@article{tharp_hostetter_paxton_taylor_buckel_2024, title={Artificial structure selection by economically important reef fishes at North Carolina artificial reefs}, volume={11}, ISSN={["2296-7745"]}, DOI={10.3389/fmars.2024.1373494}, abstractNote={Artificial reefs can play an important role in marine fisheries management by supplementing or enhancing natural habitats. Despite their increased use in recent years, the choice of structures used at artificial reefs remains largely haphazard due to the lack of information on reef structure performance. Few studies have examined the use of different artificial reef structures by individual fish. From 2021-2022, we acoustically tagged 72 black sea bass ( Centropristis striata ), 34 gag ( Mycteroperca mircrolepis ), 27 greater amberjack ( Seriola dumerili ), nine almaco jack ( S. rivoliana ), and eight red snapper ( Lutjanus campechanus ) on four artificial reef complexes near Cape Lookout, North Carolina, U.S. Available artificial reef structures consisted of materials of various sizes and heights made of concrete and metal. We tracked tagged fish using a fine-scale positioning system for ~100 days. Black sea bass exhibited high site fidelity to the artificial structure where we caught them, rarely moving away from that structure. The limited movement resulted in low transition probabilities; we conclude that black sea bass do not select for particular artificial structures. Gag and red snapper moved greater distances away from artificial structures and routinely moved between them. Greater amberjack and almaco jack moved the most within the complexes displaying circling behavior around individual structures and were the only species that regularly moved off the artificial reef complexes. Greater amberjack movements away from artificial sites were most commonly directed to surrounding shipwrecks. Whereas gag, red snapper, almaco jack, and greater amberjack used all available structures, they consistently selected for high relief structures, such as vessels, more than other structures. These results will be useful to managers charged with decisions on what types of structures to place at artificial reef complexes to supplement or enhance habitat for economically important fishes.}, journal={FRONTIERS IN MARINE SCIENCE}, author={Tharp, Ryan M. and Hostetter, Nathan J. and Paxton, Avery B. and Taylor, J. Christopher and Buckel, Jeffrey A.}, year={2024}, month={Apr} }
 @article{rivera_henderson_lam_hostetter_collazo_bell_2024, title={High-Quality, Chromosome-Level Reference Genomes of the Viviparous Caribbean Skinks Spondylurus nitidus and S. culebrae}, volume={16}, ISSN={["1759-6653"]}, url={https://doi.org/10.1093/gbe/evae079}, DOI={10.1093/gbe/evae079}, abstractNote={Abstract New World mabuyine skinks are a diverse radiation of morphologically cryptic lizards with unique reproductive biologies. Recent studies examining population-level data (morphological, ecological, and genomic) have uncovered novel biodiversity and phenotypes, including the description of dozens of new species and insights into the evolution of their highly complex placental structures. Beyond the potential for this diverse group to serve as a model for the evolution of viviparity in lizards, much of the taxonomic diversity is concentrated in regions experiencing increasing environmental instability from climate and anthropogenic change. Consequently, a better understanding of genome structure and diversity will be an important tool in the adaptive management and conservation of this group. Skinks endemic to Caribbean islands are particularly vulnerable to global change with several species already considered likely extinct and several remaining species either endangered or threatened. Combining PacBio long-read sequencing, Hi-C, and RNAseq data, here we present the first genomic resources for this group by describing new chromosome-level reference genomes for the Puerto Rican Skink Spondylurus nitidus and the Culebra Skink S. culebrae. Results indicate two high quality genomes, both ∼1.4 Gb, assembled nearly telomere to telomere with complete mitochondrion assembly and annotation.}, number={5}, journal={GENOME BIOLOGY AND EVOLUTION}, author={Rivera, Danielle and Henderson, James B. and Lam, Athena W. and Hostetter, Nathan J. and Collazo, Jaime A. and Bell, Rayna C.}, editor={Zhou, QiEditor}, year={2024}, month={May} }
 @article{adams_hostetter_link_converse_2024, title={Identifying Pareto-efficient eradication strategies for invasive populations}, volume={9}, ISSN={["1755-263X"]}, DOI={10.1111/conl.13051}, abstractNote={Abstract Invasive species are a major cause of biodiversity loss and are notoriously expensive and challenging to manage. We developed a decision‐analytic framework for evaluating invasive species removal strategies, given objectives of maximizing eradication probability and minimizing costs. The framework uses an existing estimation model for spatially referenced removal data—one of the most accessible types of invasive species data—to obtain estimates of population growth rate, movement probability, and detection probability. We use these estimates in simulations to identify Pareto‐efficient strategies—strategies where increases in eradication probability cannot be obtained without increases in cost—from a set of proposed strategies. We applied the framework post hoc to a successful eradication of veiled chameleons ( Chamaeleo calyptratus ) and identified the potential for substantial improvements in efficiency. Our approach provides managers and policymakers with tools to identify cost‐effective strategies for a range of invasive species using only prior knowledge or data from initial physical removals.}, journal={CONSERVATION LETTERS}, author={Adams, Amy A. Yackel and Hostetter, Nathan J. and Link, William A. and Converse, Sarah J.}, year={2024}, month={Sep} }
 @article{rivera_zegarra_puente-rolon_arocho-hernandez_hostetter_collazo_bell_2024, title={Multiple records of the introduced parthenogenetic Smooth-scaled Tegulet, <i>Gymnophthalmus underwoodi</i> Grant 1958, in Puerto Rico}, url={https://doi.org/10.17161/randa.v31i1.21466}, DOI={10.17161/randa.v31i1.21466}, abstractNote={The introduction of invasive species to islands can be devastating to local biota. While many invasive species’successful colonization of new habitats can be attributed to features like high fecundity or low mate selectivity,parthenogenetic species pose a unique threat in their ability to reproduce asexually at high rates. The Smooth-scaledTegulet (Gymnophthalmus underwoodi), first described from Barbados in the 1950s, has since been documented as anintroduced species across additional Lesser and Greater Antillean islands as well as northwestern Brazil and Venezuela.Herein we report multiple individuals from Puerto Rico, including the first genetic records, which indicate that theindividuals on this island are most closely related to populations recorded from Brazil and Montserrat. Additionalgenetic information is necessary to determine the timing and migration of this species across the Caribbean. Regardless,the continued geographic expansion of this parthenogen across the Caribbean could present a threat to local fauna.}, journal={Reptiles & Amphibians}, author={Rivera, Danielle and Zegarra, Jan and Puente-Rolon, Alberto and Arocho-Hernandez, Nahira and Hostetter, Nathan and Collazo, Jaime and Bell, Rayna}, year={2024}, month={Mar} }
 @article{bacheler_iii_tarnecki_shertzer_buckel_hostetter_pacifici_zulian_bubley_2025, title={Spatiotemporal dynamics and habitat use of red snapper (<i>Lutjanus</i> <i>campechanus</i>) on the southeastern United States Atlantic continental shelf}, volume={281}, ISSN={["1872-6763"]}, DOI={10.1016/j.fishres.2024.107200}, journal={FISHERIES RESEARCH}, author={Bacheler, Nathan M. and Iii, William F. Patterson and Tarnecki, Joseph H. and Shertzer, Kyle W. and Buckel, Jeffrey A. and Hostetter, Nathan J. and Pacifici, Krishna and Zulian, Viviane and Bubley, Walter J.}, year={2025}, month={Jan} }
 @article{coleman_fox_horne_hostetter_madsen_o'brien_park_stence_secor_2024, title={Spawning run estimates and phenology for an extremely small population of Atlantic Sturgeon in the Marshyhope Creek-Nanticoke River system, Chesapeake Bay}, volume={16}, ISSN={["1942-5120"]}, DOI={10.1002/mcf2.10292}, abstractNote={Abstract Objective Once thought to be extirpated from the Chesapeake Bay, fall spawning runs of Atlantic Sturgeon Acipenser oxyrinchus have been rediscovered in the Marshyhope Creek (MC)–Nanticoke River (NR) system of Maryland, United States. High recapture rates in past telemetry surveys suggested a small population in the two connected tributaries. This study aims to generate estimates of abundance and understand within system connectivity for spawning runs in 2020 and 2021. Methods Data from mobile side‐scan sonar surveys and detections of acoustically tagged adults on stationary telemetry receivers were analyzed in an integrated model to estimate spawning season abundance and examine run timing and system connectivity for this population. An array of acoustic receivers was deployed throughout the MC–NR system to monitor the movement of tagged fish during the spawning run period from mid‐August to late October. Side‐scan sonar surveys were conducted weekly in September in an area of high spawner aggregation to generate count data on spawning run abundance. Result In 2020 and 2021, 32 (95% credible interval [CRI] = 23–47) and 70 (95% CRI = 49–105) Atlantic Sturgeon, respectively, used the MC–NR system. The lower estimate for 2020 coincided with an earlier end to the spawning run related to cooler September temperatures in that year. Conclusion In both years, high spawning run connectivity between MC and the upper NR was observed. Overall, run estimates supported previous hypotheses that the MC–NR system supports a very small population and that both MC and the upper NR serve as important areas for spawning activity.}, number={3}, journal={MARINE AND COASTAL FISHERIES}, author={Coleman, Nicholas and Fox, Dewayne and Horne, Ashlee and Hostetter, Nathan J. and Madsen, John and O'Brien, Michael and Park, Ian and Stence, Chuck and Secor, David}, year={2024}, month={Jun} }
 @article{hostetter_evans_payton_roby_lyons_collis_2023, title={A Review of Factors Affecting the Susceptibility of Juvenile Salmonids to Avian Predation}, volume={2}, ISSN={["1548-8675"]}, url={https://doi.org/10.1002/nafm.10862}, DOI={10.1002/nafm.10862}, abstractNote={AbstractWe reviewed studies of piscivorous colonial waterbird predation on juvenile salmonids to synthesize current knowledge of factors affecting fish susceptibility to avian predators. Specifically, we examined peer‐reviewed publications and reports from academic, governmental, and nongovernmental agencies to identify commonalities and differences in susceptibility of salmonids to avian predation, with a focus on mark–recovery studies in the Columbia River basin. Factors hypothesized to influence salmonid susceptibility to avian predation were grouped into four general categories: (1) salmonid species and populations, (2) environmental factors, (3) prey density, predator density, and migration timing, and (4) prey characteristics. Our review focused on predation by Caspian terns Hydroprogne caspia, double‐crested cormorants Nannopterum auritum, and gull species Larus spp. as these are the most well‐studied avian predators of salmonids. Results indicated that predator–prey interactions varied across salmonid species and populations and species of avian predator. Inferences across studies supported multiple hypotheses regarding predator–prey dynamics, including environmental factors that influence prey exposure to predators (e.g., river flows, turbidity, alternative prey), variation in predator and prey abundances, predator characteristics (e.g., foraging behavior, colony location), and prey characteristics (e.g., fish length, condition). Mark–recovery studies of avian predation on fish populations have greatly improved our understanding of the factors affecting fish susceptibility to avian predation, the relative contributions of abiotic and biotic factors to predation susceptibility, and the extent to which avian predation affects fish survival and the viability of prey populations. Future studies that jointly model predation and survival and the factors affecting those processes will further broaden our understanding of predator–prey dynamics and directly evaluate the effects of predation on prey population dynamics.}, journal={NORTH AMERICAN JOURNAL OF FISHERIES MANAGEMENT}, author={Hostetter, Nathan J. J. and Evans, Allen F. F. and Payton, Quinn and Roby, Daniel D. D. and Lyons, Donald E. E. and Collis, Ken}, year={2023}, month={Feb} }
 @article{evans_payton_hostetter_collis_cramer_roby_2022, title={Cumulative effects of piscivorous colonial waterbirds on juvenile salmonids: A multi predator-prey species evaluation}, volume={17}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0272875}, abstractNote={We investigated the cumulative effects of predation by piscivorous colonial waterbirds on the survival of multiple salmonid (Oncorhynchusspp.) populations listed under the U.S. Endangered Species Act (ESA) and determined what proportion of all sources of fish mortality (1 –survival) were due to birds in the Columbia River basin, USA. Anadromous juvenile salmonids (smolts) were exposed to predation by Caspian terns (Hydroprogne caspia), double-crested cormorants (Nannopterum auritum), California gulls (Larus californicus), and ring-billed gulls (L.delawarensis), birds known to consume both live and dead fish. Avian consumption and survival probabilities (proportion of available fish consumed or alive) were estimated for steelhead trout (O.mykiss), yearling Chinook salmon (O.tshawytscha), sub-yearling Chinook salmon, and sockeye salmon (O.nerka) during out-migration from the lower Snake River to the Pacific Ocean during an 11-year study period (2008–2018). Results indicated that probabilities of avian consumption varied greatly across salmonid populations, bird species, colony location, river reach, and year. Cumulative consumption probabilities (consumption by birds from all colonies combined) were consistently the highest for steelhead, with annual estimates ranging from 0.22 (95% credible interval = 0.20–0.26) to 0.51 (0.43–0.60) of available smolts. The cumulative effects of avian consumption were significantly lower for yearling and sub-yearling Chinook salmon, with consumption probabilities ranging annually from 0.04 (0.02–0.07) to 0.10 (0.07–0.15) and from 0.06 (0.3–0.09) to 0.15 (0.10–0.23), respectively. Avian consumption probabilities for sockeye salmon smolts was generally higher than for Chinook salmon smolts, but lower than for steelhead smolts, ranging annually from 0.08 (0.03–0.22) to 0.25 (0.14–0.44). Although annual consumption probabilities for birds from certain colonies were more than 0.20 of available smolts, probabilities from other colonies were less than 0.01 of available smolts, indicating that not all colonies of birds posed a substantial risk to smolt mortality. Consumption probabilities were lowest for small colonies and for colonies located a considerable distance from the Snake and Columbia rivers. Total mortality attributed to avian consumption was relatively small for Chinook salmon (less than 10%) but was the single greatest source of mortality for steelhead (greater than 50%) in all years evaluated. Results suggest that the potential benefits to salmonid populations of managing birds to reduce smolt mortality would vary widely depending on the salmonid population, the species of bird, and the size and location of the breeding colony.}, number={8}, journal={PLOS ONE}, author={Evans, Allen F. and Payton, Quinn and Hostetter, Nathan J. and Collis, Ken and Cramer, Bradley M. and Roby, Daniel D.}, year={2022}, month={Aug} }
