Dynamique de Population chez Trois Marsupiaux Didelphides de Guyane

Abstract

Five species of Didelphid marsupials were trapped live, marked, and relesed in a secondary forest in French Guiana during a 26-mo field study. Data on body weight, body length, dental stage, and reproductive state of females were collected. A total of 851 individuals, including 372 pouch-young, were monitored in 2273 captures. This abundance of data we made led us to a comparative analysis of the population dynamics of three species: Didelphis marsupialis, Philander opossum, and Caluromys philander, which represented 94 percent of the whole captures. Some data on the two other species, Marmosa murina and M. ceinerea, were added for comparison. These sympatric Didelphids are nocturnal, with a basically frugivorous and insectivorous diet. The three main species have high densities, high reproductive rates, short life-spans, and rapid population turnover. There are some differences in these parameters, mainly between the arboreal species, C. philander, and both terrestrial species, D. marsupialis and P. oppossum. Although all have few social interactions and show a lack of territoriality, C. philander appear to have a longer life-span, a lower reproductive rate and a more sedentary population. M. cinerea were very rare in this area, whereas M. murina show large density variation.