Details

Autor(en) / Beteiligte

• Blumenthal, Scott A.
• Chritz, Kendra L.
• Rothman, Jessica M.
• Cerling, Thure E.

Titel

Detecting intraannual dietary variability in wild mountain gorillas by stable isotope analysis of feces

Ist Teil von

• Proceedings of the National Academy of Sciences - PNAS, 2012-12, Vol.109 (52), p.21277-21282

Ort / Verlag

United States: National Academy of Sciences

Erscheinungsjahr

2012

Link zum Volltext

Quelle

EZB Free E-Journals

Beschreibungen/Notizen

• We use stable isotope ratios in feces of wild mountain gorillas (Gorilla beringei) to test the hypothesis that diet shifts within a single year, as measured by dry mass intake, can be recovered. Isotopic separation of staple foods indicates that intraannual changes in the isotopic composition of feces reflect shifts in diet. Fruits are isotopically distinct compared with other staple foods, and peaks in fecal δ ¹³C values are interpreted as periods of increased fruit feeding. Bayesian mixing model results demonstrate that, although the timing of these diet shifts match observational data, the modeled increase in proportional fruit feeding does not capture the full shift. Variation in the isotopic and nutritional composition of gorilla foods is largely independent, highlighting the difficulty for estimating nutritional intake with stable isotopes. Our results demonstrate the potential value of fecal sampling for quantifying short-term, intraindividual dietary variability in primates and other animals with high temporal resolution even when the diet is composed of C ₃ plants.