 @article{gardner_mcclintock_converse_hostetter_2022, title={Integrated animal movement and spatial capture-recapture models: Simulation, implementation, and inference}, volume={7}, ISSN={["1939-9170"]}, url={https://doi.org/10.1002/ecy.3771}, DOI={10.1002/ecy.3771}, abstractNote={AbstractOver the last decade, spatial capture–recapture (SCR) models have become widespread for estimating demographic parameters in ecological studies. However, the underlying assumptions about animal movement and space use are often not realistic. This is a missed opportunity because interesting ecological questions related to animal space use, habitat selection, and behavior cannot be addressed with most SCR models, despite the fact that the data collected in SCR studies — individual animals observed at specific locations and times — can provide a rich source of information about these processes and how they relate to demographic rates. We developed SCR models that integrated more complex movement processes that are typically inferred from telemetry data, including a simple random walk, correlated random walk (i.e., short‐term directional persistence), and habitat‐driven Langevin diffusion. We demonstrated how to formulate, simulate from, and fit these models with standard SCR data using data‐augmented Bayesian analysis methods. We evaluated their performance through a simulation study, in which we varied the detection, movement, and resource selection parameters. We also examined different numbers of sampling occasions and assessed performance gains when including auxiliary location data collected from telemetered individuals. Across all scenarios, the integrated SCR movement models performed well in terms of abundance, detection, and movement parameter estimation. We found little difference in bias for the simple random walk model when reducing the number of sampling occasions fromT= 25 toT= 15. We found some bias in movement parameter estimates under several of the correlated random walk scenarios, but incorporating auxiliary location data improved parameter estimates and significantly improved mixing during model fitting. The Langevin movement model was able to recover resource selection parameters from standard SCR data, which is particularly appealing because it explicitly links the individual‐level movement process with habitat selection and population density. We focused on closed population models, but the movement models developed here can be extended to open SCR models. The movement process models could also be easily extended to accommodate additional “building blocks” of random walks, such as central tendency (e.g., territoriality) or multiple movement behavior states, thereby providing a flexible and coherent framework for linking animal movement behavior to population dynamics, density, and distribution.}, journal={ECOLOGY}, author={Gardner, Beth and McClintock, Brett T. and Converse, Sarah J. and Hostetter, Nathan J.}, year={2022}, month={Jul} }
 @article{hostetter_regehr_wilson_royle_converse_2022, title={Modeling spatiotemporal abundance and movement dynamics using an integrated spatial capture–recapture movement model}, url={https://doi.org/10.1002/ecy.3772}, DOI={10.1002/ecy.3772}, abstractNote={AbstractAnimal movement is a fundamental ecological process affecting the survival and reproduction of individuals, the structure of populations, and the dynamics of communities. Methods to quantify animal movement and spatiotemporal abundances, however, are generally separate and therefore omit linkages between individual‐level and population‐level processes. We describe an integrated spatial capture–recapture (SCR) movement model to jointly estimate (1) the number and distribution of individuals in a defined spatial region and (2) movement of those individuals through time. We applied our model to a study of polar bears (Ursus maritimus) in a 28,125 km2 survey area of the eastern Chukchi Sea, USA in 2015 that incorporated capture–recapture and telemetry data. In simulation studies, the model provided unbiased estimates of movement, abundance, and detection parameters using a bivariate normal random walk and correlated random walk movement process. Our case study provided detailed evidence of directional movement persistence for both male and female bears, where individuals regularly traversed areas larger than the survey area during the 36‐day study period. Scaling from individual‐ to population‐level inferences, we found that densities varied from <0.75 bears/625 km2 grid cell/day in nearshore cells to 1.6–2.5 bears/grid cell/day for cells surrounded by sea ice. Daily abundance estimates ranged from 53 to 69 bears, with no trend across days. The cumulative number of unique bears that used the survey area increased through time due to movements into and out of the area, resulting in an estimated 171 individuals using the survey area during the study (95% credible interval 124–250). Abundance estimates were similar to a previous multiyear integrated population model using capture–recapture and telemetry data (2008–2016; Regehr et al., Scientific Reports 8:16780, 2018). Overall, the SCR–movement model successfully quantified both individual‐ and population‐level space use, including the effects of landscape characteristics on movement, abundance, and detection, while linking the movement and abundance processes to directly estimate density within a prescribed spatial region and temporal period. Integrated SCR–movement models provide a generalizable approach to incorporate greater movement realism into population dynamics and link movement to emergent properties including spatiotemporal densities and abundances.}, journal={Ecology}, author={Hostetter, Nathan J. and Regehr, Eric V. and Wilson, Ryan R. and Royle, J. Andrew and Converse, Sarah J.}, year={2022}, month={Oct} }
 @article{hostetter_payton_roby_collis_evans_2022, title={Predation probabilities and functional responses: How piscivorous waterbirds respond to pulses in fish abundance}, volume={13}, ISSN={["2150-8925"]}, url={https://doi.org/10.1002/ecs2.4220}, DOI={10.1002/ecs2.4220}, abstractNote={AbstractHow predators respond to changes in prey abundance (i.e., functional responses) is foundational to consumer–resource interactions, predator–prey dynamics, and the stability of predator–prey systems. Predation by piscivorous waterbirds on out‐migrating juvenile steelhead trout (Oncorhynchus mykiss) is considered a factor affecting the recovery of multiple Endangered Species Act‐listed steelhead populations in the Columbia River basin. Waterbird functional responses, however, may vary by predator species and location, with important implications to predator management strategies. We used a 13‐year dataset on waterbird abundance across seven breeding colonies (three Caspian tern [Hydroprogne caspia], two double‐crested cormorant [Nannopterum auritum], and two California and ring‐billed gull [Larus californicusandLarus delawarensis] colonies) and steelhead tag‐recovery data (>645,000 tagged and >32,000 recovered steelhead) to quantify weekly predation probabilities and functional responses across waterbird species, colonies, and years. Weekly predation probabilities were highly variable, ranging from 0.01 to 0.30 at tern colonies, 0.01 to 0.20 at cormorant colonies, and 0.03 to 0.13 at gull colonies. Per capita predation probabilities were an order of magnitude higher at inland tern and cormorant colonies relative to estuary colonies of the same species. Terns displayed Type II functional responses across colonies and years, where predation probabilities peaked at low steelhead abundances and declined as steelhead abundance increased (i.e., predator swamping). Cormorants nesting at the large estuary colony (several thousand birds) displayed a Type III functional response, but cormorants nesting at the smaller inland colony (several hundred birds) displayed a Type II response. Consumption probabilities of steelhead by gulls remained consistent across a large range of steelhead availability, suggesting a Type I or a Type III functional response, but a lack of colony abundance data prevented quantifying functional responses. The level of tern predation combined with Type II functional responses indicate possible population‐level impacts that could destabilize small or declining prey populations. Conversely, the apparent Type III functional responses of gulls and estuary nesting cormorants are indicative of prey switching behaviors targeted at periods of high steelhead abundance. Our results illustrate the complexity of predator–prey interactions and the importance of quantifying predator‐ and location‐specific functional responses when predicting the efficacy of management strategies to enhance prey populations.}, number={9}, journal={ECOSPHERE}, author={Hostetter, Nathan J. and Payton, Quinn and Roby, Daniel D. and Collis, Ken and Evans, Allen F.}, year={2022}, month={Sep} }
 @article{hostetter_lunn_richardson_regehr_converse_2021, title={Age-structured Jolly-Seber model expands inference and improves parameter estimation from capture-recapture data}, volume={16}, ISSN={["1932-6203"]}, url={https://doi.org/10.1371/journal.pone.0252748}, DOI={10.1371/journal.pone.0252748}, abstractNote={Understanding the influence of individual attributes on demographic processes is a key objective of wildlife population studies. Capture-recapture and age data are commonly collected to investigate hypotheses about survival, reproduction, and viability. We present a novel age-structured Jolly-Seber model that incorporates age and capture-recapture data to provide comprehensive information on population dynamics, including abundance, age-dependent survival, recruitment, age structure, and population growth rates. We applied our model to a multi-year capture-recapture study of polar bears (Ursus maritimus) in western Hudson Bay, Canada (2012–2018), where management and conservation require a detailed understanding of how polar bears respond to climate change and other factors. In simulation studies, the age-structured Jolly-Seber model improved precision of survival, recruitment, and annual abundance estimates relative to standard Jolly-Seber models that omit age information. Furthermore, incorporating age information improved precision of population growth rates, increased power to detect trends in abundance, and allowed direct estimation of age-dependent survival and changes in annual age structure. Our case study provided detailed evidence for senescence in polar bear survival. Median survival estimates were lower (<0.95) for individuals aged <5 years, remained high (>0.95) for individuals aged 7–22 years, and subsequently declined to near zero for individuals >30 years. We also detected cascading effects of large recruitment classes on population age structure, which created major shifts in age structure when these classes entered the population and then again when they reached prime breeding ages (10–15 years old). Overall, age-structured Jolly-Seber models provide a flexible means to investigate ecological and evolutionary processes that shape populations (e.g., via senescence, life expectancy, and lifetime reproductive success) while improving our ability to investigate population dynamics and forecast population changes from capture-recapture data.}, number={6}, journal={PLOS ONE}, author={Hostetter, Nathan J. and Lunn, Nicholas J. and Richardson, Evan S. and Regehr, Eric V. and Converse, Sarah J.}, editor={Goswami, Varun R.Editor}, year={2021}, month={Jun} }
 @article{regehr_runge_duyke_wilson_polasek_rode_hostetter_converse_2021, title={Demographic risk assessment for a harvested species threatened by climate change: polar bears in the Chukchi Sea}, url={https://doi.org/10.1002/eap.2461}, DOI={10.1002/eap.2461}, abstractNote={AbstractClimate change threatens global biodiversity. Many species vulnerable to climate change are important to humans for nutritional, cultural, and economic reasons. Polar bearsUrsus maritimusare threatened by sea‐ice loss and represent a subsistence resource for Indigenous people. We applied a novel population modeling‐management framework that is based on species life history and accounts for habitat loss to evaluate subsistence harvest for the Chukchi Sea (CS) polar bear subpopulation. Harvest strategies followed a state‐dependent approach under which new data were used to update the harvest on a predetermined management interval. We found that a harvest strategy with a starting total harvest rate of 2.7% (˜85 bears/yr at current abundance), a 2:1 male‐to‐female ratio, and a 10‐yr management interval would likely maintain subpopulation abundance above maximum net productivity level for the next 35 yr (approximately three polar bear generations), our primary criterion for sustainability. Plausible bounds on starting total harvest rate were 1.7–3.9%, where the range reflects uncertainty due to sampling variation, environmental variation, model selection, and differing levels of risk tolerance. The risk of undesired demographic outcomes (e.g., overharvest) was positively related to harvest rate, management interval, and projected declines in environmental carrying capacity; and negatively related to precision in population data. Results reflect several lines of evidence that the CS subpopulation has been productive in recent years, although it is uncertain how long this will last as sea‐ice loss continues. Our methods provide a template for balancing trade‐offs among protection, use, research investment, and other factors. Demographic risk assessment and state‐dependent management will become increasingly important for harvested species, like polar bears, that exhibit spatiotemporal variation in their response to climate change.}, journal={Ecological Applications}, author={Regehr, Eric V. and Runge, Michael C. and Duyke, Andrew Von and Wilson, Ryan R. and Polasek, Lori and Rode, Karyn D. and Hostetter, Nathan J. and Converse, Sarah J.}, year={2021}, month={Dec} }
