Getting through the winter: Dry season resources and their influence on owl monkeys (Aotus azarae) reproduction.

VAN DER HEIDE, GRIETJE; VICTOR DAVALOS; CECILIA PAOLA JUÁREZ; EDUARDO, FERNANDEZ-DUQUE

Alpine, Texas

Congreso; Texas Academy of Science Annual Meeting; 2012

Texas Academy of Sciences

Limiting food resource availability during yearly dry season has the potential to profoundly impact primate population dynamics and thereby direct effectively life history evolution. We examined the relation between dry season fruit availability, foraging ecology, and owl monkey (Aotus azarai) group demography. This monogamous primate species occupies small territories U3-6 ha). To evaluate resource availability in four territories during dry seasons (2008-2009), we collected, twice a month, data on tree fruiting phenology (5 spp.; n)894). We also collected ranging and foraging data during 2 full day (>10ha) follows per week for each group (n=4) and ad libitum half day (3-10 h) follows. We checked group demography at least monthly. Results indicate that while there were significant interannual (p<0.05; 2008-2009) differences in fruit availability territories did not differ in availability of most fruit species (p>0.05). Whereas in 2008 they foraged mainly for Chrysophyllum gonocarpum, Ficus spp., and epiphytes (63% fruits, 11% leaves), in 2009 they foraged for Ficus spp., Guazuma ulmifolia, and lianas (42%fuirts, 39% leaves). In 2008 one group and in 2009 three groups had an infant. Groups tended to be smaller in 2009. In spite of drastically lower fruit availability during dry season 2009, female were able to maintain pregnancy and give birth during spring. Their flexible foraging behaviour, natal dispersal during dry season 2008, and a general lack of births in 2008 may have facilitated this, suggesting that dry season food availability did not limit fecundity.