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At least 397 records · Page 22Linked to original sources
USGS2019

Moving at the speed of flight: Dabbling duck-movement rates and the relationship with electronic tracking interval

Context. Effective wildlife management requires information on habitat and resource needs, which can be estimated with movement information and modelling energetics. One necessary component of avian models is flight speeds at multiple temporal scales. Technology has limited the ability to accurately assess flight speeds, leading to estimates of questionable accuracy, many of which have not been updated in almost a century. Aims. We aimed to update flight speeds of ducks, and differentiate between migratory and non-migratory flight speeds, a detail that was unclear in previous estimates. We also analysed the difference in speeds of migratory and non-migratory flights, and quantified how data collected at different temporal intervals affected estimates of flight speed. Methods. We tracked six California dabbling duck species with high spatio-temporal resolution GPS–GSM transmitters, calculated speeds of different flight types, and modelled how estimates varied by flight and data interval (30 min to 6 h). Key results. Median migratory speeds were faster (but non-significant) for the larger mallard (Anas platyrhynchos; 82.5 km h–1), northern pintail (Anas acuta; 79.0 km h–1) and gadwall (Mareca strepera; 70.6 km h–1), than the smaller-bodied northern shoveler (Spatula clypeata; 65.7 km h–1), cinnamon teal (Spatula cyanoptera; 63.5 km h–1) and American wigeon (Mareca Americana; 52 km h–1). Migratory flights were faster than non-migratory flights for all species and speeds were consistently slower with an increasing data interval. Implications. The need to balance time and energy requirements may drive different speeds for migratory and non-migratory flights. Lower speeds at longer intervals are likely to be due to a greater proportion of ‘loafing’ time included in flighted segments, demonstrating that data acquired at different intervals provide a means to evaluate and estimate behaviours that influence speed estimation. Shorter-interval data should be the most accurate, but longer-interval data may be easier to collect over lengthier timeframes, so it may be expedient to trade-off a degree of accuracy in broad-scale studies for the larger dataset. Our updated flight speeds for dabbling duck species can be used to parameterise and validate energetics models, guide management decisions regarding optimal habitat distribution, and, ultimately, improve conservation management of wetlands for waterfowl.

Wildlife Research↗
USGS2020

Sources and dynamics of international funding for waterfowl conservation in the Prairie Pothole Region of North America

Context: Funding for habitat-management programs to maintain population viability is critical for conservation of migratory species; however, such financial resources are limited and can vary greatly over time. The Prairie Pothole Region (PPR) of North America is an excellent system for examining spatiotemporal patterns of funding for waterfowl conservation, because this transboundary region is crucial for reproduction and migration of many duck species. Aims: We examine large-scale spatiotemporal variation in funding for waterfowl habitat conservation in the PPR during 2007–2016. Specifically, we quantify major sources of funding and how funds were directed towards particular geographies within Canada and the USA. We further examine how sources and magnitude of funding changed over time and in relation to numbers of hunters. Methods: We assembled data from multiple sources to quantify funding (in US$, 2016 values) from (1) USA states and non-government organisations (NGOs), (2) Canadian government and NGOs, and (3) major USA-based federal funding sources to the Canadian and US portions of the PPR between 2007 and 2016. We fit linear regressions to examine spatiotemporal variation in funding and in numbers of active waterfowl hunters in the USA. Key results: Whereas annual funding for the Canadian portion was comparatively stable throughout the 10 years (range: US$25–41 million), funding for the US portion was dynamic and increased between the first (range: US$36–48 million) and second (range: US$43–117 million) 5-year intervals, despite concurrent declines in the number of active waterfowl hunters in the USA. Conclusions: We discovered contrasting trends and dynamics in multiple streams of funding for habitat conservation on each side of the border bisecting the PPR. These findings and approaches warrant closer attention by wildlife professionals. Work is needed to analyse past and future funding for habitat conservation, which can then be used to refine plans for maintaining or recovering populations of migratory species. Implications: Although funding for waterfowl habitat conservation in the PPR increased over the past decade, trends were inconsistent among subregions and uncertain for some major funding sources. Better understanding of the complexities in funding will help inform more efficient long-term planning efforts for conservation of waterfowl and other migratory species.

