While using the word fishing is perhaps a bit misleading (though some chimpanzees and orangutans do apparently go fishing with their hands sometimes), new research has found that a population of wild chimpanzees in Bakoun, Guinea regularly go fishing for algae during the dry season using sticks. Sometimes these sticks used are very long, up to 4 meters, and require a great deal of skill to use properly.
Chimpanzees are of course now known to make use of very wide variety of tools depending on the goal in question, and for that matter to exhibit a lot of comprehension of the tools used by humans — with some populations even being found to intentionally disable dangerous snare traps in their territories, and to teach their offspring to do so as well.
The new findings are part of the Department of Primatology at the Max Planck Institute for Evolutionary Anthropology’s ‘Pan African Programme: The Cultured Chimpanzee’ — which is intended to explore the behavior of poorly studied chimpanzees populations.
The press release provides more: “Since chimpanzees are not habituated to human presence at the PanAf sites, the researchers rely on a wide spectrum of non-invasive sampling methods, including remote camera traps. After discovering conspicuous sticks along some of the rivers and ponds in Bakoun, PanAf site manager Anthony Agbor placed camera traps along these bodies of water.”
“The tool-use appears quite different from what is known from a nearby long-term chimpanzee site at Bossou, Guinea and also differed from previous reports of rare algae scooping in Congo,” commented Ammie Kalan of the Max Planck Institute for Evolutionary Anthropology. “All age and sex classes of Bakoun chimpanzees were seen in the camera trap videos to successfully fish for algae in a river, stream or pond using woody branches or twigs as fishing rods. The tools were on average longer and sturdier than the algae fishing tools that are known from Bossou. Some Bakoun tools were more than 4 meters long!”
Notably, the freshwater green algae being targeted is within the same genus as that at Bossou (Spirogyra), at the Bakoun site though the algae grows on the bottom of the stream beds and doesn’t seem accumulate at the surface as at Bossou. Presumably this algae is either particularly tasty to the local chimpanzees, or it serves some important nutritional need during the dry season.
“The ecology of the particular algae growing at each site may drive the types of tools necessary to harvest the algae,” stated Christophe Boesch, Director of the Primatology Department at the Max Planck Institute for Evolutionary Anthropology, “We suggest that the algae probably provide an important nutritional benefit to the chimpanzees at Bakoun, especially during the dry season when chimpanzees were observed to fish algae for up to an hour at the same spot.”
Those interested are able to watch the videos in question, and a great many others at the PanAf ChimpAndSee site, where viewers can leave annotations to the videos in question as well. (For more generalized information on chimpanzees and other endangered primates, see: Endangered Primates Species List — Bili Chimpanzees, Apes, Mountain Gorillas, Howler Monkeys, Blue Eyed Black Lemur, Tarsiers, Tamarins, Gibbons, etc.)