Population structure and movement of Monito del Monte (Dromiciops gliroides Thomas 1894)

RIVAROLA, MD; AMICO, GC; CARLO, T; MORALES, JM

Mendoza, Argentina

Congreso; The 10 th International Mammalogical congress; 2009

The marsupial Dromiciops gliroides is endemic to the northern portion of the temperate forests in southern South America. It is an arboreal and nocturnal marsupial associated with Nothofagus forest. The objective of the present study is to determine the population structure of D. gliroides and the relationship between individual characteristic (sex and age) with animal movement. The study was conducted at Llao-Llao in Bariloche, Argentina during the summer 2009 (January-April). Two square grids were established 150 m apart. Each grid consisted of 25 live-traps (Tomahawk-style) placed 1-2 m above ground and spaced at 10 m intervals covering an area of 50 x 50 m. Traps were run over four consecutive nights each month. Traps were checked daily and all captured marsupials were measured (weigh, total length, tail length and tail basal perimeter), and their sex and age recorded. Before releasing the animals at the point of captured they were fitted whit PIT-tags (Biomark, USA). Also, total of 28 individuals were fitted with glue-on VHF radio transmitter (ATS, USA). Radio-tracking sessions were carried out during days and nights using triangulation from different fixed stations. During the whole season 73 individuals were caught: 35.6% juveniles and 64.4% adults, whit 66% of males and 34% of females. The percentage of recapture was near 50% in both sites. Most recaptures occurred in the same grid were previously captured and liberated. Few individuals moved across both sampling grids. Overall, our results suggest that Dromiciops has strong site fidelity but it is capable of performing larger-scale forays.