Wildlife Research↗
USGS2021

Olfactory lures in predator control do not increase predation risk to birds in areas of conservation concern

Context: Lethal control of predators is often undertaken to protect species of conservation concern. Traps are frequently baited to increase capture efficacy, but baited traps can potentially increase predation risk by attracting predators to protected areas. This is especially important if targeted predators can escape capture due to low trap success. Snake traps using live mouse lures may be beneficial if traps effectively remove snakes in the presence of birds and do not attract additional snakes to the area. Aims: The present study evaluated whether mouse-lure traps in areas occupied by birds (simulated by deploying bird-lure traps) could influence predation risk from an invasive snake on Guam. Methods: Snake traps were used, with Japanese quail ( Coturnix japonica ) as a proxy for predation risk, to assess if an adjacent trap with a mouse ( Mus musculus ) would attract brown treesnakes ( Boiga irregularis ) to a focal area and increase contact between an invasive snake and avian prey. Catch per unit effort (CPUE) at stations containing either a bird-lure trap, mouse-lure trap or pair of traps (i.e. one bird-lure and one mouse-lure trap) was evaluated. Key results: Bird-lure traps paired with mouse-lure traps did not differ in CPUE from isolated bird-lure traps. At paired stations, CPUE of snakes in mouse-lure traps was 2.3× higher than bird-lure traps, suggesting mouse lures were capable of drawing snakes away from avian prey. Bird-lure traps at paired stations experienced a decay in captures over time, whereas CPUE for isolated bird-lure traps increased after 9 weeks and exceeded mouse-lure traps after 7 weeks. Conclusions: Mouse lures did not increase the risk of snakes being captured in bird-lure traps. Instead, mouse-lure traps may have locally suppressed snakes, whereas stations without mouse-lure traps still had snakes in the focal area, putting avian prey at greater risk. However, snakes caught with bird lures tended to be larger and in better body condition, suggesting preference for avian prey over mammalian prey in larger snakes. Implications: Strategic placement of olfactory traps within areas of conservation concern may be beneficial for protecting birds of conservation concern from an invasive snake predator.

Wildlife Research↗
USGS2021

Birds not in flight: Using camera traps to observe ground use of birds at a wind-energy facility

Context: Camera trapping is increasingly used to collect information on wildlife occurrence and behaviour remotely. Not only does the technique provide insights into habitat use by species of interest, it also gathers information on non-target species. Aims: We implemented ground-based camera trapping to investigate the behaviours of ground-dwelling birds, a technique that has largely been unutilised for studying birds, especially in wind-energy facilities. Methods: We used camera traps to monitor activities of Agassiz’s desert tortoises ( Gopherus agassizii ) at their self-constructed burrows in a wind-energy facility near Palm Springs, California, USA. While doing so, we collected data on numerous burrow commensals, including birds. Key results: Monitoring from late spring to mid-autumn in one year showed regular use of tortoise burrows and the immediate area by 12 species of birds, especially passerines. The most abundant species, as indicated by the number of photographs, but not necessarily individuals, was the rock wren ( Salpinctes obsoletus ), with a total of 1499 events. Birds appeared to use the interior or proximate vicinity of burrows for gathering nesting material, displaying, feeding, dust bathing and other activities. Of the bird species observed, 10 are known to be occasional casualties of turbine-blade strikes. The minimum known-age of a burrow had a positive relationship with bird counts. Conclusions: Using camera traps focused at ground level can be a useful tool in avian conservation efforts because it is an effective technique for measuring bird presence, activity and behaviour in altered habitats such as wind farms, especially for those species that are low flyers or ground dwellers. Implications: Acquiring data over the long term by using ground-based monitoring with camera traps could add to our understanding of avian behaviour and habitat use in relation to wind-energy infrastructure and operations, and help determine the vulnerability of avifauna that utilise the area.

California↗
USGS2022

Deltamethrin reduces survival of non-target small mammals

Context: Vector-borne diseases have caused global pandemics and were responsible for more human deaths than all other causes combined in prior centuries. In the past 60 years, prevention and control programs have helped reduce human mortality from vector-borne diseases, but impacts of those control programs on wildlife populations are not well documented. Insecticides are used to reduce vector-borne diseases in several critically endangered animal populations. Although insecticides are often effective at controlling targeted vectors, their effects on non-target species have rarely been examined. Aims: To evaluate the impact of deltamethrin (an insecticide) on sympatric non-target species in areas affected by sylvatic plague, a lethal flea-borne zoonosis. Methods: We compared flea control and the effect of deltamethrin application on survival of non-target small mammals ( Peromyscus maniculatus , Chaetodipus hispidus , Microtus spp., and Reithrodontomys megalotis ) at three study locations in South Dakota, Colorado, and Idaho, USA. Key results: Deltamethrin treatments were more effective in reducing fleas on P. maniculatus and Microtus spp. than C. hispidus . Following burrow, nest, and bait-station applications of deltamethrin dust, apparent small mammal survival was greater for non-treatment animals than for flea-reduction animals. However, the magnitude of the difference between treated and non-treated animals differed among host species, study location, time interval, and treatment application method. Conclusions: Our results suggest that considering the impact of deltamethrin on co-occurring non-target species before widespread application in future insecticide applications is warranted. Implications: Insecticide application methods warrant consideration when designing plague management actions.

Colorado, Idaho, South Dakota↗
USGS2022

Can non-invasive methods replace radiocollar-based winter counts in a 50-year wolf study? Lessons learned from a three-winter trial

Context: Monitoring low-density, elusive predators such as grey wolves ( Canis lupus ) has often been undertaken via live-capture and radio-collaring. Recent advances in non-invasive methods suggest live-captures may not be necessary for adequate monitoring. Further, non-invasive methods are considered best practice when possible. Aims: I evaluated whether a suite of non-invasive methods could replace aerial radiotelemetry to census resident pack wolves. Methods: I employed aerial snow-tracking, ground snow-tracking, camera-trapping, non-invasive genetic surveys, and community-scientist reports during three winters (2019–2021) in north-eastern Minnesota, USA to census pack wolves in a 2060 km 2 area. I attempted to enumerate individual pack sizes as has been historically undertaken to compile the census. Traditional aerial radiotelemetry methods were also conducted for comparison. Key results: Ground snow-tracking and camera-trapping provided the most similar information to radiotelemetry for determining pack counts and territory information, and, in some cases, documented higher pack counts than those obtained by aerial radiotelemetry. Radiotelemetry was the best method for determining pack territories, but was limited to radioed packs. A staggered application of both approaches resulted in increased precision and additional pack-level information without greatly increasing overall field effort. Non-invasive methods allowed trapping for radio-collaring to be reduced to every other year (a 50% reduction), but depending on trapping success, survival of animals, and radio-collar battery life, might even be reduced to every third year. Conclusions: In this 3-year trial, non-invasive methods were not sufficient to completely replace radio-collaring. Nevertheless, non-invasive methods allowed for a 50% reduction in trapping, increased the annual wolf-count precision, and increased community involvement. Anticipated technological improvements in non-invasive methods should reduce some issues encountered – but others will likely persist, in part, because of the fundamental nature of non-invasive methods. Implications: Less reliance on captures, enhanced pack information, and increased public involvement are all successful outcomes of this 3-year trial of non-invasive methods for monitoring wolf populations. Non-invasive methods continue to broaden and improve technologically, and information from trials such as this will help guide others as they increasingly implement non-invasive methods as partial or complete replacements for traditional capture-based methods.

