TY - JOUR AU - André L. Koch Liston AU - Xueying Zhu AU - Tran V. Bang AU - Phaivanh Phiapalath AU - Tanvir Ahmed AU - Sabit Hasan AU - Sajib Biswas AU - Shimul Nath AU - Toufique Ahmed AU - Kurnia Ilham AU - Ngwe Lwin AU - Cain Agger AU - Suzuki Ai AU - Emeline Auda AU - Eva Gazagne AU - Jan F. Kamler AU - Milou Groenenberg AU - Sarah Banet-Eugene AU - Neil Challis AU - Nicole Leroux AU - Pablo Sinovas AU - Vanessa H. Muñoz AU - Susan Lappan AU - Zaki Zainol AU - Valeria Albanese AU - Athanasia Alexiadou AU - Daniel R. K. Nielsen AU - Anna Holzner AU - Nadine Ruppert AU - Elodie F. Briefer AU - Agustin Fuentes AU - Malene F. Hansen AB - Accurately estimating population sizes for free-ranging animals through noninvasive methods, such as camera trap images, remains particularly limited by small datasets. To overcome this, we developed a flexible model for estimating upper limit populations and exemplified it by studying a group-living synanthrope, the long-tailed macaque (Macaca fascicularis). Habitat preference maps, based on environmental and GPS data, were generated with a maximum entropy model and combined with data obtained from camera traps, line transect distance sampling, and direct sightings to produce an expected number of individuals. The mapping between habitat preference and number of individuals was optimized through a tunable parameter ρ (inquisitiveness) that accounts for repeated observations of individuals. Benchmarking against published data highlights the high accuracy of the model. Overall, this approach combines citizen science with scientific observations and reveals the long-tailed macaque populations to be (up to 80%) smaller than expected. The model’s flexibility makes it suitable for many species, providing a scalable, noninvasive tool for wildlife conservation. BT - Science Advances DA - 2024-05-24 DO - 10.1126/sciadv.adn5390 IS - 21 N2 - Accurately estimating population sizes for free-ranging animals through noninvasive methods, such as camera trap images, remains particularly limited by small datasets. To overcome this, we developed a flexible model for estimating upper limit populations and exemplified it by studying a group-living synanthrope, the long-tailed macaque (Macaca fascicularis). Habitat preference maps, based on environmental and GPS data, were generated with a maximum entropy model and combined with data obtained from camera traps, line transect distance sampling, and direct sightings to produce an expected number of individuals. The mapping between habitat preference and number of individuals was optimized through a tunable parameter ρ (inquisitiveness) that accounts for repeated observations of individuals. Benchmarking against published data highlights the high accuracy of the model. Overall, this approach combines citizen science with scientific observations and reveals the long-tailed macaque populations to be (up to 80%) smaller than expected. The model’s flexibility makes it suitable for many species, providing a scalable, noninvasive tool for wildlife conservation. PY - 2024 EP - eadn5390 T2 - Science Advances TI - A model for the noninvasive, habitat-inclusive estimation of upper limit abundance for synanthropes, exemplified by M. fascicularis UR - https://www.science.org/doi/10.1126/sciadv.adn5390 VL - 10 Y2 - 2025-10-10 ER -