INVESTIGADORES
OVEJERO AGUILAR Ramiro Jose Antonio
congresos y reuniones científicas
Título:
Space use in desert environments by guanaco (Lama guanicoe). Seasonal variation is in relation with vegetal productivity.
Autor/es:
ACEBES, P. ; MALO, J.E. ; SUAREZ, F.; OVEJERO, R.; BORGHI, C.E; GIANNONI, S.M. & TRABA, J.
Reunión:
Congreso; IV World Congress on Mountain Ungulates; 2006
Resumen:
We describe seasonal variability in space and habitat use by a small population of guanaco (Lama guanicoe)
at the driest limit of its distribution. During 2005 wet- and
dry-seasons we GPS-located all guanaco observations (n=75) obtained
during systematic surveys (app. 150 hours/season) through
Ischigualasto-Talampaya World Heritage Site (Argentina). Plant
productivity for each guanaco location (in a 250m buffer) was estimated
with a Vegetation Index (V.I.) for arid sites from a LANDSAT 7 image.
Results show a high seasonal overlap for the Minimum Convex Polygons
(Cole Concordance Index >79%) but a much lower overlap for the 80%
Kernel areas (CCI <34%). Habitat use was significantly different
between seasons (chi-squared= 23.85; 9 df; p=0.0045). During wet season
guanacos selected mixed jarillal (34.3%) and zampal (20.0%), while
during dry season guanacos selected open (30.0%) and mix scrubland
(22.5%) and treelike cacti-dominated slopes (20.0%). Satellite analysis
show a concentration of guanacos on the most productive patches
(ANCOVA-test, p<0.0001), being also higher the V.I. for the locations
of larger groups (p=0.008). These results show guanaco´s flexibility in
space use and habitat selection, and its seasonal dependence on the
most productive habitats.