Bark consumption of creosote bush (Larrea cuneifolia) by cuises (Microcavia australis): effect on branch survival and reproduction

CAMPOS, CLAUDIA; C. E. BORGHI; S. M. GIANNONI; A MANGEAUD; TOGNELLI, MF

ECOLOGÍA AUSTRAL

Año: 2006 vol. 16 p. 1 - 6

0327-5477

Locally, mammalian herbivores may have significant effects on the abundance and fitness of plant species. This study focuses on the interaction between cuises (Microcavia australis –Rodentia-) and creosote bush (Larrea cuneifolia –Zygophyllacea-), which is a widespread and ecologically dominant evergreen shrub in the Monte Desert of Argentina. Specifically, we examined the probability of plants being gnawed by cuises in relation to branch diameter and distance to cuis colonies. Additionally, we assessed the effect of gnawing by cuises on branch condition, production of flowers and fruits and branch survival. In general, gnawing by cuises negatively affects creosote bush plants. The likelihood of being gnawed is higher for branches of smaller diameter and in plants growing closer to cuis colonies. Also, cuises significantly affect the condition, production of reproductive structures and survival of creosote bush branches. This, in turn, may have a long-term effect on the spatial distribution of creosote bush plants in this ecosystem