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Seed dispersal and predation by Proechimys semispinosus and Sciurus granatensis in gaps and understorey in central Panama

Published online by Cambridge University Press:  01 September 2008

Alejandra Carvajal
Affiliation:
Department of Biology and Microbiology, University of Wisconsin – Oshkosh, 800 Algoma Blvd, Oshkosh WI 54901, USA Present address: Department of Biology, Castetter Hall 167A, MSC03 2020, 1 University of New Mexico, Albuquerque, NM 87131-0001, USA.
Gregory H. Adler*
Affiliation:
Department of Biology and Microbiology, University of Wisconsin – Oshkosh, 800 Algoma Blvd, Oshkosh WI 54901, USA
*
2Corresponding author. Email: adler@uwosh.edu

Abstract:

Seed dispersal and predation by spiny rats (Proechimys semispinosus) and red-tailed squirrels (Sciurus granatensis) were studied in five forest gaps and adjacent forest understorey on Barro Colorado Island, Panama, during June and July 2003 and January 2004. Live trapping on grids was used to estimate the abundances of rats in both habitats and was conducted during 10 nights at the beginning of each field season. We captured 70 individual spiny rats (53 in forest gaps and 17 in understorey). To address the removal and dispersal of seeds, semi-permeable wire-mesh exclosures were set at randomly selected stations within the trapping grids. These exclosures allowed the entry of spiny rats, squirrels, and other small rodents but excluded larger granivorous mammals. Seeds were marked with pieces of string that were dusted with fluorescent powder and tracked at night with an ultraviolet light. A total of 304 seeds was removed (159 in forest gaps and 145 in understorey). Spiny rats removed more seeds from gaps, and squirrels removed more seeds from understorey. Both species dispersed more seeds during the rainy season than during the dry season. Squirrels dispersed seeds farther than did spiny rats. Due to their foraging behaviour and association with gaps, spiny rats may disperse seeds from forest understorey into gaps.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2008

