EFFECTS OF SEED INGESTION BY THE LESSER LONG-NOSED BAT LEPTONYCTERIS YERBABUENAE ON THE GERMINATION OF THE GIANT CACTUS ISOLATOCEREUS DUMORTIERI

摘要

Bats have been considered efficient seed dispersers of columnar cactus (Isolatocereus dumortieri). However, to date, very little is known about the effect of seed ingestion by bats on seed germination. We carried out some germination assays for seeds of the cactus I. dumortieri obtained directly from fruits and fecal clumps of the endangered lesser long-nosed bat (Leptonycteris yerbabuenae) in a semiarid zone, within the Biosphere Reserve Barranca of Metztitlan in Central Mexico. Additionally, we evaluated seed deposition patterns by bats. We found that 61.7% of the removed seeds were dispersed in fecal clumps, whereas the remaining seeds were spitted as single seeds. We also found that ingestion diminished seed germination by 65%. Under these conditions, seeds deposited individually around the mother plant may be of importance for local restoration and have the function of reforesting the locality, whereas ingested seeds can reach long distances and colonize new areas.