HR: 09:30h
AN: NB41F-05 INVITED     [Abstracts]
TI: Diversity and Life Histories in Freshwater Mussel Communities of the Gulf Coastal Plain, USA
AU: * Haag, W R
EM: whaag@fs.fed.us
AF: USDA Forest Service, Center for Bottomland Hardwoods Research, 1000 Front Street, Oxford, MS 38655 United States
AU: Warren, M L
EM: mwarren01@fs.fed.us
AF: USDA Forest Service, Center for Bottomland Hardwoods Research, 1000 Front Street, Oxford, MS 38655 United States
AB: The Gulf Coastal Plain supports a diverse mussel fauna including many endemic species. Richness among drainages was associated strongly and positively with watershed size. Assemblage similarity among drainages identified three major faunal groupings: Pontchartrain-Pearl-Pascagoula-Mobile; Escambia-Choctawhatchee; and Apalachicola-Ochlockonee-Suwannee. The Escambia-Choctawhatchee showed greater affinity to the Apalachicola than to the Mobile Basin. Patterns of mussel assemblages among drainages were associated strongly with fish assemblages suggesting two non-mutually exclusive hypotheses: 1) biogeographic history affected both groups similarly, and 2) the fish host relationship was important in shaping mussel communities. Based on interspecific variation in life history traits including host use, longevity, offspring size, and fecundity, we established seven guilds to represent regional diversity in life history strategies. The number of guilds decreased from west to east indicating reduced ecological complexity. For widely represented guilds, drainages showed either 1) similar guild composition because of replacement by ecologically similar species, or 2) a shift in dominance among guilds along a west-east continuum. This dichotomy cannot be reconciled currently because data are lacking for numerous species of Elliptio, a dominant genus in eastern Gulf Coastal Plain mussel communities. This information gap illustrates the abundant opportunities for ecological research in the region.
DE: 9810 New fields (not classifiable under other headings)
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly