Malignant Snare Traps Threaten an Irreplaceable Megafauna Community

Abstract

Tropical forests are under severe threat from over-hunting. Subsistence harvests and poaching have decimated wildlife populations to the extent that nearly 50% of Earth’s tropical forests are partially or fully devoid of large mammals. Declines are particularly acute in Southeast Asia where ongoing defaunation, largely attributable to indiscriminate snare trapping, is widespread. Using the extensively forested Aceh province in northern Sumatra as a case study, we document rampant snaring, which threatens Earth’s last sympatric population of tigers, rhinoceros, elephants, and orangutans. To prevent catastrophic hunting-induced impacts already experienced in mainland Southeast Asia, we call for more comprehensive conservation planning assessments that strengthen wildlife law enforcement, promote collaborative anti-poaching, and research species-specific snaring impacts, particularly in the context of human-wildlife conflict. We conclude with a discussion of the important linkages between poaching, wildlife trade, and zoonotic disease risk.

Megafauna extinctions produce idiosyncratic Anthropocene assemblages

“…The peculiar distributions of Asian megafauna are an enduring puzzle for biogeographers, ecologists, and conservation biologists. While there is broad consensus that poaching and deforestation are the primary causes of dramatic declines across the region (26,36), we also noted high diversity in tropical forests surrounded by agriculture and settlements, such as Bukit Barisan Selatan, Pasoh, and Khao Yai. This suggests that some megafauna can persist in disturbed landscapes where there is effective management.…”

“…High mammal abundances of Khao Yai may also arise from being part of the Indo-Malayan biogeographic subregion, being more deciduous, and having managed grasslands, compared to all other study landscapes located in the Sundaic biogeographic subregion and which have evergreen rainforest and no grasslands ( 35 ). On the contrary, the lack of anti-poaching enforcement in some larger and more remote parks ( 36 ) may explain the recent extirpation of tigers from Ulu Muda, one of our largest and least disturbed landscapes. Overall, while there were some predictable outcomes, Southeast Asia’s remaining megafauna often showed divergent responses to the same threats, which has been partially noted by past work ( 37 ).…”

Effect of Anthropogenic Activities on the Population of Moor Macaques (Macaca maura) in South Sulawesi, Indonesia

“…We detected no stability, convergence, and dispersion problems with the GLMM, using the DHARMa package (Hartig, 2021). Variance Inflation Factors (VIFs) were minimal for all test predictors (maximum VIF = 1.95), indicating low collinearity (Field, 2005).…”

Review: The status of the endangered Eld’s deer (Rucervus eldii) and conservation actions in Thailand

“…In the past, poaching in protected areas in Thailand was severe (Jenks et al 2012). Enforcement of wildlife laws is one of the greatest determinants of megafauna persistence and recovery (Aryal et al 2017;Figel et al 2021). Ranger patrols, which generally rely on deterrence to motivate compliance, have been the major focus of anti-poaching strategies (Duangchantrasiri et al 2016;Risdianto et al 2016).…”

“…It is, therefore, unsurprising that large to medium-bodied mammals in Southeast Asia have extirpated from more than 80% of their geographic ranges (Duckworth et al 2012) and have undergone significant population losses (Dirzo et al 2014;Benítez-López et al 2017;Ceballos et al 2017;Gallego-Zamorano et al 2020). Poachers have also developed new hunting methods, including steel and wire traps, which are used effectively throughout the species range (Gray et al 2017(Gray et al , 2018Evans et al 2020;Belecky and Gray 2021;Figel et al 2021;Gray et al 2021). The ungulates are targeted for their meat, as well as for pest control, as they sometimes forage in agricultural crops (Ripple et al 2015), while large carnivores, porcupines and birds are targeted by poachers for sale (Heinrich et al 2020) which causes wildlife to be seriously threatened in Southeast Asia (Harrison et al 2016;Wolf and Ripple 2017;Benítez-López et al 2019).…”