 @article{amburgey_adams_gardner_hostetter_siers_mcclintock_converse_2021, title={Evaluation of camera trap‐based abundance estimators for unmarked populations}, url={https://doi.org/10.1002/eap.2410}, DOI={10.1002/eap.2410}, abstractNote={AbstractEstimates of species abundance are critical to understand population processes and to assess and select management actions. However, capturing and marking individuals for abundance estimation, while providing robust information, can be economically and logistically prohibitive, particularly for species with cryptic behavior. Camera traps can be used to collect data at temporal and spatial scales necessary for estimating abundance, but the use of camera traps comes with limitations when target species are not uniquely identifiable (i.e., “unmarked”). Abundance estimation is particularly useful in the management of invasive species, with herpetofauna being recognized as some of the most pervasive and detrimental invasive vertebrate species. However, the use of camera traps for these taxa presents additional challenges with relevancy across multiple taxa. It is often necessary to use lures to attract animals in order to obtain sufficient observations, yet lure attraction can influence species’ landscape use and potentially induce bias in abundance estimators. We investigated these challenges and assessed the feasibility of obtaining reliable abundance estimates using camera‐trapping data on a population of invasive brown treesnakes (Boiga irregularis) in Guam. Data were collected using camera traps in an enclosed area where snakes were subject to high‐intensity capture–recapture effort, resulting in presumed abundance of 116 snakes (density = 23/ha). We then applied spatial count, random encounter and staying time, space to event, and instantaneous sampling estimators to photo‐capture data to estimate abundance and compared estimates to our presumed abundance. We found that all estimators for unmarked populations performed poorly, with inaccurate or imprecise abundance estimates that limit their usefulness for management in this system. We further investigated the sensitivity of these estimators to the use of lures (i.e., violating the assumption that animal behavior is unchanged by sampling) and camera density in a simulation study. Increasing the effective distances of a lure (i.e., lure attraction) and camera density both resulted in biased abundance estimates. Each estimator rarely recovered truth or suffered from convergence issues. Our results indicate that, when limited to unmarked estimators and the use of lures, camera traps alone are unlikely to produce abundance estimates with utility for brown treesnake management.}, journal={Ecological Applications}, author={Amburgey, S. M. and Adams, A. A. Yackel and Gardner, B. and Hostetter, N. J. and Siers, S. R. and McClintock, B. T. and Converse, S. J.}, year={2021}, month={Oct} }
 @article{payton_evans_hostetter_roby_cramer_collis_2020, title={Measuring the Additive Effects of Predation on Prey Survival Across Spatial Scales}, volume={101}, url={https://doi.org/10.1002/bes2.1756}, DOI={10.1002/bes2.1756}, abstractNote={In the Columbia River, USA, Caspian terns (Hydroprogne caspia) prey upon endangered steelhead trout (Oncorhynchus mykiss). We used a mark–recapture–recovery dataset to jointly estimate tern predation and steelhead survival to investigate to what degree predation was an additive versus compensatory source of fish mortality. Results provide novel evidence that tern predation was a super additive source of fish mortality during the juvenile life stage and a partially additive source of mortality to the adult life stage, despite predation occurring only during the juvenile life stage. Estimated levels of compensation have important implications for predator management actions aimed at increasing the survival of steelhead. These photographs illustrate the article “Measuring the additive effects of predation on prey survival across spatial scales” by Quinn Payton, Allen F. Evans, Nathan J. Hostetter, Daniel D. Roby, Brad Cramer, and Ken Collis published in Ecological Applications. https://doi.org/10.1002/eap.2193}, number={4}, journal={The Bulletin of the Ecological Society of America}, publisher={Wiley}, author={Payton, Quinn and Evans, Allen F. and Hostetter, Nathan J. and Roby, Daniel D. and Cramer, Brad and Collis, Ken}, year={2020}, month={Oct} }
 @article{payton_evans_hostetter_roby_cramer_collis_2020, title={Measuring the additive effects of predation on prey survival across spatial scales}, volume={30}, url={https://doi.org/10.1002/eap.2193}, DOI={10.1002/eap.2193}, abstractNote={AbstractThe degree to which predation is an additive vs. compensatory source of mortality is fundamental to understanding the effects of predation on prey populations and evaluating the efficacy of predator management actions. In the Columbia River basin, USA, predation by Caspian Terns (Hydroprogne caspia) on U.S. Endangered Species Act (ESA)‐listed juvenile salmonids (smolts; Oncorhynchus spp.) has led to predator management actions to reduce predation; however, the assumption that reduced predation translates into greater salmonid survival, either within the life stage where predation occurs or across their lifetime, has remained untested. To address this critical uncertainty, we analyzed a long‐term (2008–2018) mark–recapture–recovery data set of ESA‐listed steelhead trout (O. mykiss) that were tagged (n = 78,409) and subsequently exposed to predation during smolt out‐migration through multiple river reaches (spatial scales), jointly estimating weekly probabilities of steelhead survival, mortality due to bird predation, and mortality due to other causes. This concurrent estimation across time‐stratified cohorts allowed for the direct measurement of the strength, magnitude, and direction of relationships between survival and Caspian Tern predation. Estimates of Tern predation on steelhead were substantial in most years, with cumulative annual estimates ranging from 0.075 (95% creditable interval = 0.058–0.099) to 0.375 (0.290–0.461). Increases in Tern predation probabilities were associated with statistically significant decreases in steelhead survival probabilities in all evaluated years and salmonid life stages (smolt out‐migration and smolt‐to‐adult returns). Results provide novel evidence that predation by Caspian Terns may have been a super‐additive source of mortality during the smolt life stage and a partially additive source of mortality to the adult life stage. Annual estimates of the difference between observed survival and baseline survival (i.e., in the absence of Tern predation) ranged from 0.052 (0.017–0.103) to 0.314 (0.172–0.459) during the steelhead smolt life stage and from 0.011 (0.001–0.029) to 0.049 (0.025–0.078) to the adult life stage. The estimated levels of compensation have important implications for predator management actions aimed at increasing the survival of endangered salmonids, and the modeling approach developed herein provides a framework to directly quantify the impacts of source‐specific mortality factors on prey populations.}, number={8}, journal={Ecological Applications}, publisher={Wiley}, author={Payton, Quinn and Evans, Allen F. and Hostetter, Nathan J. and Roby, Daniel D. and Cramer, Brad and Collis, Ken}, year={2020}, month={Dec} }
