title: Fluid dipping technology of chimpanzees in Comoé National Park, Ivory Coast.
abstract: Over a 6 month period during the dry season, from the end of October 2014 to the beginning of May 2015, we studied tool use behavior of previously unstudied and non-habituated savanna chimpanzees (Pan troglodytes verus) living in the Comoé National Park, Ivory Coast (CI). We analyzed all the stick tools and leaf-sponges found that the chimpanzees used to forage for ants, termites, honey, and water. We found a particular behavior to be widespread across different chimpanzee communities in the park, namely, dipping for water from tree holes using sticks with especially long brush-tip modifications, using camera traps, we recorded adults, juveniles, and infants of three communities displaying this behavior. We compared water dipping and honey dipping tools used by Comoé chimpanzees and found significant differences in the total length, diameter, and brush length of the different types of fluid-dipping tools used. We found that water dipping tools had consistently longer and thicker brush-tips than honey dipping tools. Although this behavior was observed only during the late dry season, the chimpanzees always had alternative water sources available, like pools and rivers, in which they drank without the use of a tool. It remains unclear whether the use of a tool increases efficient access to water. This is the first time that water dipping behavior with sticks has been found as a widespread and well-established behavior across different age and sex classes and communities, suggesting the possibility of cultural transmission. It is crucial that we conserve this population of chimpanzees, not only because they may represent the second largest population in the country, but also because of their unique behavioral repertoire.
authors.affiliation: Animal Ecology and Tropical Biology, Biozentrum, Universität Würzburg Tierökologie und Tropenbiologie (Zoologie III), Würzburg, Germany.
authors.forename: Juan
authors.initials: J
authors.lastname: Lapuente
authors.affiliation: The Faculty of Artes Liberales, University of Warsaw, Warsaw, Poland.|Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
authors.forename: Thurston C
authors.initials: TC
authors.lastname: Hicks
authors.affiliation: Animal Ecology and Tropical Biology, Biozentrum, Universität Würzburg Tierökologie und Tropenbiologie (Zoologie III), Würzburg, Germany.
authors.forename: K Eduard
authors.initials: KE
authors.lastname: Linsenmair
mesh_terms: D000818:Animals; D007560:Cote d'Ivoire; D005247:Feeding Behavior; D005260:Female; D008297:Male; D002679:Pan troglodytes / Q000502:physiology*; D000068316:Parks, Recreational; D053001:Tool Use Behavior
keywords: Western chimpanzee (Pan troglodytes verus); brush tipped tool; fluid dipping; tool use; water-acquisition