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Horvath, T.G., G.A. Lamberti, D.M. Lodge, and W.L. Perry, 1996. Zebra
Mussel Dispersal in Lake-Stream Systems: Source-Sink Dymanics? Lake Michigan
Ecological Research Station.
Reprinted from Journal of the North American Benthological Society
(1996) 15(4): 564-575
Zebra Mussel Dispersal in Lake-Stream Systems:
Source-Sink Dymanics?
Abstract
We investigated the ability of zebra mussels (Dreissena polymorpha) to colonize small streams (<30 m wide), which have been considered to have
low susceptibility to invasion. We examined European literature concerning riverine mussel populations and sampled lake and stream sites in the St.
Joseph River basin (Indiana-Michigan, USA) for mussels. The presence of colonized upstream lakes (rather than stream size) was the critical
watershed feature determining zebra mussel invasion of streams because such lakes served as a source of veligers that drifted into outflowing streams.
For all sites, there was a significant positive association (p < 0.001) between zebra mussel presence in lakes and in their outflowing streams. Two
streams in the St. Joseph River basin (average widths 20 m and 7 m) had mussel densities that declined exponentially from >1000/m2 at the lake
outlet to about 10/m2 within 1 km downstream of the colonized take, although isolated mussels were found up to 12 km downstream. This pattern
persisted for 3 y (1993-1995) with no substantial change in mussel distribution or abundance. Stream populations appear not to be
self-sustaining, but rather they rely on an upstream source of larvae. Our findings suggest that zebra mussel distributions in flowing water ecosystems
are best described by a source-sink model, wherein streams (''sinks'') are the recipient for larval mussels produced in lakes (''sources'').
Entire Paper
Contact: Thomas Horvath, Lake Michigan Ecological
Research Station, 1100 N. Mineral Springs RoadPorter,
MI 46304
Keywords: Zebra_mussel, Colonization,
Monitoring, Environmental_impacts
Product Type: Research,
Impact
User Type: General
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