 @article{hostetter_ryan_grosshuesch_catton_malick‐wahls_smith_gardner_2020, title={Quantifying spatiotemporal occupancy dynamics and multi‐year core‐use areas at a species range boundary}, url={https://doi.org/10.1111/ddi.13066}, DOI={10.1111/ddi.13066}, abstractNote={AbstractAimMany species face large‐scale range contractions and predicted distributional shifts in response to climate change, shifting forest characteristics and anthropogenic disturbances. Canada lynx (Lynx canadensis) are listed as threatened under the U.S. Endangered Species Act and were recently recommended for delisting. Predicted climate‐driven losses in habitat quality and quantity may negatively affect the north‐eastern Minnesota lynx population, one of the six remaining resident populations in the contiguous United States. We develop a large‐scale monitoring protocol and dynamic occupancy modelling framework to identify multi‐year core‐use areas and track spatiotemporal occurrence at the southern periphery of the species range.LocationNorth‐eastern Minnesota lynx geographic unit, Superior National Forest and designated critical habitat, Minnesota, USA.MethodsSpatially and temporally replicated snow track surveys were used to collect lynx detection/non‐detection data across five winters (2014–15 to 2018–19) covering >17,000 km within the 22,100 km2 study area. We used a dynamic occupancy model to evaluate lynx occupancy, persistence, colonization and habitat covariates affecting these processes.ResultsLynx occupancy probabilities displayed high spatial and temporal variability, with grid cell‐specific probabilities ranging from 0.0 in periphery regions to consistently near 1.0 in multi‐year core‐use areas, indicating low turnover rates in those areas. Lynx colonization and persistence increased in areas with more evergreen forest and greater average snowfall, while forest characteristics (3–5 and 10–30 m vegetation density) had mixed relationships with occupancy dynamics. We identified 55 grid cells classified as multi‐year core‐use areas across relatively contiguous regions of high average snowfall and per cent conifer forest.Main conclusionsOur study demonstrates a landscape‐scale multi‐year monitoring programme assessing the effects of habitat characteristics and anthropogenic factors on species distributional changes and landscape‐level occupancy dynamics. Our framework incorporating landscape‐scale resource selection, core‐use area concepts and dynamic occupancy models provides a flexible approach to identify population‐level mechanisms driving species persistence and key areas for conservation protection.}, journal={Diversity and Distributions}, author={Hostetter, Nathan J. and Ryan, Daniel and Grosshuesch, David and Catton, Timothy and Malick‐Wahls, Sarah and Smith, Tamara A. and Gardner, Beth}, editor={Alice, HughesEditor}, year={2020}, month={Jul} }
 @article{hostettere_gardner_sillett_pollock_simons_2019, title={An integrated model decomposing the components of detection probability and abundance in unmarked populations}, volume={10}, ISSN={["2150-8925"]}, url={https://doi.org/10.1002/ecs2.2586}, DOI={10.1002/ecs2.2586}, abstractNote={AbstractAccurate estimates of population abundance are essential to both theoretical and applied ecology. Rarely are all individuals detected during a survey and abundance models often incorporate some form of imperfect detection. Detection probability, however, consists of three components: probability of presence during a survey, probability of availability given presence, and probability of detection given availability and presence. We develop an integrated model to separate these three detection components and provide abundance estimates for the available, present, and superpopulation of individuals. Our framework integrates several common survey methods for unmarked populations: spatially and temporally replicated counts, distance sampling data, and time‐of‐detection data. Simulations indicated relatively unbiased estimates for detection and availability probabilities. Negative bias in estimated superpopulation abundance was present with three temporally replicated surveys, but greatly reduced with six surveys. In a case study of Island Scrub‐Jays (Aphelocoma insularis), posterior modes for presence, availability, and detection probabilities were 0.78, 0.96, and 0.26, respectively, from 10‐min point counts repeated at 97 sites on three occasions, with noticeable differences among available, present, and superpopulation abundance estimates. This generalizable framework integrates common sampling protocols and provides joint inferences on the components of detection probability, spatial and non‐spatial temporary emigration, and abundance in unmarked populations.}, number={3}, journal={ECOSPHERE}, publisher={Wiley}, author={Hostettere, Nathan J. and Gardner, Beth and Sillett, T. Scott and Pollock, Kenneth H. and Simons, Theodore R.}, year={2019}, month={Mar} }
 @article{payton_hostetter_evans_2019, title={Jointly estimating survival and mortality: integrating recapture and recovery data from complex multiple predator systems}, volume={26}, url={https://doi.org/10.1007/s10651-019-00421-8}, DOI={10.1007/s10651-019-00421-8}, number={2}, journal={Environmental and Ecological Statistics}, publisher={Springer Science and Business Media LLC}, author={Payton, Quinn and Hostetter, Nathan J. and Evans, Allen F.}, year={2019}, month={Jun}, pages={107–125} }
 @article{hostetter_royle_2019, title={Movement-assisted localization from acoustic telemetry data}, url={https://doi.org/10.1101/2019.12.31.890962}, DOI={10.1101/2019.12.31.890962}, abstractNote={AbstractBackgroundAcoustic telemetry technologies are being rapidly deployed to study a variety of aquatic taxa including fishes, reptiles, and marine mammals. Large cooperative telemetry networks produce vast quantities of data useful in the study of movement, resource selection and species distribution. Efficient use of acoustic telemetry data requires estimation of acoustic source locations from detections at sensors (i.e. localization). Multiple processes provide information for localization estimation including detection/non-detection data at sensors, information on signal rate, and an underlying movement model describing how individuals move and utilize space. Frequently, however, localization methods only integrate a subset of these processes and do not utilize the full spatial encounter history information available from sensor arrays.MethodsIn this paper we draw analogies between the challenges of acoustic telemetry localization and newly developed methods of spatial capture-recapture (SCR). We develop a framework for localization that integrates explicit sub-models for movement, signal (or cue) rate, and detection probability, based on acoustic telemetry spatial encounter history data. This method, which we call movement-assisted localization, makes efficient use of the full encounter history data available from acoustic sensor arrays, provides localizations with fewer than three detections, and even allows for predictions to be made of the position of an individual when it was not detected at all. We demonstrate these concepts by developing generalizable Bayesian formulations of the SCR movement-assisted localization model to address study-specific challenges common in acoustic telemetry studies.ResultsSimulation studies show that movement-assisted localization models improve point-wise RMSE of localization estimates by > 50% and greatly increased the precision of estimated trajectories compared to localization using only the detection history of a given signal. Additionally, integrating a signal rate sub-model reduced biases in the estimation of movement, signal rate, and detection parameters observed in independent localization models.ConclusionsMovement-assisted localization provides a flexible framework to maximize the use of acoustic telemetry data. Conceptualizing localization within an SCR framework allows extensions to a variety of data collection protocols, improves the efficiency of studies interested in movement, resource selection, and space-use, and provides a unifying framework for modeling acoustic data.}, author={Hostetter, Nathan J. and Royle, J. Andrew}, year={2019}, month={Dec} }
