Ranging behavior of translocated and established groups of black howler monkeys Alouatta pigra in Belize, Central America

An experimental census method and estimates of population density of a black howler monkey (<i>Alouatta pigra</i>) highland population in the Sierra Yalijux, Guatemala

“…However it remains open whether or not A. pigra crowds in response to the decreased habitat (Markussen and Renner, 2005). Other research teams report crowded populations from fragmented forest patches in Belize (Silver et al, 1998;Chapman and Balcom, 1998;Ostro et al 1999Ostro et al , 2000Horwich et al, 2001) with approximately twice as high population densities than we found in the Sierra Yalijux (compare above).…”

“…For example, lower densities are reported for A. pigra in various sites in Mexico (Gonzales-Kirchner, 1998;Estrada et al, 2002a;Estrada et al, 2004) (Horwich et al 2001). The population was considered to be crowded due to fragmentation (Silver et al, 1998;Ostro et al 1999Ostro et al , 2000Horwich et al, 2001). The Sierra Yalijux has a clearly higher population density than the Mexican and northern Guatemalan sides but is still below numbers from more fragmented landscapes of Belize.…”

Hábitat y población de mono tití (Cebidae: Saimirioerstediioerstedii) en la península de Osa, Costa Rica

“…El bosque primario es utilizado por los monos tití como conexión entre parches de bosques en regeneración, o estacionalmente, cuando la disponibilidad de alimento como artrópodos, frutos y flores es muy baja en los bosques secundarios (Boinski 1986) y los monos aprovechan frutos de especies que se desarrollan en el bosque primario (Wong 1990a). Diferencias en el uso de un hábitat, dependiendo de la estacionalidad de la disponibilidad de alimento, se han encontrado en estudios anteriores con otros primates neotropicales también (Ostro et al 1999). Esto podría explicar la baja probabilidad de hallar a los monos tití cuando se realizó el tercer conteo en la mayoría de los sitios de bosque, probablemente por su desplazamiento en busca de especies fructificando en el bosque primario (Wong 1990b).…”

Hurricanes and coastlines: The role of natural disasters in the speciation of howler monkeys

“…Each of these severe weather events caused a drastic decline in population numbers, and although they have recovered, the average group size in this region is only 4.6 individuals, lower than most other species of howlers. In 1999 this number increased to between four to 10 individuals, which although larger, is still smaller than other howler species (Ostro et al, 1999). A similar decline in group size was recorded in Monkey River following Hurricane Iris where group size remains smaller than before the storm even after more than a decade has passed.…”

“…The highest published densities reported for A. pigra have been at the Community Baboon Sanctuary (CBS) near the Belize River (257 ind/km 2 , Ostro et al, 1999) and at Monkey River (102 ind/ km 2 , Pavelka, 2003). Seasonally flooded forests create localised disturbance which may improve soil quality and thus the quality of the howler food supply (Peres, 1997).…”