Coupling of coastal activity with tidal cycles is stronger in tool-using capuchins ( Cebus capucinus imitator )

Abstract

Terrestrial mammals exploiting coastal resources must cope with the challenge that resource availability and accessibility fluctuate with tidal cycles. Tool use can improve foraging efficiency and provide access to structurally protected resources that are otherwise unavailable (e.g. molluscs and fruits). To understand how variable accessibility of valuable resources shapes behavioural patterns, and whether tool use aids in the efficient exploitation of intertidal resources, we compared the relationship between tidal cycles and activity patterns of tool-using versus non-tool-using groups of white-faced capuchin monkeys on Jicarón Island in Coiba National Park, Panama. Although tool use on Jicarón is localized to a small stretch of coast (approx. 1 km), all coastal groups forage on intertidal resources. Using more than 5 years of camera trap data at varying distances from the coast, we found that capuchins on Jicarón showed increased coastal activity during specific parts of the tidal cycle, and that this relationship differed between tool-using and non-tool-using groups, as well as between seasons. Activity patterns of tool-using capuchins were more strongly and consistently tied to tidal cycles compared with non-tool-users, indicating that tool use might allow for more efficient exploitation of tidal resources. Our findings highlight the potential of tool use to aid niche expansion.

Male‐biased stone tool use by wild white‐faced capuchins (Cebus capucinus imitator)

“…White‐faced capuchins living on Jicarón and Coiba island are unhabituated, and thus all data presented here originates from indirect means of data collection, primarily via the deployment of camera traps. The group size of the Jicarón tool‐using group appears to be between 20 and 25 individuals, with at least 5 adult males and 5 or 6 adult females (fluctuating throughout the data collection) (for details on group identification, see Goldsborough et al, 2023). Less is known about the tool‐using group on Coiba island, so we cannot make estimates of group size or composition.…”

“…If they foraged, even briefly, this was coded instead. We calculated the distance of each camera site on Jicarón to the coast by taking the distance from a camera's GPS point to the nearest coastal vegetation boundary (for more details see Goldsborough et al, 2023).…”

Male-biased stone tool use by wild white-faced capuchins (Cebus capucinus imitator)

“…White-faced capuchins living on Jicarón and Coiba island are unhabituated, and thus all data presented here originates from indirect means of data collection, primarily via the deployment of camera traps. The group size of the Jicarón tool-using group appears to be between 20-25 individuals, with at least 5 adult males and 5 or 6 adult females (fluctuating throughout the data collection) (Goldsborough et al, in press). Less is known about the tool-using group on Coiba island, so we cannot make estimates of group size or composition.…”

“…If they foraged, even briefly, this was coded instead. We calculated the distance of each camera site on Jicarón to the coast by taking the distance from a camera’s GPS point to the nearest coastal vegetation boundary (for more details see Goldsborough et al, in press).…”

Primate archaeology 3.1

“…There are also sex biases in some of the Panamanian Cebus groups, with males using tools more than females (Barrett et al, 2018), which joins examples such as male bias in probing tools among some Sapajus groups (Fal otico et al, 2021) to aid discussions going beyond technology into the social and developmental realms of past primates. While the most recent reports of Cebus tool use appeared too late for inclusion in the review (e.g., Goldsborough, Crofoot, Alavi, et al, 2023;Goldsborough, Crofoot, & Barrett, 2024)…”