Snail-smashing by Thekla Lark, Galerida theklae, on Otala lactea: foraging behaviour and prey selection.

Full article

Published:

Volume 38(2), December 1991. Pages 297-303.

Language:

Spanish

Original title:

La Cogujada Montesina, Galerida theklae, como depredador del caracol Otala lactea: comportamiento alimenticio y selección de presa

Keywords:

Galerida theklae, Otala lactea, behaviour, predation, prey selection, shrubsteppe.

Abstract:

The feeding behavior of Thekla lark (Galerida theklae) on snails of the species Otala lactea was studied. Thekla larks get rid of snails shells by smashing them against small stones prior to eating, in a similar way to the technique used by Turdus phllomelos. They carry out a selective predation on smaller snails, although both snail pigmentation morphs present in the area are consumed in the same frequencies. This size-selection and the observation of a lack of predation on other medium or big-sized snail species frequent in the area (Sphinterochila candidisima and Iberus alonensis) seem to support the idea that selective feeding responds to shell hardness. This feature may also be responsible for the fact that other steppe do not use this trophic source as well.