest in southern populations, consistent with substructuring inferred from both mt DNA and microsatellite analyses at finer levels of analysis. Surprisingly, snowshoe hares in the Greater Pacific Northwest mt DNA lineage were more closely related to black‐tailed jackrabbits (Lepus californicus ) than to other snowshoe hares, which may result from secondary introgression or shared ancestral polymorphism. Given the genetic distinctiveness of southern populations and minimal gene flow with their northern neighbours, fragmentation and loss of southern boreal habitats could mean loss of many unique alleles and reduced evolutionary potential. DA - 2014/6// PY - 2014/6// DO - 10.1111/mec.12790 VL - 23 IS - 12 SP - 2929-2942 SN - 1365-294X KW - climate change KW - core-periphery KW - evolutionarily significant units KW - landscape genetics KW - Lepus americanus KW - phylogeography ER - TY - JOUR TI - Provision of ecosystem services by human-made structures in a highly impacted estuary AU - Layman, Craig A. AU - Jud, Zachary R. AU - Archer, Stephanie K. AU - Riera, David T2 - ENVIRONMENTAL RESEARCH LETTERS AB - 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. DA - 2014/4// PY - 2014/4// DO - 10.1088/1748-9326/9/4/044009 VL - 9 IS - 4 SP - SN - 1748-9326 KW - ecosystem services KW - estuary KW - filtration KW - oysters KW - urbanization ER -