 @article{regehr_hostetter_wilson_rode_martin_converse_2018, title={Integrated Population Modeling Provides the First Empirical Estimates of Vital Rates and Abundance for Polar Bears in the Chukchi Sea}, url={https://doi.org/10.1038/s41598-018-34824-7}, DOI={10.1038/s41598-018-34824-7}, abstractNote={AbstractLarge carnivores are imperiled globally, and characteristics making them vulnerable to extinction (e.g., low densities and expansive ranges) also make it difficult to estimate demographic parameters needed for management. Here we develop an integrated population model to analyze capture-recapture, radiotelemetry, and count data for the Chukchi Sea subpopulation of polar bears (Ursus maritimus), 2008–2016. Our model addressed several challenges in capture-recapture studies for polar bears by including a multievent structure reflecting location and life history states, while accommodating state uncertainty. Female breeding probability was 0.83 (95% credible interval [CRI] = 0.71–0.90), with litter sizes of 2.18 (95% CRI = 1.71–2.82) for age-zero and 1.61 (95% CRI = 1.46–1.80) for age-one cubs. Total adult survival was 0.90 (95% CRI = 0.86–0.92) for females and 0.89 (95% CRI = 0.83–0.93) for males. Spring on-ice densities west of Alaska were 0.0030 bears/km2 (95% CRI = 0.0016–0.0060), similar to 1980s-era density estimates although methodological differences complicate comparison. Abundance of the Chukchi Sea subpopulation, derived by extrapolating density from the study area using a spatially-explicit habitat metric, was 2,937 bears (95% CRI = 1,552–5,944). Our findings are consistent with other lines of evidence suggesting the Chukchi Sea subpopulation has been productive in recent years, although it is uncertain how long this will continue given sea-ice loss due to climate change.}, journal={Scientific Reports}, author={Regehr, Eric V. and Hostetter, Nathan J. and Wilson, Ryan R. and Rode, Karyn D. and Martin, Michelle St. and Converse, Sarah J.}, year={2018}, month={Nov} }
 @article{lloyd_hostetter_jackson_converse_moehrenschlager_2019, title={Optimizing release strategies: a stepping‐stone approach to reintroduction}, url={http://dx.doi.org/10.1111/acv.12448}, DOI={10.1111/acv.12448}, abstractNote={AbstractEvaluation of alternative management strategies enables informed decisions to accelerate species recovery. For reintroductions, post‐release survival to reproductive age is a key parameter influencing population growth. Here, we trial a ‘stepping‐stone’ method to maximize the success of captive‐bred animals when the availability of more suitable wild‐born release candidates is limited. Our approach makes use of relatively safe and established wild populations to prepare captive‐bred individuals for eventual translocation to a final release destination, thus building resilience through establishment of multiple populations over time. We developed a novel multievent model integrating encounter history and biotelemetry data to evaluate reintroduction strategies for the critically endangered Vancouver Island marmot Marmota vancouverensis. We compared post‐release survival of 176 individuals (52 wild‐born, 47 captive‐bred marmots released directly to destinations, and 77 captive‐bred marmots released with a stepping‐stone approach). Survival estimates to prime breeding‐age (PBA), were then used to quantify expected success of potential release strategies. Our analysis indicates that post‐release survival varies by source population and release method, as well as age, season, year, and years since release. Conditional on an objective of maximizing survival to PBA, our results suggest that using wild‐born marmots for translocations as often as possible, and stepping‐stone captive‐bred marmots prior to final release, will result in the best outcomes. There was a 0.86 probability that survival to PBA was greater for captive‐bred marmots released as yearlings using a stepping‐stone approach (survival to PBA mode = 0.13, 95% CRI = 0.05–0.30) than for captive‐bred animals that were directly released to destination sites as one‐year‐olds (survival to PBA mode = 0.04, 95% CRI = 0.01–0.24). Consequently, the stepping‐stone approach yields much higher population establishment or growth potential than previous release strategies that used captive‐bred marmots. Optimizing the combination of release candidates, sites and timing can thereby increase the effectiveness of reintroductions.}, journal={Animal Conservation}, author={Lloyd, Natasha and Hostetter, N. J. and Jackson, C. L. and Converse, S. J. and Moehrenschlager, A.}, year={2019}, month={Apr} }
 @article{felton_hostetter_pollock_simons_2017, title={Managing American Oystercatcher (Haematopus palliatus) Population Growth by Targeting Nesting Season Vital Rates}, volume={40}, ISSN={1524-4695 1938-5390}, url={http://dx.doi.org/10.1675/063.040.sp106}, DOI={10.1675/063.040.sp106}, abstractNote={Abstract. In populations of long-lived species, adult survival typically has a relatively high influence on population growth. From a management perspective, however, adult survival can be difficult to increase in some instances, so other component rates must be considered to reverse population declines. In North Carolina, USA, management to conserve the American Oystercatcher (Haematopus palliatus) targets component vital rates related to fecundity, specifically nest and chick survival. The effectiveness of such a management approach in North Carolina was assessed by creating a three-stage female-based deterministic matrix model. Isoclines were produced from the matrix model to evaluate minimum nest and chick survival rates necessary to reverse population decline, assuming all other vital rates remained stable at mean values. Assuming accurate vital rates, breeding populations within North Carolina appear to be declining. To reverse this decline, combined nest and chick survival would need to increase from 0.14 to ≤ 0.27, a rate that appears to be attainable based on historical estimates. Results are heavily dependent on assumptions of other vital rates, most notably adult survival, revealing the need for accurate estimates of all vital rates to inform management actions. This approach provides valuable insights for evaluating conservation goals for species of concern.}, number={sp1}, journal={Waterbirds}, publisher={Waterbird Society}, author={Felton, Shilo K. and Hostetter, Nathan J. and Pollock, Kenneth H. and Simons, Theodore R.}, year={2017}, month={Feb}, pages={44–54} }
 @article{hostetter_evans_cramer_collis_lyons_roby_2015, title={Quantifying Avian Predation on Fish Populations: Integrating Predator-Specific Deposition Probabilities in Tag Recovery Studies}, volume={144}, ISSN={["1548-8659"]}, DOI={10.1080/00028487.2014.988882}, abstractNote={AbstractAccurate assessment of specific mortality factors is vital to prioritize recovery actions for threatened and endangered species. For decades, tag recovery methods have been used to estimate fish mortality due to avian predation. Predation probabilities derived from fish tag recoveries on piscivorous waterbird colonies typically reflect minimum estimates of predation due to an unknown and unaccounted‐for fraction of tags that are consumed but not deposited on‐colony (i.e., deposition probability). We applied an integrated tag recovery modeling approach in a Bayesian context to estimate predation probabilities that accounted for predator‐specific tag detection and deposition probabilities in a multiple‐predator system. Studies of PIT tag deposition were conducted across three bird species nesting at seven different colonies in the Columbia River basin, USA. Tag deposition probabilities differed significantly among predator species (Caspian terns Hydroprogne caspia: deposition probability = 0.71, 95% credible interval [CRI] = 0.51–0.89; double‐crested cormorants Phalacrocorax auritus: 0.51, 95% CRI = 0.34–0.70; California gulls Larus californicus: 0.15, 95% CRI = 0.11–0.21) but showed