Primate population surveys



Population surveys of Alouatta palliata, A. pigra and Ateles geoffroyi:

This line of research is aimed at gathering information about where populations are located and about the size and demographic structure of such populations. Explorations of remote areas harboring extensive forest tracts is a priority, but adjacent fragmented landscapes are also surveyed. Once populations are found, we proceed to obtain data on their size and demographic structure, as well as on their state of conservation and that of their habitats. Some sites in southern Mexico are the focus of medium and long-term monitoring of populations of the three species.

Sites of concentration of medium and long-term primate surveys are shown with the yellow dots. From left to right: Los Tuxtlas; Comalcalco, Yumká and La Venta in Tabasco; Palenque, Bonampák, Lacanjá and Yaxchilán in Chiapas; Calakmul and El Tormento in Campeche; and the biosphere reserve of Celestúm in the northwest corner of the Yucatan peninsula. The red broken line shows the general geographic area ecompassed by our surveys. Sites are also being surveyed in Guatemala (e.g. Tikal to the north and the Lachua Reserve to the south, both within the Guatemalan Peten.

Some of the sites surveyed are the protected forests surrounding many Mayan archeological sites



In 2002 these surveys have been extended to Bermiuda Landing in Belize and Tikal in Guatemala, with the aim of having comparative data for Alouatta pigra and Ateles geoffroyi from these localities.


Population surveys of wild primates in southern Mexico are conducted on foot, horseback, boat and even with the use of ultralight aircratfts.


Sarie Van Belle (Univ. de Ghent, Bélgium) and LeAndra Lluecke (Univ. of Texas-Austin), members of our primate research team, reading a GPS used to track movement of troops and map detections of primates in Calakmul, Campeche.




Searching for primates in the rain forests of southern Mexico involves exploring remote areas where we do much walking and in many different kinds of forests and terrains. We navigate rivers, some of them very popular with crocodiles, climbw to the top of many Mayan pyramids to track the monkeys sounds or movements in the canopy below or to observe their behavior. As explorations are conducted we also encounter other forest fauna, such as white-lipped peccaries, coatis, felines, toucans, crested eagles, etc.

Demographic parameters of primate populations under consideration in these studies are the size of the population, number of troops or subgroups, distribution of age and sex classes, sex ratios among adults and non adults, adult female to immature ratios, etc. Population density with respect to the area sampled as well as the state of conservation of the primate habitat is also important measures. General conservation pressures such as habitat destruction and degradation, degree of habitat fragmentation, extraction of hardwoods, hunting and traffic of infants as pets are variables investigated in our studies.


Housing conditions of field work for our team range from the magnificent infrastructure of the field station Los Tuxtlas to more rustic facilities, where most of the time we camp by the edge of or inside the forest, and take turns cooking our meals.




Results of these surveys can be found in the publications listed under "publications of the primate lab" in the main page.

Support the conservation of tropical rain forests and their primates in southern Mexico

Copyright @ 2006 Alejandro Estrada

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