Tuesday, June 5, 2007 - 11:45 AM
127

Parks and Preserves as Refuges for Stoneflies (Plecoptera) in Indiana and Illinois

R. Edward DeWalt1, Donald W. Webb1, and Scott A. Grubbs2. (1) Illinois Natural History Survey, 1816 S Oak St., Champaign, IL 61820, (2) Biological Sciences, Western Kentucky University, Bowling Green, KY 42101

The presence of a large number of pre-1950 stonefly specimens at the Illinois Natural History Survey, the Canadian National Collection, and the Purdue University Entomology Collection, among others allowed for comparison of recent collection efforts at state parks and preserves in glaciated Illinois and Indiana. Parks and preserves protecting deep ravine habitats have retained the greatest number of stonefly species. Within these systems, losses were greatest with increasing longitude as preserves became more isolated from presumed glacial refugia in the southeastern USA.  Larger streams are not well protected by parks and preserves, probably due to the preponderance of their drainages being unprotected and surrounded by agricultural or urban areas. These systems were historically dominated by large Perlidae and Perlodidae stoneflies with direct egg hatch and prolonged nymphal exposures (11 to 23 months or more) that put them at extreme risk of local extinction. Most large, predatory, direct egg hatch, long life cycle species have been extirpated from small and large rivers throughout the region. These losses probably reflect what is happening to mayflies, caddisflies, and odonates in the region and suggest that a reassessment of public land systems used for preserving aquatic habitat is warranted.

See more of Conservation Ecology
See more of Contributed Sessions

See more of The NABS 55th Annual Meeting