Bats and moths contribute to the reproductive success of the columnar cactus Pilosocereus leucocephalus

Abstract

The pollination systems of columnar cacti in the dry tropics are often thought to be highly specialized to bats. This specialization is generally inferred when flowers that are only exposed to the activity of nocturnal visitors set fruit and seed. Although moths are also common visitors to the flowers of columnar cacti at night, it is generally thought that their contribution to the reproductive success of this cactus is negligible. Using selective exclusions, we assessed the contribution of bats and moths to the reproductive success in a population of Pilosocereus leucocephalus in central Mexico. Fruit set was 100% for bat-pollinated flowers and 34% in moth-pollinated flowers. Seed number per fruit was 1473 in bat-pollinated and 836 in moth pollinated flowers. Our results clearly show that in addition to bats, moths are effective pollinators of Pilosocereus leucocephalus in the study area. Therefore, bats are the main pollinators of P. leucocephalus, and moths are the secondary pollinators.