Behavioral response of Bornean ungulates, including bearded pigs and sambar deer, to anthropogenic disturbance in Sabah, Malaysia

Global Ecology and Conservation, Journal Year: 2025, Volume and Issue: unknown, P. e03580 - e03580

Published: April 1, 2025

Language: Английский

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A cautionary tale comparing spatial count and partial identity models for estimating densities of threatened and unmarked populations

Global Ecology and Conservation, Journal Year: 2022, Volume and Issue: 38, P. e02268 - e02268

Published: Aug. 18, 2022

Population monitoring is critical to wildlife conservation, but density estimation difficult for wide-ranging, unmarked species inhabiting remote habitats. Furthermore, recent investigations into with camera trap data has revealed models be potentially unreliable, prompting cautious application and continued model development. Two related approaches increasing appeal include spatial count (SC), which infer latent identities from the pattern of detections, partial identity (SPIM), additionally leverage covariates (e.g., sex, antler point count, presence GPS/radio collar). To assess performance models, we applied SC SPIM threatened boreal caribou in Canada, are declining have few rigorous estimates across their broad distribution inform conservation efforts. In particular, focused on two spatially proximate ranges northern Alberta, Canada that differ estimated demographic trends, disturbance histories, abundances predators apparent competitors. Estimates varied over a 4 year period (2016 – 2019), were higher region more stable reported growth rates less anthropogenic (mode estimates: 155 225/1000 km2 vs. 19 96/1000 km2). However, differed by modeling approach had low variable precision, hindering inferences about population status trajectories. Simulations suggest may been biased precise. likely underestimated mistaking detections neighboring individuals as recaptures single individual, although also overestimated inflating assignment probabilities non-existent individuals. Findings highlight need explore how grouping dynamics non-independent movement violate assumptions reduce ability distinguish We advocate investigation accuracy approaches, ecological sampling conditions appropriate different coordination efforts analyses improve inferences.

Language: Английский

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Behavioral “bycatch” from camera trap surveys yields insights on prey responses to human‐mediated predation risk

Ecology and Evolution, Journal Year: 2022, Volume and Issue: 12(7)

Published: July 1, 2022

Human disturbance directly affects animal populations and communities, but indirect effects of on species behaviors are less well understood. For instance, may alter predator activity cause knock-on to predator-sensitive foraging in prey. Camera traps provide an emerging opportunity investigate such disturbance-mediated impacts across multiple scales. We used camera trap data test predictions about behavior three ungulate (caribou

Language: Английский

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Factors affecting Asiatic caracal occupancy and activity in an arid landscape; vegetation, prey and predator presence are key

Global Ecology and Conservation, Journal Year: 2024, Volume and Issue: 53, P. e03002 - e03002

Published: May 25, 2024

Predator populations persisting in desert landscapes may be especially vulnerable to habitat fragmentation and changing climates, but many are chronically understudied at risk of extirpation. The Asiatic subspecies caracal, Caracal caracal schmitzi, inhabit the mountainous western southern Arabian Peninsula, they thought decline across region. In Saudi Arabia, a recent extensive study used camera traps face-to-face questionnaires survey leopards other medium- large-size mammals, simultaneously generating vast bycatch data on presence. We assessed interspecific temporal overlap identified factors that influence occupancy, predict their potential distribution historical range Arabia. From fourteen trap surveys, 497 independent captures caracals were recorded only nine south-western sites. Occupancy modelling showed occurred areas with higher gross primary productivity elevations, as well relative abundance free-roaming cats dogs, striped hyaena, wild prey. Higher abundances large predators decreased detection caracals. Caracals displayed cathemeral activity pattern peaks around sunrise sunset, had high diel wolves. Predictive south mountains stronghold for caracals, low occupancy or extirpation north elsewhere, was highly congruous predictions from false-positive 843 questionnaires. persistence is likely driven by increased vegetation prey associated regions, more frequent human presence potentially increases availability alternative prey, including cats. dry regions particularly climatic changes affecting abundance, have ability adapt benefit limited if conflict can avoided.

Language: Английский

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Lethal wolf control elicits change in moose habitat selection in unexpected ways

Journal of Wildlife Management, Journal Year: 2024, Volume and Issue: 88(7)

Published: July 11, 2024

Abstract Moose ( Alces alces ) and woodland caribou Ranger tarandus are the 2 large prey species for wolves Canis lupus in Nearctic boreal forest North America. Caribou have declined, with widespread anthropogenic disturbance as ultimate cause wolf predation proximal cause. To conserve government of Alberta, Canada initiated a control program to reduce rates on populations contribute population recovery. Predators play an important role shaping structure function ecosystems through top‐down forces. We hypothesized that strongest factors influencing moose occurrences would reflect changes risk before after onset control. weighed evidence competing hypothesis by deploying cameras across highly industrialized landscape Alberta 3 years (2017–2020), capitalizing existing data (2011–2014). created generalized linear models representing hypotheses about response natural features control, examining support each information‐theoretic framework. Prior model containing providing security cover was best‐supported, but this scale‐dependent. After offer increased forage opportunities best‐supported. Unexpectedly, direction effect often opposite predictions, avoiding some thought provide forage. demonstrate lethal predator affects spatial distribution its primary ways we do not fully comprehend, highlighting need better understanding community dynamics following