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References

LITERATURE CITED

ADLER, G. H. 1995. Fruit and seed exploitation by Central American spiny rats, Proechimys semispinosus. Studies on Neotropical Fauna and Environment 30:237244.CrossRefGoogle Scholar
ADLER, G. H. 2000. Tropical tree diversity, forest structure and the demography of a frugivorous rodent, the spiny rat (Proechimys semispinosus). Journal of Zoology 250:5774.Google Scholar
ADLER, G. H. & KESTELL, D. W. 1998. Fates of Neotropical tree seeds influenced by spiny rats (Proechimys semispinosus). Biotropica 30:677681.CrossRefGoogle Scholar
ADLER, G. H. & LAMBERT, T. D. 2008. Spatial and temporal variation in fruiting phenology of palms in isolated stands. Plant Species Biology 23:917.CrossRefGoogle Scholar
ADLER, G. H. & SEAMON, J. O. 1991. Distribution and abundance of a tropical rodent, the spiny rat, on islands in Panama. Journal of Tropical Ecology 7:349360.CrossRefGoogle Scholar
ARAUS, J. L. & HOGAN, K. P. 1994. Leaf structure and patterns of photoinhibition in two neotropical palms in clearings and forest understory during the dry season. American Journal of Botany 81:726738.CrossRefGoogle Scholar
ASQUITH, N. M. & MEJÍA-CHANG, M. 2005. Mammals, edge effects, and the loss of tropical forest diversity. Ecology 86:379390.CrossRefGoogle Scholar
ASQUITH, N. M., WRIGHT, S. J. & CLAUSS, M. J. 1997. Does mammal community composition control seedling recruitment in Neotropical forests? Evidence from Panama. Ecology 78:941946.CrossRefGoogle Scholar
AUGSPURGER, C. K. 1983. Seed dispersal of the tropical tree, Platypodium elegans, and the escape of its seedlings from fungal pathogens. Journal of Ecology 71:759771.Google Scholar
AUGSPURGER, C. K. 1984. Seedling survival of tropical tree species: interactions of dispersal distance, light-gaps, and pathogens. Ecology 65:17051712.Google Scholar
AUGSPURGER, C. K. & KELLY, C. K. 1984. Pathogen mortality of tropical tree seedlings: experimental studies of the effects of dispersal distance, seedling density, and light conditions. Oecologia 61:211217.CrossRefGoogle ScholarPubMed
BECK, H. & TERBORGH, J. 2002. Groves vs. isolates: how spatial aggregation of Astrocaryum murumuru palms affects seed removal. Journal of Tropical Ecology 18:275288.CrossRefGoogle Scholar
BECK, H., GAINES, M. S., HINES, J. E. & NICHOLS, J. D. 2004. Comparative dynamics of small mammal populations in treefall gaps and surrounding understorey within Amazonian rainforest. Oikos 106:2738.Google Scholar
BRADFORD, D. F. & SMITH, C. C. 1977. Seed predation and seed number in Scheelea palm fruits. Ecology 58:667673.CrossRefGoogle Scholar
BREWER, S. W. & REJMÁNEK, M. 1999. Small rodents as significant dispersers of tree seeds in a Neotropical forest. Journal of Vegetation Science 10:165174.Google Scholar
BREWER, S. W., REJMÁNEK, M., JOHNSTONE, E. E. & CARO, T. M. 1997. Top-down control in tropical forests. Biotropica 29:364367.CrossRefGoogle Scholar
CLARK, D. A. & CLARK, D. B. 1984. Spacing dynamics of a tropical rain forest tree: evaluation of the Janzen-Connell model. American Naturalist 124:769788.CrossRefGoogle Scholar
CLARK, D. B. & CLARK, D. A. 1987. Population biology and microhabitat distribution of Dipteryx panamensis, a neotropical fain forest emergent tree. Biotropica 19:236244.CrossRefGoogle Scholar
CONNELL, J. H. 1971. On the role of natural enemies in preventing competitive exclusion in some marine animals and in rain forest trees. Pp. 298312 in den Boer, P. J. & Gradwell, G. (eds.). Dynamics of numbers in populations. Center for Agricultural Publication and Documentation, Wageningen.Google Scholar
CROAT, T. B. 1978. Flora of Barro Colorado Island. Stanford University Press, Stanford. 943 pp.Google Scholar
DE STEVEN, D. 1988. Light gaps and long-term seedling performance of a Neotropical canopy tree (Dipteryx panamensis, Leguminosae). Journal of Tropical Ecology 4:407411.CrossRefGoogle Scholar
DE STEVEN, D. & PUTZ, F. E. 1984. Impact of mammals on early recruitment of a tropical canopy tree, Dipteryx panamensis, in Panama. Oikos 43:207216.Google Scholar
DE STEVEN, D., WINDSOR, D. M., PUTZ, F. E. & DELEON, B. 1987. Vegetative and reproductive phenologies of a palm assemblage in Panama. Biotropica 19:342356.CrossRefGoogle Scholar
DENSLOW, J. S. 1987. Tropical rainforest gaps and tree species diversity. Annual Review of Ecology and Systematics 18:431451.CrossRefGoogle Scholar
EISENBERG, J. F. 1989. Mammals of the Neotropics: the northern Neotropics. University of Chicago Press, Chicago. 449 pp.Google Scholar
EMMONS, L. H. 1982. Ecology of Proechimys (Rodentia, Echimyidae) in southeastern Peru. Tropical Ecology 23:280290.Google Scholar
EMMONS, L. H. & FEER, F. 1997. Neotropical rainforest mammals. a field guide. (Second edition). University of Chicago Press, Chicago. 396 pp.Google Scholar
FORGET, P.-M. 1990. Seed dispersal of Vouacapoua americana (Caesalpiniaceae) by caviomorph rodents in French Guiana. Journal of Tropical Ecology 6:459468.CrossRefGoogle Scholar
FORGET, P.-M. 1991a. Scatterhoarding of Astrocaryum paramaca by Proechimys in French Guiana: comparison with Myoprocta exilis. Tropical Ecology 32:155167.Google Scholar
FORGET, P.-M. 1991b. Comparative recruitment patterns of two non-pioneer canopy tree species in French Guiana. Oecologia 85:434439.CrossRefGoogle ScholarPubMed
