IADIZA   20886
INSTITUTO ARGENTINO DE INVESTIGACIONES DE LAS ZONAS ARIDAS
Unidad Ejecutora - UE
artículos
Título:
Diet of a fossorial rodent (Octodontidae), above ground food availability, and changes related to cattle grazing in the Central Monte (Argentina).
Autor/es:
ROSI; PUIG, S.; CONA, M.I.; VIDELA, F.; MÉNDEZ, E.; ROIG, V.G.
Revista:
JOURNAL OF ARID ENVIRONMENTS
Editorial:
ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD
Referencias:
Año: 2009 vol. 73 p. 273 - 279
ISSN:
0140-1963
Resumen:
Overgrazing by livestock has caused desertification in the Monte, where ctenomyids and livestock share grasses as main food items. The diet of Ctenomys eremophilus, above-ground food availability and changes related to cattle grazing are analyzed in the aridplain of Mendoza, Argentina. The most available categories were grasses, followedby low shrubs and tall shrubs. Tuco-tucos showed dietary generalism, ate mainly above-ground plant parts, preferred grasses and avoided shrubs at both grazed and ungrazed sites. Plant cover, grass diversity and availability decreased under livestockgrazing, which was reflected in the diet by a lower percentage of grasses, a shift toward low shrubs and higher number of frequently used resources. Tuco-tucos in the grazed paddock compensated for lower consumption of vegetative plant parts by increasing the use of Prosopis flexuosa pods stored inside burrows. Moreover, greater dietary variation among individuals suggests foraging restricted to the items closest to burrow holes. These feeding tactics would allow them to reduce above-ground foraging as a response to high raptor predation risk due to increased bare soil. The plant recovery detected during the rest period, favoured by moderate stocking rate and rotational grazing system, would allow coexistence of tuco-tucos and cattle. Key words: Feeding strategies Livestock grazing Subterranean mammals