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Yu, N. and D.A. Culver, 1999. In Situ Survival and Growth of Zebra Mussels
(Dreissena polymorpha) Under Chronic Hypoxia in a Stratified
Lake, National Marine Fisheries Service, NOAA.
Reprinted from Hydrobiologia (1999) 392(2): 205-215, with kind
permission from Springer Science and Business Media
In Situ Survival and Growth of Zebra Mussels (Dreissena polymorpha) Under Chronic Hypoxia in a Stratified Lake
Abstract
Experiments and field surveys were conducted in Hargus Lake (Ohio, U.S.) to investigate the effect of lake stratification on the survival, growth and distribution of zebra mussels. During the lake
stratification period, relatively stable temperature and dissolved oxygen (DO) gradients persisted
across the water column, allowing us to examine the chronic effect of hypoxia on zebra mussels.
Zebra mussels were incubated in cages and suspended at different depths in the water column at
both pelagic (max. depth = 12 m) and littoral (max. depth = 3.5 m) sites from April 18 to September
28, 1994. No mussel survived to the end of the experiment in cages greater than or equal to 5.5 m,
whereas the highest survival rate (76%) occurred at 5 m depth where temperature and DO
remained fairly stable for at least 3 months. The threshold oxygen level for survival was between
1.0-1 .7 mg 1(-1) when water temperature was at about 17-18 degrees C. While zebra mussels'
survival rate was not affected under the sublethal hypoxic conditions, their growth was greatly
retarded by poor water quality. The field survey showed that the zebra mussels and macrophytes
had about the same distribution and their biomasses were positively related. The percentage of
mussels in aggregates increased towards their maximum distribution depth. The maximum
distribution depth of the naturally occurring zebra mussels was only 2.8 m, whereas the adult
mussels could survive the entire stratification period when being artificially placed on the 3.5 m
bottom, and young mussels could colonize the 3.5 m bottom if solid substrates were provided. We
conclude that lack of substrate, rather than hypoxia, was the limiting factor of zebra mussel distribution above 5 m depth in Hargus Lake.
Contact: Neng Yu, National Marine Fisheries Service, NOAA, Office of Habitat Conservation, 1315 East-West Highway, Silver Spring, MD 20910
Key Words: Zebra_mussel, Basic_biology,
Colonization
Product Type: Research, Basic_biology
User Type: General
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