Language: Английский

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Camera traps reveal that terrestrial predators are pervasive at riverscape cold‐water thermal refuges

Ecology and Evolution, Journal Year: 2023, Volume and Issue: 13(7)

Published: July 1, 2023

Perceived predation risks by terrestrial predators are major ecological forces in aquatic systems, particularly for aggregating fish. Riverscape thermal refuges discrete, localized cold-water patches where fish temporarily aggregate to buffer against heat events. Predation pressures at may decrease the thermoregulatory benefits of refuge use, but quantifying such effects can be challenging and controversial when sampling impose additional stress on We passively monitored predator visitation patterns four Housatonic River, Connecticut, USA, between May 18th September 29th, 2022, with camera traps, a common wildlife monitoring method. Specifically, we (1) assessed diel different categories determined if varied among or prevailing environmental conditions, (2) estimated probability hour day combined across all categories, general refuges. detected least one each day, mean hourly rates (count/h) were highly variable dates. The most supported generalized additive mixed model indicated that (count/h/day) daily river discharge water temperature differential, relationships differed predators. observed 22 separate attempts thermoregulating salmonids predicted any increased from 0.002 0.017 throughout 24 h (

Language: Английский

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Density estimates of unmarked mammals: comparing two models and assumptions across multiple species and years

Canadian Journal of Zoology, Journal Year: 2023, Volume and Issue: 102(3), P. 286 - 297

Published: Oct. 19, 2023

Density estimation is a key goal in ecology, but accurate estimates for unmarked animals remain elusive. Camera trap data can bridge this gap, accuracy, precision, and concordance varies among estimators. We compared from spatial capture–recapture (spatial count (SC)) models, time front of camera (TIFC) four large mammal species boreal Canada. Species differed movement rates, behaviours, sociality—traits related to model assumptions. TIFC densities typically exceeded SC all species. Two- five-fold differences between estimators were common. annually stable moose caribou not white-tailed deer. showed high annual variation some species, sites, years, consistency others. Both models often produced imprecise estimates. Estimates varied DNA- aerial survey-based contend diverge, or implausibly vary, due violations assumptions incurred by animal behaviour. Gregarious pose challenges SC, whereas curious models. Simulations help unravel the role assumption affecting accuracy estimates, field applications across landscapes interpret outcomes estimating density simulated data.

Language: Английский

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Combining camera trap surveys and IUCN range maps to improve knowledge of species distributions

Conservation Biology, Journal Year: 2023, Volume and Issue: 38(3)

Published: Nov. 8, 2023

Abstract Reliable maps of species distributions are fundamental for biodiversity research and conservation. The International Union Conservation Nature (IUCN) range widely recognized as authoritative representations species’ geographic limits, yet they might not always align with actual occurrence data. In recent area habitat (AOH) maps, areas that have been removed from IUCN ranges to reduce commission errors, but their concordance also remains untested. We tested between occurrences recorded in camera trap surveys predicted the AOH 510 medium‐ large‐bodied mammalian 80 sampling areas. Across all areas, cameras detected only 39% expected occur based on maps; 85% mismatches occurred within 200 km edges. Only 4% were by outside ranges. probability was significantly higher smaller‐bodied mammals specialists Neotropics Indomalaya shorter canopy forests. Our findings suggest rarely underrepresent where occur, may more often overrepresent including a be absent, particularly at combining data ground‐based sensors, such traps, provides richer knowledge base conservation mapping planning.

Language: Английский

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Measuring, minimizing, and documenting the impact of onshore seismic surveys

Published: July 24, 2024

Language: Английский

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An overwinter protocol for detecting wolverines and other carnivores at camera traps paired with automated scent dispensers

Ecology and Evolution, Journal Year: 2024, Volume and Issue: 14(5)

Published: May 1, 2024

Abstract Camera traps deployed with olfactory attractants are used to survey rare and elusive carnivores. Study areas deep snowpack rugged terrain present challenges risks field personnel, who traditionally must revisit camera stations regularly refresh attractants. In such locations, alternative overwinter protocols that include a persistent attractant would improve both the safety efficiency of camera‐trap surveys. We protocol for installing automated scent dispensers on trees at above‐average maximum snow depth eliminate need interim service visits enable standardized surveys be conducted throughout year. Our proved effective attracting detecting numerous repeated by wolverines, fishers, other carnivores in two montane regions western contiguous United States. The volume, timing, composition liquid lure released can varied target multiple species interest, dispenser situations where bait rewards may influence behavior and/or pose human concerns.

Language: Английский

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