Between the Lines
Chimpanzee insectivory is seasonally variable, with pronounced peaks or set seasonal periods of consumption observed in most chimpanzee communities. This variation is interesting given that chimpanzees invest considerable effort into complex tool‐using behaviors to acquire insect prey. Evidence suggests this seasonal variation is related to insect behavior, but few studies have been done to empirically examine this relationship. In this study, we assessed whether a seasonal pattern of termite fishing by Nigeria‐Cameroon chimpanzees (Pan troglodytes ellioti) in Mbam & Djerem National Park, Cameroon was driven by termite behavior. We measured termite presence and termite foraging activity monthly at seven termite mounds near Ganga Research Station from April 2022 to April 2023. Macroscopic fecal analysis and camera traps placed at each mound demonstrated termite fishing in this community occurred from March to June, with a rare smaller period of termite fishing in October 2021. Average monthly rainfall, average monthly temperature, and average monthly fruit availability were used to examine potential environmental factors that could impact termite fishing seasonality. Termite presence was significantly different between months with and without chimpanzee termite fishing (t‐test, −6.569, p < .001). Termite presence was also significantly associated with average monthly rainfall (ANOVA, F = 13.9, p = .002, R² = .775). Termites in this region appear to respond to the transition from dry to wet seasons by moving closer to the soil surface. This corresponds with greater chimpanzee termite fishing, suggesting that termite accessibility may be driving seasonal variation in this behavior.
(PDF) Freshwater Snail Inventory at Upper Delaware Scenic and Recreational River
The Upper Delaware Scenic and Recreational River (UPDE) unit of the National Park Service partnered with the Academy of Natural Sciences of Drexel University (ANS) to perform a freshwater snail inventory within the park. ANS and UPDE teams conducted field research in July and August of 2022 and 2023 using a combination of kick-net sampling and hand-picking methods to determine the abundance and diversity of freshwater snail populations. Fifty-four sites were surveyed along the 73 miles of the Delaware River within UPDE and included cold-water and warmwater fisheries zones. Snails were identified using traditional morphological taxonomy and DNA barcoding of the CO1 (Cytochrome c oxidase I) gene. Additional environmental DNA (eDNA) was analyzed from water collected at ten eDNA Atlas Sites. Based on genetic analysis, 27 species of gastropods were identified, one of which is a non-native species, the Japanese Mystery Snail (Cipangopaludina japonica). There were more snails below the Cannonsville Reservoir influence in the warmwater zone. A better understanding of the snail community and the ecosystem has been gained with the results of this inventory, which will inform effective and responsible river management plans.