FORGET, P.-M. 1993. Post-dispersal predation and scatterhoarding of Dipteryx panamensis (Papilionaceae) seeds by rodents in Panama. Oecologia 94:255261.CrossRefGoogle ScholarPubMed
FORGET, P.-M. 1996. Removal of seeds of Carapa procera (Meliaceae) by rodents and their fate in rainforest in French Guiana. Journal of Tropical Ecology 12:751761.CrossRefGoogle Scholar
FORGET, P.-M. & MILLERON, T. 1991. Evidence for secondary seed dispersal by rodents in Panama. Oecologia 87:596599.CrossRefGoogle ScholarPubMed
FORGET, P.-M., MUNOZ, E. & LEIGH, E. G. 1994. Predation by rodents and bruchid beetles on seeds of Scheelea palms on Barro Colorado Island, Panama. Biotropica 25:420426.CrossRefGoogle Scholar
FOSTER, R. B. 1996. The seasonal rhythm of fruitfall on Barro Colorado Island: Censuses and long-term changes. Pp. 151172 in Leigh, E. G., Rand, A. S. & Windsor, D. M. (eds.). The ecology of a tropical forest: seasonal rhythms and long-term changes. Smithsonian Institution Press, Washington.Google Scholar
GLANZ, W. E. 1984. Food and habitat use by two sympatric Sciurus species in central Panama. Journal of Mammalogy 65:342347.CrossRefGoogle Scholar
GLANZ, W. E., THORINGTON, R. W., GIACALONE-MADDEN, J. & HEANEY, L. R. 1996. Seasonal food use and demographic trends in Sciurus granatensis. Pp. 239252 in Leigh, E. G., Rand, A. S. & Windsor, D. M. (eds.). The ecology of a tropical forest: seasonal rhythms and long-term changes. Smithsonian Institution Press, Washington.Google Scholar
GUIMARÃES, P. R., LOPES, P. F. M., LYRA, M. L. & MURIEL, A. P. 2005. Fleshy pulp enhances the location of Syagrus romanzoffiana (Arecaceae) fruits by seed-dispersing rodents in an Atlantic forest in south-eastern Brazil. Journal of Tropical Ecology 21:109112.CrossRefGoogle Scholar
HEANEY, L. R. & THORINGTON, R. W. 1978. Ecology of Neotropical red-tailed squirrels, Sciurus granatensis, in the Panama Canal Zone. Journal of Mammalogy 59:846851.CrossRefGoogle Scholar
HOCH, G. A. & ADLER, G. H. 1997. Removal of black palm (Astrocaryum standleyanum) seeds by spiny rats (Proechimys semispinosus). Journal of Tropical Ecology 13:5158.CrossRefGoogle Scholar
HOGAN, K. P. 1988. Photosynthesis in two neotropical palm species. Functional Ecology 2:371377.CrossRefGoogle Scholar
HOLL, K. D. & LULOW, M. E. 1997. Effects of species, habitat, and distance from edge on post-dispersal seed predation in a tropical rainforest. Biotropica 29:459468.CrossRefGoogle Scholar
JANSEN, P. A., BONGERS, F. & HEMERIK, L. 2004. Seed mass and mast seeding enhance dispersal by a neotropical scatter-hoarding rodent. Ecological Monographs 74:569589.Google Scholar
JANZEN, D. H. 1970. Herbivores and the number of tree species in tropical forests. American Naturalist 104:501528.CrossRefGoogle Scholar
LAMBERT, T. D. & ADLER, G. H. 2000. Microhabitat use by a tropical forest rodent, Proechimys semispinosus, in Central Panama. Journal of Mammalogy 81:7076.2.0.CO;2>CrossRefGoogle Scholar
LARSON, D. & HOWE, H. F. 1987. Dispersal and destruction of Virola surinamensis seeds by agoutis: appearance and reality. Journal of Mammalogy 68:859860.CrossRefGoogle Scholar
LEIGH, E. G. 1999. Tropical forest ecology. A view from Barro Colorado Island. Oxford University Press, New York. 245 pp.CrossRefGoogle Scholar
LINDSEY, J. K. 1995. Modelling frequency and count data. Clarendon Press, Oxford. 291 pp.Google Scholar
RAND, A. S. & RAND, W. M. 1996. Variation in rainfall on Barro Colorado Island. Pp. 4759 in Leigh, E. G. Jr., Rand, A. S. and Windsor, D. M. (eds.) The ecology of a tropical forest. Seasonal rhythms and long-term changes. Second edition. Smithsonian Institution Press, Washington, D.C., USA.Google Scholar
REID, F. A. 1997. A field guide to the mammals of Central America and southeast Mexico. Oxford University Press, Oxford. 334 pp.Google Scholar
SCHUPP, E. W., HOWE, H. F., AUGSPURGER, C. K. & LEVEY, D. J. 1989. Arrival and survival in tropical treefall gaps. Ecology 70:562564.CrossRefGoogle Scholar
SMYTHE, N. 1986. Competition and resource partitioning in the guild of Neotropical terrestrial frugivorous mammals. Annual Review of Ecology and Systematics 17:169188.CrossRefGoogle Scholar
SMYTHE, N. 1989. Seed survival in the palm Astrocaryum standleyanum: evidence for dependence upon its seed dispersers. Biotropica 21:5056.CrossRefGoogle Scholar
TERBORGH, J. & WRIGHT, S. J. 1994. Effects of mammalian herbivores on seedling recruitment and survivorship in two Neotropical forests. Ecology 75:18291833.Google Scholar
TOMBLIN, D. C. & ADLER, G. H. 1998. Differences in habitat use between two morphologically similar tropical forest rodents. Journal of Mammalogy 79:953961.CrossRefGoogle Scholar
VANDER WALL, S. B., KUHN, K. M. & BECK, M. J. 2005. Seed survival, seed predation, and secondary dispersal. Ecology 86:801806.CrossRefGoogle Scholar
WINDSOR, D. M. 1990. Climate and moisture variability in a tropical forest: long-term records from Barro Colorado Island, Panama. Smithsonian Contributions to the Earth Sciences 29:1145.CrossRefGoogle Scholar
WRIGHT, S. J., CARRASCO, C., CALDERÓN, O. & PATON, S. 1999. The El Niño Southern Oscillation, variable fruit production, and famine in a tropical forest. Ecology 80:16321647.Google Scholar
WRIGHT, S. J. & DUBER, H. C. 2001. Poachers and forest fragmentation alter seed dispersal, seed survival, and seedling recruitment in the palm Attalea butyracea, with implications for tropical tree diversity. Biotropica 33:583595.Google Scholar