The Situation: Quagga and also zebra mussels room aquatic invasive varieties that are native to east Europe. The quagga mussel source from Dnieper river drainage of Ukraine. The zebra mussel was first described from the lakes of south east Russia and also its herbal distribution additionally includes the Black and also Caspian Seas. Quagga and zebra mussels gain their common names from the zebra-type striping on the shells. Both mussel types are little and generally grow to the dimension of a fingernail. They room prolific breeders and also these mussels can affix to both hard and also soft surfaces in freshwater ways.

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Zebra mussels have a long history of invasion and also have successfully developed in an excellent Britain (1824), The Netherlands (1827), The Czech Republic (1893), Sweden (1920), Italy (1973), the good Lakes in the USA (1988), and also California (2008). Quagga mussels were first found in the USA in the an excellent Lakes in 1989, Nevada in 2007, and also California in 2008. Ballast water discharge native transoceanic ships is assumed to it is in responsible for the long distance spread of zebra and quagga mussels from their original residence ranges in east Europe. Short distance spread between fresh waterways within nations most most likely occurs via the motion of entertain boats. This wake up when boats are no cleaned and dried adequately and contaminated watercraft room then moved from infested waterways to pristine water bodies where mussels space accidentally introduced. These mussels can survive for 3-5 days out of water without enduring lethal desiccation.

Where quagga and zebra mussels co-exist, quagga mussels appear to outcompete zebra mussels, and also quagga mussels have the right to colonize to depths greater than those accomplished by zebra mussels and also are an ext tolerant of cooler water temperatures. Because that example, in Lake Michigan, zebra mussels consisted of 98.3% that mussels in 2000, by 2005 quagga mussels stood for 97.7% of accumulated mussels. Zebra mussels were discovered at densities of approximately 899 every square meter, but quagga mussels now dominate at 7,790 mussels per square meter. Quagga mussels have been found at depth of up to 540 feet in Lake Michigan where they filter feed year round.Consequently, quagga mussels may become the an ext problematic of these two mussel species in California.The Problem: Quagga and also zebra mussel intrusions have had catastrophic impacts in the ecosystems in which they have established. This organisms clog water intake frameworks (e.g., pipes and also screens), which considerably increases maintenance expenses for water treatment and power plants. Recreational tasks on lakes and rivers space adversely impacted as mussels accumulate top top docks, buoys, watercraft hulls, anchors, and beaches can become heavily encrusted.

The shells of both mussel types are sharp and can cut people, which pressures the put on of shoes when walking along infested beaches or end rocks. Mussels adhering to boat hulls can increase drag, influence boat steering, and clog engines, all of which have the right to lead come overheating and engine malfunctions. Ecological difficulties also an outcome from mussel invasions. Zebra and also quagga mussels have the right to kill indigenous freshwater mussels in two ways: (1) attachments to the shells that native varieties can kill them, and also (2) these invasive species can outcompete indigenous mussels and other filter feeding invertebrates because that food. This trouble has been particularly acute in some locations of the USA that have actually a really rich diversity of indigenous freshwater mussel species.

The encrusting that lake and river bottoms deserve to displace indigenous aquatic arthropods that require soft sediments for burrowing. In the great Lakes this had lead come the please of amphipod populations that fish depend on because that food and the health of fish populations has been severely affected.

These mussels have been associated with avian botulism outbreaks in the good Lakes which have actually caused the mortality of 10s of thousands of birds. Since of their filter feeding habit, it has been estimated that this mussels have the right to bioaccumlate essential pollutants in your tissues by as much as 300,000 times when contrasted to concentration in the water in which they room living. Consequently, this pollutants have the right to biomagnify as they room passed up the food chain once contaminated mussels are consumed by predators (e.g., fish and also crayfish), who consequently are eaten by other organisms (e.g., recreational fishermen who eat contaminated fish.) High mussel populations deserve to increase water acidity and decrease concentration of dissolved oxygen.

Interestingly, invasions by quagga and also zebra mussels have been documented as having actually some positive affects on receiving ecosystems. For example, filtration that water by mussels together they extract food removes particulate matter. This filtration has actually improved water clarity, and reduced the eutrophication of polluted lakes. In part instances these renovations may have benefited neighborhood fishing industries. Conversely, improved water clarity allows penetration of light to higher depths i m sorry can alter the species composition that aquatic plant communities and associated ecosystems. This boosted water quality is thought to help algal blooms that obtain washed ashore where they rot make recreational beaches unusable. Further, the highly effective removal that phytoplankton deserve to deprive other aquatic varieties of food.


 Invasion success in some locations of California might be influenced by water chemistry. Waterways about the Sierra Nevada mountains may have actually insufficient calcium (an aspect needed for shell growth) and some lakes in northeast California may be also salty for mussel survival. However, the general consensus is that many freshwater methods in California will be accommodating come zebra and also quagga mussels.

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Economic affect and Management: Zebra and quagga mussel invasions develop an enormous financial burden because of the have to continuously and actively manage this pests. It has been approximated that it expenses over $500 million (US) every year to control mussels at power plants, water systems, and also industrial complexes, and on boats and also docks in the an excellent Lakes. Similar yearly management prices are anticipated because that California. Because that example, a current estimate (2009) by the military Corps of engineers indicates the quagga mussels could cause yearly loses of $22 million to the Lake Tahoe region should they establish there. The report details potential damage to tourism, decreased property values, and also increased maintain costs. Management of problem mussel populations may be completed in various ways in California. Water draw downs in canals and aqueducts could be supplied to death mussels by dry them out. Poisons such as chlorine and also copper sulfate which room toxic come quagga and zebra mussels might be work under certain conditions.