PanAf20K: A Large Video Dataset for Wild Ape Detection and Behaviour Recognition

International Journal of Computer Vision, Journal Year: 2024, Volume and Issue: 132(8), P. 3086 - 3102

Published: March 4, 2024

Abstract We present the PanAf20K dataset, largest and most diverse open-access annotated video dataset of great apes in their natural environment. It comprises more than 7 million frames across $$\sim $$ ∼ 20,000 camera trap videos chimpanzees gorillas collected at 18 field sites tropical Africa as part Pan African Programme: The Cultured Chimpanzee. footage is accompanied by a rich set annotations benchmarks making it suitable for training testing variety challenging ecologically important computer vision tasks including ape detection behaviour recognition. Furthering AI analysis information critical given International Union Conservation Nature now lists all species family either Endangered or Critically Endangered. hope can form solid basis engagement community to improve performance, efficiency, result interpretation order support assessments presence, abundance, distribution, thereby aid conservation efforts. code are available from project website:

Language: Английский

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How abundant is a species at the limit of its distribution range? Crested porcupine Hystrix cristata and its northern population

Ecology and Evolution, Journal Year: 2024, Volume and Issue: 14(1)

Published: Jan. 1, 2024

Abstract The crested porcupine ( Hystrix cristata ) is a rodent present in Africa and southern Europe (Italy exclusively). Italian population expanding from the centre to north south, but little known about species' abundance. Reliable density estimates are important for monitoring trends wildlife populations developing effective conservation management strategies. In this context, we aimed first report on northern limit of its current distribution range using non‐invasive approach. Specifically, randomly placed 38 camera traps an area 242 km 2 Italy (Lombardy region), applied trap distance sampling. We estimated 0.49 ind·km −2 (±0.33, standard error). results presented here estimate accounting imperfect detection (i.e. species not detected). abundance reported fundamental better understanding status implementing plans.

Language: Английский

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Reducing bias in density estimates for unmarked populations that exhibit reactive behaviour towards camera traps

Methods in Ecology and Evolution, Journal Year: 2023, Volume and Issue: 14(12), P. 3100 - 3111

Published: Nov. 14, 2023

Abstract Density estimates guide wildlife management, and camera traps are commonly used to estimate sizes of unmarked populations. Unfortunately, animals often alter their natural behaviour in the presence traps, which may bias subsequent density estimates. We simulated 100 populations known test several new existing methods that aimed reduce from trap distance sampling (CTDS) random encounter model (REM). Within our populations, we introduced different behavioural reactions including attraction towards cameras, freezing when near cameras fleeing cameras. CTDS REM provided with decent coverage confidence intervals (CTDS = 94%, 87%), mean coefficient variation 0.121, 0.071) minimal (root‐mean squared error: 1.336, 0.913) for no reactive behaviour. However, failure implement a method account resulted low coverage, large potentially imprecise 30% population reacted by or traps. identified corrective strategy enhanced interval increased precision reduced every reaction except individuals fled Synthesis applications . provide empirically tested reducing Wildlife managers requiring exhibit can use inaccuracy. encourage future studies quantify responses implement, possibly extend through simulation.

Language: Английский

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Estimating effective survey duration in camera trap distance sampling surveys

Ecology and Evolution, Journal Year: 2023, Volume and Issue: 13(10)

Published: Oct. 1, 2023

Among other approaches, camera trap distance sampling (CTDS) is used to estimate animal abundance from unmarked populations. It was formulated for videos and observation distances are measured at predetermined 'snapshot moments'. Surveys recording still images with passive infrared motion sensors suffer frequent periods where animals not photographed, either because of technical delays before the can be triggered again (i.e. 'camera recovery time') or they remain stationary do immediately retrigger following time 'retrigger delays'). These effects need considered when calculating temporal survey effort avoid downwardly biased estimates. Here, we extend CTDS model sensor single short photo series. We propose estimating 'mean intervals between triggers' as combined mean interval distribution pairs consecutive pictures, using a Gamma Exponential function, respectively. apply approach data on red deer, roe deer wild boar. Mean triggers were very similar estimated empirically derived model-based approach. Depending truncation times pictures beyond which discarded) species, retriggers 8.28 15.05 s. Using predefined snapshot interval, accounting these intervals, would lead underestimated density by up 96% due overestimated effort. The proposed applicable any taxa surveyed traps. As programming cameras record often preferred over video reduced consumption energy memory, expect this find broad application, also methods than CTDS.

Language: Английский

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Camera traps unveil demography, social structure, and home range of six unhabituated Western chimpanzee groups in the Moyen Bafing National Park, Guinea

American Journal of Primatology, Journal Year: 2023, Volume and Issue: 86(2)

Published: Nov. 20, 2023

Precise estimates of population dynamics and social grouping patterns are required for effective conservation wild animal populations. It is difficult to obtain such information on non-human great apes as they have slow reproductive rates. To gain a better understanding demography in these populations, previous research has typically involved habituation\, process that requires years. Here, we collected data continuously over year-long periods monitor an unhabituated critically endangered Western chimpanzees (Pan troglodytes verus) the Moyen Bafing National Park, Guinea. We used two arrays 100 camera traps were placed opportunistically distinct km

Language: Английский

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Assessing mammal population densities in response to urbanization using camera trap distance sampling

Ecology and Evolution, Journal Year: 2023, Volume and Issue: 13(10)

Published: Oct. 1, 2023

Abstract Environmental filtering is deemed to play a predominant role in regulating the abundance and distribution of animals during urbanization process. However, current knowledge about effects on population densities terrestrial mammals limited. In this study, we compared two invasive (dogs Canis lupus familiaris cats Felis silvestris ) three indigenous (Siberian weasels Mustela sibirica , Amur hedgehogs Erinaceus amurensis Tolai hares Lepus tolai response using camera trap distance sampling (CTDS) rural–urban landscape Tianjin, China. We used generalized additive mixed models (GAMMs) test specific responses their levels urbanization. Invasive dogs (2.63 individuals/km 2 95% CI: 0.91–7.62) exhibited similar density estimations (2.15 1.31–3.50). were most abundant species (6.73 3.15–14.38), followed by (2.22 0.87–5.68) Siberian 1.06–4.36). The cats, weasels, increased with level only influenced urban‐related variables, while both variables nature‐related variables. Our findings highlight that CTDS suitable promising method for wildlife surveys landscapes, urban management needs consider integrated repercussions urban‐ factors, especially critical impacts green space habitats at finer scales.

Language: Английский

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Bonobo (Pan paniscus) Density and Distribution in Central Africa's Largest Rainforest Reserve: Long-term Survey Data Show Pitfalls in Methodological Approaches and Call for Vigilance

International Journal of Primatology, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 2, 2024

Language: Английский

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