Mammal Monitoring Program

Program Directors: Dr. Jacalyn Giacalone  Gregory E. Willis, and Ricardo Moreno

A. Continue BCI Mammal Census and Fruitfall Monitoring:  The goal of this census project is to provide long-term (30-year) data collection.  The data are to be used for analysis and comparison of census fluctuations with fruitfall and weather data, and to interpret these data in light of conclusions in the literature based on shorter-term data-sets from BCI, as well as from other tropical sites.   The data collected will include: -100+ km Strip Census on all BCI trails, for all diurnal mammal species, every January as done previously.  Data recording includes time, individuals, locations, distance from observer, distance from trail, and height above ground. -10 to 20 km of nocturnal census records every season. -Dipteryx  fruit crop monitoring by “removal plot” counts for the same13 trees included in the Glanz census work since 1980. The importance of this tree to the successful start of breeding for several key prey species makes it an essential species to monitor, particularly during the time of fruit shortage in January.  Late or small crops may have a widespread impact on some components of the mammal fauna. -Squirrel trapping-mark-resighting data in a 10-hectare intensive-study area.  For collecting comparative census data, and mortality, survivorship, and longevity estimates. Based on trapping every two years. -Squirrel mating chase numbers, locations, dates, marked individuals, as an indicator of the onset, vigor, and simultaneity of the breeding season. -Squirrel feeding records, gathered as defined by Heaney, to provide an index of availability of preferred foods. -Brocket deer feeding observations.  -Astrocaryum and Scheelea fruit crop census carried out annually for the last 7 seasons by estimating fruit cluster sizes for 60 trees. -Maintain at least 10 camera-traps on BCI to detect the more difficult to observe species.
B. Cat Study:  The development of fuller data on the larger predators on BCI is vital to interpreting the strip census data, which are biased toward the terrestrial prey species.  The use of several sources of data in combination are fundamental to our success in elucidating cat biology on BCI.  These sources of data include the collection of scats, tracks, and photographs, as well as a proposed radio-tracking project that will benefit from the wireless system under construction on BCI. Trip-camera data collected from cameras placed under fruiting trees and on game trails have provided data on the presence and numbers of elusive species such as puma, ocelot, and jaguarundi.  Our cameras are in continuous use since January ‘99, and seasonal data extend to ‘94.  Our photographs show that the first ocelot photographed by us in 1994 is still living after 7 years, that there are now at least 32 ocelots on the island, and that individuals other than the alpha males have tightly defined areas of activity.  We have also taken the first photograph of a jaguarundi on  BCI.  These data have been combined with an extensive collection of scats, tracks, and preliminary radio-tracking data from one male ocelot, enabling us to develop a more complete interpretation of the movements and population size of BCI ocelots.   Puma scats, tracks, and photos have made it clear that there is an on-going, but nearly invisible presence of two or more pumas on BCI.  The analysis of the ocelot and puma scat data in conjunction with the strip census data on prey species will contribute to the examination of predator-prey relations on BCI.
C.  Train a new, young cadre of Panamanian professionals to carry on the project.  The development of long-term census data is essential to understanding population fluctuations in tropical forests, as well as their implications for conservation decisions.   These data need to be collected consistently, utilizing the same techniques, and in the same seasons as in past years.

BCI Mammal Census: Publications Based on Research Funded by the ESP

Muller-Landau, H. C., R. Nathan, S.J. Wright, J. Giacalone-Willis, O. Calderon, G. Willis, S. P. Hubbell, R. Condit, R. B. Foster.  2001.  Patterns and causes of interannual variation in seed dispersal among tropical trees.

Glanz, W., R.Thorington, J. Giacalone-Madden, and L. Heaney.  1982.  Seasonal Food Use and Demographic Trends in Sciurus granatensis.  In:  E. Leigh, Jr. (ed.) The Ecology of a Tropical Forest.  Washington, DC:  Smithsonian Institution Press.

Giacalone-Madden, J., W. Glanz, and E.Leigh, Jr.  1990.  Adicion: Fluctuationes poblacionales a largo plazo de Sciurus granatensis en relacion con la desponsibilidad de frutos.  In:  E. Leigh, Jr. (ed) Ecologia de un Bosque Tropical.  Balboa, Panama:  Smithsonian Tropical Research Institute.

Moreno, Ricardo and Jacalyn Giacalone.  2002 (in Prep).  Ecology and Behavior of Ocelots on Barro Colorado Island, Panama. For a detailed description of some of mammals studied on BCI

For a list of mammal species (not including bats) on BCI click here, or click here

For a list of bats species on BCI click here

For mammal photos click here