Wildlife Research↗
USGS2022

Hot, wet and rare: Modelling the occupancy dynamics of the narrowly distributed Dixie Valley toad

Context: Small population sizes and no possibility of metapopulation rescue put narrowly distributed endemic species under elevated risk of extinction from anthropogenic change. Desert spring wetlands host many endemic species that require aquatic habitat and are isolated by the surrounding xeric terrestrial habitat. Aims: We sought to model the occupancy dynamics of the Dixie Valley toad ( Anaxyrus williamsi ), a recently described species endemic to a small desert spring wetland complex in Nevada, USA. Methods: We divided the species’ range into 20 m × 20 m cells and surveyed for Dixie Valley toads at 60 cells during six primary periods from 2018 to 2021, following an occupancy study design. We analysed our survey data by using a multi-state dynamic occupancy model to estimate the probability of adult occurrence, colonisation, site survival, and larval occurrence and the relationship of each to environmental covariates. Key results: The detection probabilities of adult and larval toads were affected by survey length and time of day. Adult Dixie Valley toads were widely distributed, with detections in 75% of surveyed cells at some point during the 3-year study, whereas larvae were observed only in 20% of cells during the study. Dixie Valley toad larvae were more likely to occur in cells far from spring heads with a high coverage of surface water, low emergent vegetation cover, and water temperatures between 20°C and 28°C. Adult toads were more likely to occur in cells with a greater coverage of surface water and water depth >10 cm. Cells with more emergent vegetation cover and surface water were more likely to be colonised by adult toads. Conclusions: Our results showed that Dixie Valley toads are highly dependent on surface water in both spring and autumn. Adults and larvae require different environmental conditions, with larvae occurring farther from spring heads and in fewer cells. Implications: Disturbances to the hydrology of the desert spring wetlands in Dixie Valley could threaten the persistence of this narrowly distributed toad.

Wildlife Research↗
USGS2022

Nest remains are insufficient to identify predators of waterfowl nests

Context: Nest predation is a leading cause of nest failure for most ground-nesting birds. Methods that allow for accurate classification of fate and identification of predators are important for understanding productivity and conservation strategies. Past studies have used a visual inspection of nest remains to determine nest fate and predict predator identity. Most formal assessments of these methods have addressed small-bodied birds nesting in trees or shrubs, and have revealed that use of evidence at nests can be relatively accurate for determining nest fate but may lead to incorrect conclusions regarding predator identity. However, few have tested the latter hypothesis for larger ground-nesting birds with precocial young. Aim: We aimed to evaluate a classification system developed for determining nest fate and identifying predators of waterfowl nests, at both the scale of individual nests and across the study area. Methods: From 2016 to 2020, we located 989 blue-winged teal ( Spatula discors ), mallard ( Anas platyrhynchos ) and gadwall ( Mareca strepera ) nests in central North Dakota. We placed cameras at a subset of 249 nests and recorded evidence of nest remains at depredated nests. Key results: The most common predators were American badgers ( Taxidea taxus ), followed by striped skunks ( Mephitis mephitis ), raccoons ( Procyon lotor ) and red foxes ( Vulpes vulpes ). Using evidence of nest remains, we determined nest fates with high accuracy (98.0%). However, evidence of nest remains was only sufficient for identifying predators at 50% of nests, and the classification system was correct only 69.7% of the time. The predicted proportion of predators across the study area differed between the classification system and our video evidence as well. Conclusions: The accuracy of predator identifications based upon the classification system that we evaluated was not supported at any scale. Implications: Our results suggest that evidence of nest remains can be used to determine nest fate for large-bodied precocial, ground-nesting birds, but accurate identification of nest predators will require alternative methods such as nest cameras.

Wildlife Research↗
USGS2023

Movement ecology of adult and juvenile spotted turtles (Clemmys guttata) in a seasonally dynamic environment

Context Understanding the temporal and spatial scales at which wildlife move is vital for conservation and management. This is especially important for semi-aquatic species that make frequent inter-wetland movements to fulfil life-history requirements. Aims We aimed to investigate the drivers of movement and space-use of the imperilled spotted turtle ( Clemmys guttata ), a seasonal wetland specialist, in three large, isolated wetland complexes in Virginia, USA. Methods We used VHF radio-transmitters to radio-locate adult and juvenile turtles, and estimated movement and space-use during their active and aestivation seasons (March–August). We then used generalised linear mixed models to examine how movement and space-use varied, based on intrinsic turtle characteristics and extrinsic wetland and climatic factors. Key results We show that, on average, individual spotted turtles used five wetlands per year (range 3–13), and that their inter-wetland movement and movement distance varied seasonally in accordance with wetland availability and breeding phenology. Spotted turtle movement and space-use was influenced by the arrangement and size of the wetland complexes, with turtles moving further and occupying larger home-ranges as size and distance between wetlands increased. Inter-wetland movement was not influenced by intrinsic turtle effects but larger adult turtles moved further, used more wetlands, and had larger home-ranges than smaller turtles. Conclusions Turtle responses to variation in season and wetland configuration highlight the need for complex and dynamic landscapes required to sustain this species. Implications This study has important conservation implications showing that spotted turtles rely on a large number of diverse wetlands, as well as upland habitat, to fulfil their resource needs – and that these habitat associations vary seasonally. Results from our study can aid the understanding of spatial and temporal variation in patch characteristics (e.g. quality and extent) and inter-patch movement by organisms, which is critical for the conservation and management of semi-aquatic species and other organisms that occupy patchy habitat complexes.

