To continue an inventory of freshwater Oligochaeta (Annelida)
To continue an inventory of freshwater Oligochaeta (Annelida)
Aquatic oligochaetes represent the most diverse, widely distributed group of segmented worms (Phylum Annelida) in freshwater habitats in North America . Over 200 species of freshwater oligochaetes (13 families, 75+ genera) occur in North America ; no published papers, however, have addressed the biodiversity of aquatic oligochaetes in the Great Smoky Mountains National Park . Our research on the distribution of oligochaetes in the Park (1999 through 2003) has been supported, in part, by annual mini-grants from Discover Life In America, Inc. The website: < http://www.inhs.uiuc.edu/~mjwetzel/AOGSMNP.home.html > summarizes results of our research to date, including georeferenced locality information for 112 sites; methodologies; list of species occurring regionally; species collected in the Park during this research; funding; pertinent literature, presentations and publications; and public outreach opportunities aligning this research with the ATBI Science Plan. Funding in 2004 will support continuing surveys for oligochaetes in the Park, concentrating on low gradient streams, springs, and wetland habitats. Crayfishes will be collected to obtain branchiobdellidans (worms on crayfishes that are related to oligochaetes) in anticipation of funding from the National Science Foundation to study the taxonomy and distribution of these worms – those occurring in the Park, and elsewhere in the world, leading to a monograph on this group.
Results of research. Prior to 2004, 20 species of oligochaetes representing 4 families and 14 genera had been documented from aquatic habitats in the Park (collections from 1999 through 2003). At the time of collection and identification, all oligochaete species (excepting one) represented new records for the Park, and several species represented new state records for Tennessee and/or North Carolina; these records were noted in our 2002 publications (Wetzel and Morgan 2002a, 2002b), and (with updates) presented in our recent paper (Wetzel and Morgan 2007) in the special issue of Southeastern Naturalist, which focused on the ATBI program in the GSMNP. That summary is the result of identifications of over 3,000 slide-mounted specimens. Several as-yet undocumented genera and species are represented by immature (and thus unidentifiable) specimens.
Over 1,500 oligochaete specimens were collected and identified from 25 sites sampled during 2004. Ten species previously unreported from our previous surveys were identified from these collections (preceded by a buch of these newly discovered species in the Park may also represent new state records for North Carolina and/or Tennessee, but I must first review published records and those in my filed to document this more accurately.
The field methodologies used during this 2004 study to collect aquatic oligochaetes [summarized here:
http://www.inhs.uiuc.edu/~mjwetzel/AOGSMNP.fldmeth.html ] inherently result in the collection of detritus and other organic and inorganic matter present at each site; an extensive diversity of other macroinvertebrate fauna associated with this material is thus also collected. Although elutriation of samples at the site immediately after collection reduces the amount of material in the samples returned to the lab for processing, much effort (tedious and time-consuming) is required in the laboratory to sort small oligochaete specimens from the detritus, and to sort and label the numerous other macroinvertebrates for other researchers. While these efforts (processing the non-oligochaete specimens) ‘dilute’ the effort that could be focused exclusively on the annelid fauna present in the samples, these other macroinvertebrates document distributional information for species and populations in the Park – information that may not be realized until interested taxonomists and systematists for many of these groups can set aside time for completing identifications of these specimens. As noted below [“Transfer of non-annelid aquatic macroinvertebrates”], numerous specimens already have been transferred to specialists working in the Park on several of these groups.
