USGS Paleontology glossary Acritarch microscopic organic structure from any of a number of organisms; common during the Proterozoic. Adaptive radiation, evolutionary radiation the rapid expansion and diversification of a group of organisms as they fill unoccupied ecological nichesevolving into new species.
Three color varieties of the shell of the zebra mussel Close-up of a typical shell of a zebra mussel Zebra mussel and the closely related and ecologically similar quagga mussels are filter-feeding organisms. They remove particles from the water column. The zebra mussels process up to one liter of water per day, per mussel.
Nonfood particles are combined with mucus and other matter and deposited on lake floors as pseudofeces. Since the zebra mussel has become established in Lake Erie, water clarity has increased from 6 inches to up to three feet in some areas.
These plants, when decaying, wash up on shorelines, fouling beaches and cause water quality problems. This biomass becomes available to bottom-feeding species and to the fish that feed on them.
Other mussel species frequently represent the most stable objects in silty substrates, and zebra mussels attach to, and often kill these mussels. They build colonies on native unionid clams, reducing their ability to move, feed, and breed, eventually leading to their deaths.
This has led to the near extinction of the unionid clams in Lake St. Clair and the western basin of Lake Erie.
Zebra mussels also can tolerate a wide range of environmental conditions and adults can even survive out of water for about 7 days. Drawing of zebra mussel, showing the byssus Predators[ edit ] Research on natural enemies, both in Europe and North America, has focused on predators, particularly birds 36 species and fish 15 and 38 species eating veligers and attached mussels.
The vast majority of the organisms that are natural enemies in Europe are not present in North America. Ecologically similar species do exist, but these species are unlikely to be able to eliminate those mussels already established and will have a limited role in their control.
An adult crayfish consumes around zebra mussels every day, or about mussels in a season. Predation rates are significantly reduced at lower water temperatures. Fish do not seem to limit the densities of zebra mussels in European lakes.
Smallmouth bass are a predator in the zebra mussels' adopted North American Great Lakes habitat. This test was conducted in a lakefront harbor in the western province of Manitoba.
They disrupt the ecosystems by monotypic colonizationand damage harbors and waterways, ships and boats, and water treatment and power plants. Water treatment plants are most affected because the water intakes bring the microscopic free-swimming larvae directly into the facilities.
Zebra mussels also cling to pipes under the water and clog them. Grossinger reported it in Hungary in Kerney and Morton described the rapid colonization of Britain by the zebra mussel, first in Cambridgeshire in the s, London inand in the Union Canal near Edinburgh in Canals that artificially link many European waterways facilitated their early dispersal.
It is nonindigenous in the Czech Republic in the Elbe River in Bohemia since ;  in southern Moravia, it is probably native. The first appearance of the organism in northern Italy was in Lake Garda in ;  in central Italy, they appeared in Tuscany in Many water companies are reporting having problems with their water treatment plants with the mussels attaching themselves to pipeworks.
Another possible, often neglected, mode of introduction is on anchors and chains, although this has not been proven. Since adult zebra mussels can survive out of water for several days or weeks if the temperature is low and humidity is high, chain lockers provide temporary refuge for clusters of adult mussels that could easily be released when transoceanic ships drop anchor in freshwater ports.
They have become an invasive species in North America, and as such they are the target of federal policy to control them, for instance in the National Invasive Species Act Using models based on the genetic algorithm for rule-set production GARPa group of researchers predicted that the southeastern United States is moderately to highly likely to be inhabited by zebra mussels and the Midwest unlikely to experience a zebra mussel invasion of water bodies.
Today, the invasion continues. For instance, inthe Massachusetts Department of Conservation and Recreation confirmed that zebra mussels had been found in Laurel Lake in the Berkshires. This was the first confirmed sighting in the Red River Basinwhich extends across the international border into the province of Manitoba.
New contamination was found outside treated areas of Lake Winnipeg in and they have also been found in the Red River near the lake in Selkirk Park in This resulted in reduced water supplies during a drought yearworsening water restrictions across the Dallas area.Zebra Mussels Die from a Natural Biotoxin: Dead Bacteria Kill Equally As Well Although phytoplankton is their preferred food, zebra mussels can filter out and consume bacteria as a food source (Mikheev and Sorokin ; Frischer et al.
). Invasive zebra mussels have devastating economic, recreational, and environmental impacts. The first Texas infestation was found in Lake Texoma in TPWD and partners closely monitor "positive" and "suspect" lakes, as well as other lakes we consider high risk for zebra mussel introductions (see.
In July , the North Dakota Game and Fish Department confirmed the presence of zebra mussel veliger in the Red River between Wahpeton, ND, and Breckenridge, MN. As recently as California similarly reported invasions.
In , an invasion of zebra mussels shut down a water pipeline in the Dallas area. R. De Nys, J. Guenther, in Advances in Marine Antifouling Coatings and Technologies, Summary of impacts.
Biofouling on sea cages causes mesh occlusion and a resultant decrease in productivity and fish health, as well as structural fatigue and cage deformation.
Consequently, biofouling is a significant management issue resulting in increased operational expenses.
Zebra Mussel Fact Sheet. The zebra mussel (Dreissena polymorpha) is a small bivalve originally native to the Caspian Sea region.
Zebra mussels reached North America in the mids in the ballast water of a ship. is and in to a was not you i of it the be he his but for are this that by on at they with which she or from had we will have an what been one if would who has her.