HR: 09:30h
AN: NB21B-05    [Abstracts]
TI: Neotropical Amphibian Declines Affect Stream Ecosystem Properties
AU: * Connelly, S
EM: scottcon@uga.edu
AF: Institute of Ecology, University of Georgia, Athens, Ga 30602 United States
AU: Pringle, C M
EM: cpringle@uga.edu
AF: Institute of Ecology, University of Georgia, Athens, Ga 30602 United States
AU: Bixby, R J
EM: bbixby@uga.edu
AF: Institute of Ecology, University of Georgia, Athens, Ga 30602 United States
AU: Whiles, M R
EM: mwhiles@zoology.siu.edu
AF: Department of Zoology, Southern Illinois University, Carbondale, IL 62901 United States
AU: Lips, K R
EM: klips@zoology.siu.edu
AF: Department of Zoology, Southern Illinois University, Carbondale, IL 62901 United States
AU: Brenes, R
EM: tadpole@siu.edu
AF: Department of Zoology, Southern Illinois University, Carbondale, IL 62901 United States
AU: Colon-Gaud, J C
EM: checo@siu.edu
AF: Department of Zoology, Southern Illinois University, Carbondale, IL 62901 United States
AU: Kilham, S
EM: kilhams@drexel.edu
AF: Department of Bioscience and Biotechnology, Drexel University, Philadelphia, PA 19104 United States
AU: Hunte-Brown, M
EM: meshagae@drexel.edu
AF: Department of Bioscience and Biotechnology, Drexel University, Philadelphia, PA 19104 United States
AB: Global declines of amphibians are well documented, yet effects of these dramatic losses on ecosystem structure and function are poorly understood. As part of a larger collaborative project, we compared two upland Panamanian streams. Both streams are biologically and geologically similar; however, one stream (Fortuna) has recently experienced almost complete extirpation of stream-dwelling frogs, while the other (Cope) still has intact populations. We experimentally excluded tadpoles from localized areas in each stream. We then compared chlorophyll a, algal community composition, ash-free dry mass (AFDM), inorganic matter, and insect assemblages in control and exclusion areas. Additionally, we sampled the natural substrate of both streams monthly for chlorophyll a, algal community composition, AFDM, and inorganic matter. At Cope, chlorophyll a, AFDM, and inorganic matter were greater in areas where tadpoles were excluded than in their presence. Numbers of dominant algal species (e.g., Nupela praecipua and Eunotia siolii) were greater in the exclusion versus control treatments. Monthly sampling of natural substrate indicated higher chlorophyll a and AFDM at Cope compared to Fortuna. Our data suggest that stream-dwelling anuran larvae have significant impacts on algal communities. These results also have implications for predicting the relevance of short-term experimental manipulations to long-term, whole-stream processes.
DE: 9810 New fields (not classifiable under other headings)
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly