INVESTIGADORES
NOVARO Andres Jose
artículos
Título:
Evaluation of a fecal-pellet index of abundance for mountain vizcachas (Lagidium viscacia) in Patagonia.
Autor/es:
WALKER, R.S.; V. PANCOTTO; J. SCHACHTER-BROIDE; G. ACKERMANN; NOVARO, A.J.
Revista:
MASTOZOOLOGÃA NEOTROPICAL
Editorial:
UNIDAD DE ZOOLOGÍA Y ECOLOGÍA ANIMAL, INSTITUTO ARGENTINO DE INVESTIGACIÓN DE LAS ZONAS ARIDAS, CRICYT, CONICET
Referencias:
Año: 2000 vol. 7 p. 89 - 94
ISSN:
0327-9383
Resumen:
We present an index of abundance based on fecal-pellet counts for mountain
vizcachas (Lagidium viscacia) in the Patagonian steppe. We use regression to calibrate the
index to size of populations of mountain vizcachas estimated by captures and intensive
observations at seven sites. By obtaining index values on two different occasions and comparing
the regressions for these two occasions, we determine that this is a valid constantproportion
index under the conditions of our study. The use of this index should be limited
to populations of mountain vizcachas inhabiting low, vertical cliffs. Its use outside the study
area requires the assumption that local conditions do not affect the relationship between the
number of piles of pellets and the number of mountain vizcachas which we found in our study
area. We advise that a validation study be done locally wherever the index is to be used.
If this is not possible, the index should be used to compare relative rather than absolute
abundance, and results should be interpreted with caution.