Wildlife Research↗
USGS2023

Managing conflict between nesting common terns and herring gulls

Context: Due to the frequent depredation of eggs and chicks by herring gulls ( Larus argentatus ), numerous approaches to reduce their impact on tern colonies have been tested by wildlife managers. Previous studies have shown that the use of overhead lines presents a promising method to prevent gull nesting in tern colonies, but little work has evaluated if this approach is suitable for excluding both nesting and non-nesting gulls. Aims: The goal of this study was to explore the efficacy of a preventative approach, overhead lines, versus a more widely practiced lethal approach, shooting and trapping. Specifically, we aimed to determine if methods differ in their abilities to deter both gull nesting and presence within treatment areas and identify impacts on common tern ( Sterna hirundo ) nesting within treatment areas. Methods: We applied separate management strategies to two common tern colonies. In one colony, we removed herring gulls via shooting followed by trapping and nest removal, and in the other colony, we erected overhead lines with subsequent trapping at nests established in the treatment area. Key results: Gulls appeared to adapt quickly to shooting efforts, limiting efficacy and resulting in no significant change in abundance from pre-treatment levels ( P = 0.981). However, gull use of both the colony and surrounding brush declined significantly ( P < 0.001) following trapping and nest removal. Meanwhile, the number of gulls in the colony area declined from a pre-treatment average of 56 to only six, following the erection of overhead lines ( P < 0.001). Although six gull nests were established within the treatment area (overhead lines), they were not replaced once the parents were trapped and nests destroyed. Conclusions: Tern nesting appeared to be unaffected by any of the implemented management activities. Our data suggest that overhead lines may present an alternative to lethal control when seeking to minimise the impacts of gulls on tern colonies. Implications: The data presented in this manuscript can be used to guide managers in selecting actions to reduce conflict between gulls and breeding common terns. By using data-informed practices, managers can select the method best suited for their specific needs and priorities.

Wildlife Research↗
USGS2024

Mesocarnivores in residential yards: Influence of yard features on the occupancy, relative abundance, and overlap of coyotes, grey fox, and red fox

Context As conversion of natural areas to human development continues, there is a lack of information about how developed areas can sustainably support wildlife. While large predators are often extirpated from areas of human development, some medium-bodied mammalian predators (hereafter, mesocarnivores) have adapted to co-exist in human-dominated areas. Aims How human-dominated areas such as residential yards are used by mesocarnivores is not well understood. Our study aimed to identify yard and landscape features that influence occupancy, relative abundance and spatial-temporal overlap of three widespread mesocarnivores, namely, coyote ( Canis latrans ), grey fox ( Urocyon cineroargenteus ) and red fox ( Vulpes vulpes ). Methods Over the summers of 2021 and 2022, we deployed camera-traps in 46 and 96 residential yards, spanning from low-density rural areas (<1 home per km 2 ) to more urban areas (589 homes per km 2 ) in north-western Arkansas, USA. Key results We found that mesocarnivore occupancy was marginally influenced by yard-level features as opposed to landscape composition. Fences reduced the occupancy probability of coyotes, although they were positively associated with the total area of potential shelter sites in a yard. We found that relative abundance of grey fox was highest in yards with poultry, highlighting a likely source of conflict with homeowners. We found that all three species were primarily nocturnal and activity overlap between the species pairs was high. Conclusions Thus, these species may be using spatio-temporal partitioning to avoid antagonistic encounters and our data supported this, with few examples of species occurring in the same yards during the same 24-h period. Implications As the number of residential yards continues to grow, our results suggested that there are ways in which our yards can provide resources to mesocarnivores and that homeowners also have agency to mitigate overlap with mesocarnivores through management of their yard features.

