Importance of subterranean fungi in the diet of bonobos in Kokolopori

• Published in: American journal of primatology Vol. 83; no. 9; pp. e23308 - n/a
• Main Authors: Lucchesi, Stefano, Cheng, Leveda, Wessling, Erin G., Kambale, Bienfait, Lokasola, Albert L., Ortmann, Sylvia, Surbeck, Martin
• Format: Journal Article
• Language: English
• Published: New York Wiley Subscription Services, Inc 01-09-2021
• Subjects: Abundance; apes; Diet; Ecology; fallback food; Food; Food consumption; Food sources; Fruit; Fruits; Fungi; Hypotheses; Insects; Meat; Mycophagy; Nutrients; nutritional content; Pan paniscus; Patches (structures); Primates; Sodium; staple food; Travel
• ISSN: 0275-2565; 1098-2345
• DOI: 10.1002/ajp.23308

Nonstaple food is a food resource which sole consumption does not allow the maintenance of regular physiological functions, thus constituting a minor portion of an individual's diet. Many primates consume nonstaple food such as meat, insects, and fungi. Hypotheses on the dietary importance of nonstaple food include its role as fallback food and as source of specific nutrients. We tested these two hypotheses by investigating mycophagy (i.e., the consumption of fungi) in a population of wild bonobos in the Kokolopori Bonobo Reserve, DRC. Specifically, we examined the relationship between fungus consumption and various factors relevant to bonobo feeding ecology (i.e., fruit abundance and the consumption of other food types). Additionally, we measured the deviation from linear travel when bonobos searched for fungi to evaluate the nature of fungus consumption (e.g., opportunistic or targeted). Lastly, we examined the nutritional content of the major fungus species consumed (Hysterangium bonobo) to test whether this food item was potentially consumed as source of specific nutrients. We found that bonobos spent a higher proportion of their time feeding on fungi when fruit abundance was higher, indicating that fungi were not consumed as a fallback food. Moreover, bonobos deviated from linear travel when visiting fungus patches more than observed when visiting fruit patches, suggesting that they actively sought out fungi. Lastly, initial analyses suggest that H. bonobo samples contained high concentration of sodium. Collectively, these results suggest that subterranean fungi appear to be attractive food source to Kokolopori bonobos, and that mycophagy may serve to supplement nutrients, like sodium, in bonobo diet.
Research Highlights
Bonobos spent proportionately more time consuming fungi when fruit abundance was higher, suggesting mycophagy is not a fallback food strategy in Kokolopori.
Bonobos actively sought out fungi and did not consume them opportunistically on their shortest route between fruit patches.
Mycophagy likely serves to supplement sodium in the diet of Kokolopori bonobos.