little variation across trials within a species or across years. Data from a 6‐year study (2008–2013) of PIT‐tagged juvenile Snake River steelhead Oncorhynchus mykiss (listed as threatened under the Endangered Species Act) indicated that colony‐specific predation probabilities ranged from less than 0.01 to 0.17 and varied by predator species, colony location, and year. Integrating the predator‐specific deposition probabilities increased the predation probabilities by a factor of approximately 1.4 for Caspian terns, 2.0 for double‐crested cormorants, and 6.7 for California gulls compared with traditional minimum predation rate methods, which do not account for deposition probabilities. Results supported previous findings on the high predation impacts from strictly piscivorous waterbirds nesting in the Columbia River estuary (i.e., terns and cormorants), but our findings also revealed greater impacts of a generalist predator species (i.e., California gulls) than were previously documented. Approaches used in this study allow for direct comparisons among multiple fish mortality factors and considerably improve the reliability of tag recovery models for estimating predation probabilities in multiple‐predator systems.Received August 1, 2014; accepted November 11, 2014}, number={2}, journal={TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY}, author={Hostetter, Nathan J. and Evans, Allen F. and Cramer, Bradley M. and Collis, Ken and Lyons, Donald E. and Roby, Daniel D.}, year={2015}, pages={410–422} }
 @article{hostetter_gardner_schweitzer_boettcher_wilke_addison_swilling_pollock_simons_2015, title={Repeated count surveys help standardize multi-agency estimates of American Oystercatcher (Haematopus palliatus) abundance}, volume={117}, ISSN={0010-5422 1938-5129}, url={http://dx.doi.org/10.1650/CONDOR-14-185.1}, DOI={10.1650/condor-14-185.1}, abstractNote={ABSTRACT The extensive breeding range of many shorebird species can make integration of survey data problematic at regional spatial scales. We evaluated the effectiveness of standardized repeated count surveys coordinated across 8 agencies to estimate the abundance of American Oystercatcher (Haematopus palliatus) breeding pairs in the southeastern United States. Breeding season surveys were conducted across coastal North Carolina (90 plots) and the Eastern Shore of Virginia (3 plots). Plots were visited on 1–5 occasions during April–June 2013. N-mixture models were used to estimate abundance and detection probability in relation to survey date, tide stage, plot size, and plot location (coastal bay vs. barrier island). The estimated abundance of oystercatchers in the surveyed area was 1,048 individuals (95% credible interval: 851–1,408) and 470 pairs (384–637), substantially higher than estimates that did not account for detection probability (maximum counts of 674 individuals and 316 pairs). Detection probability was influenced by a quadratic function of survey date, and increased from mid-April (~0.60) to mid-May (~0.80), then remained relatively constant through June. Detection probability was also higher during high tide than during low, rising, or falling tides. Abundance estimates from N-mixture models were validated at 13 plots by exhaustive productivity studies (2–5 surveys wk−1). Intensive productivity studies identified 78 breeding pairs across 13 productivity plots while the N-mixture model abundance estimate was 74 pairs (62–119) using only 1–5 replicated surveys season−1. Our results indicate that standardized replicated count surveys coordinated across multiple agencies and conducted during a relatively short time window (closure assumption) provide tremendous potential to meet both agency-level (e.g., state) and regional-level (e.g., flyway) objectives in large-scale shorebird monitoring programs.}, number={3}, journal={The Condor}, publisher={Oxford University Press (OUP)}, author={Hostetter, Nathan J. and Gardner, Beth and Schweitzer, Sara H. and Boettcher, Ruth and Wilke, Alexandra L. and Addison, Lindsay and Swilling, William R. and Pollock, Kenneth H. and Simons, Theodore R.}, year={2015}, month={Aug}, pages={354–363} }
 @article{hostetter_evans_loge_o'connor_cramer_fryer_collis_2015, title={The Influence of Individual Fish Characteristics on Survival and Detection: Similarities across Two Salmonid Species}, volume={35}, ISSN={["1548-8675"]}, DOI={10.1080/02755947.2015.1077176}, abstractNote={AbstractTrait‐selective mortality is of considerable management and conservation interest, especially when trends are similar across multiple species of conservation concern. In the Columbia River basin, thousands of juvenile Pacific salmonids Oncorhynchus spp. are collected each year and are tagged at juvenile bypass system (JBS) facilities located at hydroelectric dams, thus allowing the tracking of population‐level performance metrics (e.g., juvenile survival and juvenile‐to‐adult survival). Several studies have suggested that juvenile salmonid survival is both size dependent and condition dependent, but little is known about trait‐selective collection at JBS facilities. Trait‐selective collection (e.g., length‐based or condition‐based selectivity) is particularly important, as inferences to population‐level performance metrics may be biased if both the survival and collection processes are influenced by similar characteristics. We used a capture–mark–recapture study to investigate length‐ and condition‐selective survival and detection probabilities for two salmonid species in the Columbia River basin. In 2014, juvenile steelhead O. mykiss (n = 11,201) and yearling Chinook Salmon O. tshawytscha (n = 7,943) were PIT‐tagged, measured (FL), examined for external condition characteristics (descaling, body injuries, fin damage, or disease symptoms), and released into the Lower Granite Dam JBS facility on the Snake River to continue seaward migration. Results indicated similar trends in both length‐ and condition‐selective juvenile survival and detection probabilities. For both species, survival probability was higher for longer, nondegraded individuals (those without descaling, body injuries, or fin damage). Trends in detection probability were also consistent across species: shorter, degraded individuals were more likely to be detected at downstream JBS facilities than longer, healthier individuals. These results suggest that similar characteristics (FL and external condition) affect survival and detection processes for PIT‐tagged steelhead and yearling Chinook Salmon and that JBS facilities may selectively collect smaller, degraded individuals with lower probabilities of survival. The consistency in trait‐selective survival and detection results has important management implications for several species of conservation concern.Received February 3, 2015; accepted July 20, 2015}, number={5}, journal={NORTH AMERICAN JOURNAL OF FISHERIES MANAGEMENT}, author={Hostetter, Nathan J. and Evans, Allen F. and Loge, Frank J. and O'Connor, Rolland R. and Cramer, Bradley M. and Fryer, Derek and Collis, Ken}, year={2015}, pages={1034–1045} }
 @article{rivera_zegarra_puente-rolón_arocho-hernandez_hostetter_collazo_bell_2024, title={Multiple records of the introduced parthenogenetic Smooth-scaled Tegulet, Gymnophthalmus underwoodi Grant 1958, in Puerto Rico}, volume={31}, url={https://journals.ku.edu/reptilesandamphibians/article/view/21466}, DOI={10.17161/randa.v16i1}, number={1}, journal={Reptiles & Amphibians}, author={Rivera, Danielle and Zegarra, Jan and Puente-Rolón, Alberto R. and Arocho-Hernandez, Nahira and Hostetter, Nathan and Collazo, Jaime and Bell, Rayna}, year={2024}, month={Mar}, pages={e21466} }