Effects of endozoochory and diploendozoochory by captive mammals on Juniperus deppeana seeds

Carnivorous mammals disperse seeds through endozoochory and diploendozoochory. The former consists of ingestion of the fruit, passage through the digestive tract, and expulsion of the seeds, a process that allows scarification and dispersal of the seeds over long or short distances. The latter is typical of predators that expel seeds that were contained in the prey and the effects of which may differ from those of endozoochory with respect to the retention time of the seeds in the tracts, as well as their scarification and viability. The objective of this study was to conduct an experimental evaluation comparing the capacity of each mammal species in terms of the dispersal of Juniperus deppeana seeds and, at the same time, to compare this capacity through the two dispersal systems: endozoochory and diploendozoochory. We measured dispersal capacity using indices of recovery, viability, changes in testas, and retention time of seeds in the digestive tract. Juniperus deppeana fruits were c..., An overview of the experimental evaluation is given in this first section, which comprises two main stages, and the particular details of each stage are presented separately below.
The experimental evaluation was conducted in March 2019 and consisted of two stages: I) to create the habit in mammals of ingesting J. deppeana seeds and II) the experimental evaluation of endozoochory and diploendozoochory. Prior to the two stages, the collection of seeded fruits of the plant component was carried out. The J. deppeana shrub produces globules that generally contain five seeds each, and the fruits of this species are consumed and dispersed by both birds and mammals (Livingston, 1972; Schupp et al., 1997). The animal component was also selected according to the dispersal system: gray fox, coati (omnivores), and rabbit (herbivore/feline prey) for endozoochory, and bobcat and cougar (predators) for diploendozoochory. It is documented that all selected mammals disperse seeds by either one system o...,