Arkansas, Missouri↗
USGS2025

Behavioral plasticity in detection height of an invasive, arboreal snake based on size, condition, and prey

Context Animals may adjust their behavior in predictable ways to balance tradeoffs between resource acquisition and survival or fecundity. Microhabitat selection based on individual traits or environmental conditions is one measure of risk–reward tradeoffs by individuals. Aims We used data from observational and manipulative studies to investigate whether an arboreal snake (brown treesnake, Boiga irregularis ) had context-dependent behavior based on the relationship between estimated prey availability, body condition, size, and detection height (microhabitat use) in two Mariana Islands. Methods We used observational data collected in four study sites and data from a manipulative study that we collected over a 5-year period. The observational data focused on four sites with different counts of three prey types, including lizards, birds, and small mammals. During the manipulative study we removed snakes, which resulted in increased prey counts over time. Using these two approaches, we tested whether prey counts predicted body condition and then evaluated how prey counts, snake size, and snake condition interactively predicted the detection height of captured individuals. Key results We found that body condition was greater at sites or in years with greater prey counts across both the observational and manipulative studies. We also found that snakes displayed differential microhabitat use based on both their condition and size. Larger snakes tended to be detected lower than smaller snakes, but only at sites or during years with few bird or small mammal counts. Snakes at sites with greater mammal and bird counts had a positive relationship between size and detection height. Snakes with greater condition scores tended to be detected higher irrespective of size, but this was also dependent on prey counts. At sites with low bird counts, snakes that were in better condition tended to be closer to the ground. Conclusions Brown treesnakes modified microhabitat use based on their condition, size, and the number or type of prey available. Our findings were consistent with a hypothesis that they optimized habitat use to secure food resources and maximize survival. Implications Context-dependent behavioral plasticity may be an important consideration for management of reptiles for population control or growth.

Wildlife Research↗
USGS2025

Control of a dominant predator influences the occurrence of a mesocarnivore of conservation concern

Context Interspecific interactions shape ecological communities, influence community dynamics, and drive co-evolution. Despite their ecological significance, predation and competition remain understudied in plains spotted skunks ( Spilogale interrupta ), a species of conservation concern. Clarifying how predator management influences their occurrence is crucial for effective conservation. Aims We investigated how coyote ( Canis latrans ) management affects the occupancy of plains spotted skunks and whether interspecific interactions with domestic cats ( Felis catus ) and striped skunks ( Mephitis mephitis ) influence plains spotted skunk occurrence. Methods We analysed live-trap data from east-central South Dakota collected in spring of 2021 and 2022. The study area encompassed portions of counties that implemented disparate predator management regimes, including one with systematic annual coyote removal and another without. We used single-species occupancy models to estimate detection and occupancy probabilities for plains spotted skunks, domestic cats, and striped skunks, incorporating environmental factors, including the site-specific predator control regime. We then applied conditional two-species occupancy models to test whether cats and striped skunks influenced plains spotted skunk occurrence. Key results Plains spotted skunks had the lowest occupancy, followed by domestic cats, and striped skunks. Our findings showed significant associations between coyote removal and occupancy probabilities for each mesocarnivore species. Plains spotted skunks had higher occupancy in areas where coyotes were annually removed. Spotted skunk occurrence was not conditional on either domestic cat or striped skunk occurrence. Conclusions In our study system, cats appear to pose less predation risk to spotted skunks than do other predators, reducing the likelihood that cats significantly influence spotted skunk occupancy. Defensive behaviours and use of spatial refugia by plains spotted skunks may further mitigate predation risk. In addition, co-evolutionary pressures may have led to trait adaptations that facilitate the independent co-occurrence of plains spotted skunks and striped skunks. Implications Our findings highlighted the ecological consequences of predator management and the importance of considering predator–prey dynamics in conservation and management planning. Strategies aimed at conserving plains spotted skunks should integrate predator control measures while considering broader mesocarnivore community interactions.

