Seasonal nutritional ecology of the black and gold howler monkey (Alouatta caraya) in Argentina

JESSICA ROTHMAN; FERNANDEZ VANINA

New York City

Conferencia; 2nd Northeastern Evolutionary Primatology; 2016

The Northeastern Evolutionary Primatology Group

There are different feeding patterns in primates that reflect the wide variation in the macronutrient composition of their foods. We applied the Geometric Framework to explore seasonal strategies used in the food selection of howler monkeys (Alouatta caraya) inhabiting the southern limit of its distribution in Argentina. We collected 482 observational hours (June-December 2010, two groups) including 48 full day focal follows (2 males and 5 females). We analyzed the nutritional composition of 146 samples of food eaten from 27 species and 7 food parts, and estimated daily nutrient intake. Average monthly energy intake was 1011.22 ± 149.26 KJg-1mbm-1 (CV = 14.76%) of which 842.57 ± 117.66 KJg-1mbm-1 corresponded to non-protein energy (NPE) (CV = 13.96%) and 168.66 ± 35.13 KJg-1mbm-1 available protein (CV = 20.83%) an intake equivalent to 9.92 ± 2.1 gmbm-1 of daily protein. However, these values were highly variable among months (CVEnergy = 50.32%, CVNPE= 53.24 %, CVP = 62.99%), individuals, and groups, and there were two nutritional rails of NPE:P intake. In October and November, months of high-fruit intake (>80%, dry matter basis), NPE:P was 11.44 ± 0.71 and protein represents 21.34 ± 2.11% of total energy consumed. By contrast, in periods of less fruit intake (< 62%, dry matter basis) the NPE balance was 4.0 ± 0.81 and protein represents 8.26 ± 0.43% of total energy consumed. Understanding nutritional strategies of howlers could help us to understand how howlers are capable of coping with marginal environments across their distribution.