Seed predation and potential seed dispersers of the endemic, narrowly distributed Ceratozamia norstogii (Zamiaceae)

Abstract

Reproductive ecology in Ceratozamia has been little studied. In particular, very little is known about seed dispersal. Here we report the observation of seed predators and potential seed dispersers of the endemic to Mexico and narrowly distributed Ceratozamia norstogii (Zamiaceae). Camera traps were installed in front plants of Ceratozamia norstogii and also strobili phenology until their maturity and disintegration was determined. The female strobili of Ceratozamia norstogii has a development of ten months, from the time it emerges until it disintegrates. We identified four stages of strobili development: 1) emergent strobili, 2) young strobili, 3) adult strobili, and 4) mature strobili. Our results support an animal-dispersal hypothesis in Ceratozamia. Three mammals (a mouse, a southern spotted skunk and a kinkajou) were observed consuming or removing seeds of Ceratozamia norstogii. Removal and consumption of mature seeds by frugivorous occur at night. The most frequent visitor was the mouse, followed by the southern spotted skunk and the kinkajou. Significant differences (GLM, P<0.05) in visitor frequency and time for interaction were found between the kinkajou and the rest of the frugivores, but not between the mouse and the skunk. At local scales, seed dispersal by small mammals could be related to the high-density populations of several Ceratozamia species, and at larger scales, related to events of allopatry.