@article {1316,
	title = {Primary seed dispersal by red howler monkeys and the effect of defecation patterns on the fate of dispersed seeds},
	journal = {Biotropica},
	volume = {34},
	number = {2},
	year = {2002},
	note = {569EEBIOTROPICA},
	month = {Jun},
	pages = {261-272},
	abstract = {The effectiveness of a seed disperser depends on the quantity and quality of dispersal. The quality of dispersal depends in large part on factors that affect the post-dispersal fate of seeds, and yet this aspect of dispersal quality is rarely assessed. In the particular case of seed dispersal through endozoochory the defecation pattern produced has the potential of affecting the fate of dispersed seeds and consequently, dispersal quality and effectiveness. In this study, I assessed the effects of dung presence and dung/seed densities on seed predation by rodents and seconclary dispersal by dung beetles. In particular, I compared seed fates in clumped defecation patterns, as those produced by howler monkeys, with seed faces in scattered defecation patterns, as those produced by other frugivores. I also determined the prevalence of red howler monkeys (Alouatta seniculus) as seed dispersers at the plant community level in Central Amazonia by determining the number of species they dispersed in a 25-month period. I found chat dung presence and a-mount affected rodent and dung beetle behavior. Seed predation rates were higher when dung was present, and when it was in higher densities. The same number of seeds was buried by dung beetles, in clumped versus scattered defecation patterns, but more seeds were buried when they were inside large dung-piles versus small piles. Seed density had no effect on rodent or dung beetle behavior. Results indicate that caution should be taken when categorizing an animal as a high or low quality seed disperser before carefully examining the factors that affect the fate of dispersed seeds. Red howler monkeys dispersed the seeds of 137 species during the study period, which is the highest yet reported number for an Alouatta species, and should thus be considered highly prevalent seed dispersers at the plant community level in Central Amazonian terra firme rain forests.},
	keywords = {Alouatta, alouatta-palliata, Central Amazonia, defecation pattern, dispersal, Dung beetles, dung beetles scarabaeidae, howler monkeys, los, postdispersal, primary seed dispersal, secondary seed, seed, seed fate, tropical moist forest, tropical rain-forest},
	url = {<Go to ISI>://000176587000008},
	author = {Andresen, Ellen}
}
@article {1324,
	title = {Effects of dung and seed size on secondary dispersal, seed predation, and seedling establishment of rain forest trees},
	journal = {Oecologia},
	volume = {139},
	number = {1},
	year = {2004},
	note = {801LKOECOLOGIA},
	month = {Mar},
	pages = {45-54},
	abstract = {Seeds dispersed by tropical, arboreal mammals are usually deposited singly and without dung or in clumps of fecal material. After dispersal through defecation by mammals, most seeds are secondarily dispersed by dung beetles or consumed by rodents. These post-dispersal, plant-animal interactions are likely to interact themselves, as seeds buried by dung beetles are less likely to be found by rodents than unburied seeds. In a series of three experiments with seeds of 15 species in central Amazonia (Brazil), we determined (1) how presence and amount of dung associated with seeds influences long-term seed fate and seedling establishment, (2) how deeply dung beetles bury seeds and how burial depth affects seedling establishment, and (3) how seed size affects the interaction between seeds, dung beetles, and rodents. Our overall goal was to understand how post-dispersal plant-animal interactions determine the link between primary seed dispersal and seedling establishment. On average, 43\% of seeds surrounded by dung were buried by dung beetles, compared to 0\% of seeds not surrounded by dung (n=2,156). Seeds in dung, however, tended to be more prone than bare seeds to predation by rodents. Of seeds in dung, probability of burial was negatively related to seed size and positively related to amount of dung. Burial of seeds decreased the probability of seed predation by rodents three-fold, and increased the probability of seedling establishment two-fold. Mean burial depth was 4 cm (0.5-20 cm) and was not related to seed size, contrary to previous studies. Probability of seedling establishment was negatively correlated with burial depth and not related to seed size at 5 or 10 cm depths. These results illustrate a complex web of interactions among dung beetles, rodents, and dispersed seeds. These interactions affect the probability of seedling establishment and are themselves strongly tied to how seeds are deposited by primary dispersers. More generally, our results emphasize the importance of looking beyond a single type of plant-animal interaction (e.g., seed dispersal or seed predation) to incorporate potential effects of interacting interactions.},
	keywords = {alouatta-palliata, beetles scarabaeidae, Central Amazonia, communities, ecology, fate, horse dung, howler monkeys, los-, plant, plant-animal interactions, rain forest, recruitment, seed, tuxtlas},
	url = {<Go to ISI>://000220097200006},
	author = {Andresen, Ellen and Levey, Douglas J.}
}
