Files in this item



application/pdf8600210.PDF (5MB)Restricted to U of Illinois
(no description provided)PDF


Title:Seed Dispersal by Fall Migrant Frugivorous Birds in an East-Central Illinois Woodland (Treefall Gap)
Author(s):Hoppes, William Gary
Department / Program:Ecology, Evolution, and Conservation Biology
Discipline:Ecology, Evolution, and Conservation Biology
Degree Granting Institution:University of Illinois at Urbana-Champaign
Subject(s):Biology, Ecology
Abstract:I investigated patterns of seedfall, avian frugivore pre- and post-foraging behavior, and seed germination and seedling success for several species of bird-dispersed plants in an east-central Illinois deciduous woodland. Using seed traps and a combination of natural and artificial fruit displays, I found that small seeds were dispersed by birds farther, on average, than large seeds and that small seeds had a much greater probability of being dispersed into treefall gaps than large seeds. I also found that based on the relative area of each habitat, seedfall was much higher than expected in treefall gaps, the best growing sites for seeds, than in undisturbed forest. By following the pre- and post-foraging movements of frugivores, I found that, after eating fruit, canopy frugivores left fruiting plants at a higher rate of speed than did understory frugivores. Canopy frugivores also had a higher probability of depositing seeds in treefall gaps than did understory frugivores. Finally, by mapping the seed germination and seedling survival patterns for seven species of bird-dispersed plants in a 150 x 150 m section of the woodland and following seedling success over the next four years, I was able to test three hypotheses concerning the advantages to adult plants of avian dispersal of seeds. Results for two species supported the Colonization Hypothesis; results from four species supported the Directed-dispersal Hypothesis; but no species supported the Escape Hypothesis. I was unable to explain the results of one species in the context of any of the hypotheses.
Issue Date:1985
Description:160 p.
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1985.
Other Identifier(s):(UMI)AAI8600210
Date Available in IDEALS:2015-05-14
Date Deposited:1985

This item appears in the following Collection(s)

Item Statistics