Infant mortality in Alouatta caraya living in a flooded forest in Northeastern Argentina

PAVÉ, ROMINA; MARTIN KOWALEWSKI; PAUL GARBER; GABRIEL ZUNINO; VANINA FERNANDEZ; SILVANA PEKER

INTERNATIONAL JOURNAL OF PRIMATOLOGY

SPRINGER/PLENUM PUBLISHERS

Lugar: New York; Año: 2012 vol. 33 p. 937 - 957

0164-0291

Ecological and social factors have a significant effect on infant survivorship in non-human primates. We present 6,293 group months of infant birth and mortality data for 29 groups of Alouatta caraya inhabiting a flooded forest in Northeastern Argentina, collected over 1.5-8 years depending on the group. We tested whether infant mortality was a response to the effects of flooding on food availability and whether male takeovers resulted in greater opportunities for infanticide. During our study, 43 of 113 infants died at a mean age of 5 months. In 24 cases the cause of death was unknown. In the remaining 19 cases infant deaths were attributed to periods of intense flooding (N=8), replacement of the breeding male N=8), problems associated with birth (N=2), and injuries during an intergroup encounter (N=1). Flooding reduced the availability of mature leaves, which appeared to play an important role in the ability of mothers to nurse their offspring. Male replacements occurred in 4 social groups that contained only one fully adult male. Infant mortality was significantly higher in groups that experienced male replacement compared to groups without male replacement. These results indicate that infant mortality in A. caraya is affected by several factors (natural disasters, maternal condition and food availability, infanticide following male replacement, and possibly disease and predation), each of which needs to be evaluated in order to understand the history and demography of this primate population.