Use of mineral licks by mammals in areas of the Amazonia with no hunting pressure

Mineral licks are areas where several species of animals, including mammals, converge to consume water and soil as a mineral supplement. Certain mammal species are an important source of protein in the diet of indigenous communities. Many of these species are under hunting pressure and their populations have been seriously affected. The purpose of this study was to determine the species of large and medium-sized mammals that use three open mineral licks in the area of the Kichwa Añangu community, within the Yasuní National Park, where hunting used to take place. We calculate the capture frequency for the visiting species and the richness, composition, and similarity of the assemblages recorded in the mineral licks during two climatic seasons of the year (higher rainfall vs. lower rainfall). We installed a single camera trap station (CTS) at each mineral lick during three sampling periods in 2018. In each period, all cameras operated 24 hours a day for 30 to 40 days and were set to capture three photographs upon sensor activation, with 60-second intervals between consecutive activations. With a total sampling effort of 249 days/trap, we obtained 645 photographs and 398 grouped records of 16 species. We recorded 95.2 % of the expected richness according to the Chao1 estimator (S = 16.8). The species with the highest capture frequency were: Mazama zamora (FC = 62.2), Tayassu pecari (FC = 35.7), Tapirus terrestris (FC = 28.9), and Pecari tajacu (FC = 8.0). ECT-1 and ECT-2 captured 11 species each, and ECT-3 captured nine species. There were no significant differences in the species composition between the three mineral licks or between climatic seasons. Our results show that the focal mineral licks studied attract a rich mammalian fauna, which likely points to the success of the government regulation of wildlife trafficking and the application of sustainable tourism practices in the Añangu community.

Hunting pressure modulates the composition and size structure of terrestrial and arboreal vertebrates in Amazonian forests

Overhunting is a leading contemporary driver of tropical forest wildlife loss. The absence or extremely low densities of large-bodied vertebrates disrupts plant-animal mutualisms and consequently degrades key ecosystem services. Understanding patterns of defaunation is therefore crucial given that most tropical forests worldwide are now “half-empty”. Here we investigate changes in vertebrate community composition and size structure along a gradient of marked anthropogenic hunting pressure in the Médio Juruá region of western Brazilian Amazonia. Using a novel camera trapping grid design deployed both in the understorey and the forest canopy, we estimated the aggregate biomass of several functional groups of terrestrial and arboreal species at 28 sites along the hunting gradient. Generalized linear models (GLMs) identified hunting pressure as the most important driver of aggregate biomass for game, terrestrial, and arboreal species, as well as nocturnal rodents, frugivores, and granivores. Local hunting pressure affected vertebrate community structure as shown by both GLM and ordination analyses. The size structure of vertebrate fauna changed in heavily hunted areas due to population declines in large-bodied species and apparent compensatory increases in nocturnal rodents. Our study shows markedly altered vertebrate community structure even in remote but heavily settled areas of continuous primary forest. Depletion of frugivore and granivore populations, and concomitant density-compensation by seed predators, likely affect forest regeneration in persistently overhunted tropical forests. These findings contribute to a better understanding of how cascading effects induced by historical defaunation operate, informing wildlife management policy in tropical peri-urban, rural and wilderness areas.

Wildlife Hunting and Utilization in Ulu Baleh, Sarawak, Malaysian Borneo

Poaching is one of the greatest immediate threats and a serious conservation challenge facing wildlife in Borneo. Medium- to large-sized mammals, while charismatic, are hunted for consumption and sale. This study focuses on wildlife hunting and utilization of selected communities in a remote area in Sarawak, conducted using interview surveys within communities who hunt wildlife in Ulu Baleh. The calculated hunting pressure index in Ulu Baleh (2.24) is considered low compared to other parts of Sarawak. Local communities are dependent on wildlife protein and medicine. Even though the common hunting offtake included the bearded pig and deer species, for the hunter’s own consumption, hunters were opportunistic in taking non-target species and selling surplus meat. Lack of awareness of the implications of unsustainable hunting and difficulty in monitoring by the relevant authorities appear to be the main challenges to wildlife conservation in the area. This paper highlights the lack of research documenting wildlife utilization in the Ulu Baleh region and the implication of these results are particularly important for future adaptive wildlife management, especially for species of conservation importance in Sarawak.