Growth of Mantled Howler Groups in a Regenerating Costa Rican Dry Forest

摘要: We examined population dynamics in mantled howlers (Alouatta palliata palliata) a regenerating tropical dry forest Santa Rosa National Park (SRNP), Costa Rica. The has grown at rate of about 7% per annum during the past decade. growth numbers from 342 1984 to 554 1992 reflects an increase number groups (from 25 34) and slight their average size 13.6 16.3). Population density increased 4.9 7.9 individuals km2. Rosa's group compositions are similar those several other howler sites, but densities much higher two well-studied sites: La Pacifica Barro Colorado Island (BCI). relate low local historical ecological factors. Howler populations high differ sex ratio. At densities, larger include more adult females. male appears be strictly limited less variable than females is. However, there is greater variation membership or BCI, generating forests available into which males can disperse form new groups. present case studies describing ways formed, we suggest that, compared relatively advantaged uncrowded habitats sites.