South Dakota↗
USGS2020

msocc: Fit and analyse computationally efficient multi‐scale occupancy models in R

Environmental DNA (eDNA) sampling is a promising tool for the detection of rare and cryptic taxa, such as aquatic pathogens, parasites and invasive species. Environmental DNA sampling workflows commonly rely on multi‐stage hierarchical sampling designs that induce complicated dependencies within the data. This complex dependence structure can be intuitively modelled with Bayesian multi‐scale occupancy models. However, current software for such models are computationally demanding, impeding their use. We present an r package, msocc , that implements a data augmentation strategy to fit fully Bayesian, computationally efficient multi‐scale occupancy models. The msocc package allows users to fit multi‐scale occupancy models, to estimate and visualize posterior summaries of site, sample and replicate‐level occupancy, and to compare different models using Bayesian information criterion. Additionally, we provide a supplemental web application that allows users to investigate study design for multi‐scale occupancy models and acts as a graphical user interface to the msocc package. The utility of the msocc package is illustrated on a published dataset and the functions in msocc are compared to the primary Bayesian toolkit for multi‐scale occupancy modelling, eDNAoccupancy , using various computational benchmarks. These benchmarks indicate that msocc is capable of fitting models 50 times faster than eDNAoccupancy . We hope that access to software that efficiently fits, analyses and conducts study design investigations for multi‐scale occupancy models facilitates their implementation by the research and wildlife management communities.

Methods in Ecology and Evolution↗
USGS2014

Reducing bias in survival under non-random temporary emigration

Despite intensive monitoring, temporary emigration from the sampling area can induce bias severe enough for managers to discard life-history parameter estimates toward the terminus of the times series (terminal bias). Under random temporary emigration unbiased parameters can be estimated with CJS models. However, unmodeled Markovian temporary emigration causes bias in parameter estimates and an unobservable state is required to model this type of emigration. The robust design is most flexible when modeling temporary emigration, and partial solutions to mitigate bias have been identified, nonetheless there are conditions were terminal bias prevails. Long-lived species with high adult survival and highly variable non-random temporary emigration present terminal bias in survival estimates, despite being modeled with the robust design and suggested constraints. Because this bias is due to uncertainty about the fate of individuals that are undetected toward the end of the time series, solutions should involve using additional information on survival status or location of these individuals at that time. Using simulation, we evaluated the performance of models that jointly analyze robust design data and an additional source of ancillary data (predictive covariate on temporary emigration, telemetry, dead recovery, or auxiliary resightings) in reducing terminal bias in survival estimates. The auxiliary resighting and predictive covariate models reduced terminal bias the most. Additional telemetry data was effective at reducing terminal bias only when individuals were tracked for a minimum of two years. High adult survival of long-lived species made the joint model with recovery data ineffective at reducing terminal bias because of small-sample bias. The naïve constraint model (last and penultimate temporary emigration parameters made equal), was the least efficient, though still able to reduce terminal bias when compared to an unconstrained model. Joint analysis of several sources of data improved parameter estimates and reduced terminal bias. Efforts to incorporate or acquire such data should be considered by researchers and wildlife managers, especially in the years leading up to status assessments of species of interest. Simulation modeling is a very cost effective method to explore the potential impacts of using different sources of data to produce high quality demographic data to inform management.

Ecological Applications↗
USGS2010

Design and evaluation of a simple signaling device for live traps

Frequent checks of live traps require enormous amounts of labor and add human scents associated with repeated monitoring, which may reduce capture efficiency. To reduce efforts and increase efficiency, we developed a trap-signaling device with long-distance reception, durability in adverse weather, and ease of transport, deployment, and use. Modifications from previous designs include a normally open magnetic switch and a mounting configuration to maximize reception. The system weighed <225 g, was effective ???17.1 km, and failed in <1% of trap-nights. Employing this system, researchers and wildlife managers may reduce the amount of effort checking traps while improving the welfare of trapped animals.

Journal of Wildlife Management↗