Zebra Mussel  (Dreissena polymorpha)

DESCRIPTION

The Zebra Mussels, Dreissena polymorpha, are small, fingernail-sized, freshwater mollusks, native to the Caspian and Black sea region Eurasia. They are up to 1 inch in length and has a striped pattern on their shell (thus the name "zebra" mussel). It is believed that they are accidentally introduced to North America via ballast water from a transoceanic vessel. Zebra mussels were first discovered in Lake St. Clair in the mid 1980s. They have spread very rapidly to all of the Great Lakes, inland waterways, and several states rivers (including the St. Lawrence Seaway and the Hudson, Illinois, Mississippi, Ohio, Arkansas, and Tennessee rivers). Zebra mussels colonize on docks, native mollusks, nets, water pipes and valves, etc. In 1991, another zebra mussels species, Quagga mussels (Dreissena bugensis), was identified in North America. These species also have found in the St. Lawrence Seaway, Lake Ontario, Lake Erie, and Saginaw Bay in Lake Huron. The following information about zebra mussels will provide clear answers for educators and students.

IMPACTS

Zebra Mussels can have great impacts on our economy, and lakes & oceans' ecosystem. Most significantly, the mussels are extremely efficient filter-feeders, consuming large portions of the microscopic plants and animals which form the base of the food chain. Over time, this feeding behavior can affect a lake's entire ecological balance, causing significant shifts in native species populations.

In addition, one of negative effects are caused by their rapid reproduction. Zebra Mussels have clogged up water and drain pipes at municipal water supplies and at industries. They are expected to cost the US $5 billion in control efforts and reparation. Zebra Mussels have displaced native freshwater mussels of the area, and drastically altered the food web. The zebra mussel population continues to grow and no immediate end is foreseen. 
(modified from  http://massbay.mit.edu/exoticspecies/invaders/factsheet.html). 

Eurasian zebra mussels, Dreissena polymorpha, (Pallas), were introduced via ballast to the Great Lakes in the mid 80s. They have spread very rapidly to all of the Great Lakes, inland waterways, and several states rivers (including the St. Lawrence Seaway and the Hudson, Illinois, Mississippi, Ohio, Arkansas, and Tennessee rivers). 

Source of exotic species introduction: Ballast Water 
(revised from: http://massbay.mit.edu/exoticspecies/ballast/)

What is Ballast Water? Ballast water helps maintain ship's stability during transit along coasts and on the open ocean. Therefore, most ships fill their ballast tanks with water. For example, large ships often carry millions of gallons of ballast water. This water is taken from original coastal port areas and transported with the ship to the next port of call where the water may be discharged or exchanged.

What are the Problems with Ballast Water? Coastal port areas are home to a wide variety of organisms that live in the water and bottom sediments. As a ship loads ballast it also loads many of the organisms living in that port. These organisms range in size and phyla, from microscopic plants and animals to mussels, crabs, and even schools of fish! The ballast water of shipping vessels has been a primary method of exotic species introduction throughout the world. Scientists estimate that as many as 3,000 exotic species per day are transported in ships around the world, however, not all transported species survive the trip and their new home. Some of the species that do survive the trip are able to thrive in their new environment. Therefore, zebra mussels cause disruptions in the natural ecosystem, economic troubles, and even carry human diseases.

1993   Link

1995   Link

1997   Link

1999   Link

The European community, after two centuries of infestation, and the Great Lakes community, after years of infestation, haven't been able to develop a chemical toxicant for lake-wide control that isn't deadly to other aquatic life forms.

In some parts of Europe, large populations of diving ducks have actually changed their migration patterns in order to forage on beds of zebra mussels. The most extreme case occurred on Germany's Rhine River. Overwintering diving ducks and coots consumed up to 97 percent of the standing crop of mussels each year. High mussel reproduction rates, however, replenished the population each summer.

In North America, the species most likely to prey on relatively deep beds of zebra mussels are scaup, canvasbacks, and old squaws. But populations of these species are quite low; in fact, canvasbacks are so rare that they are protected. In the Great Lakes, diving ducks are migrating visitors, pausing only to feed during north-land southward migrations. However, Canadian researchers have documented increasing numbers of migrating ducks around Pt. Pelee in western Lake Erie, and these ducks were observed to be feeding heartily on zebra mussels. In southern Lake Michigan, zebra mussels encrusting an underwater power plant intake attracted flocks of lesser scaup. Unfortunately, some were pulled into the intake pipe and drowned. The stomachs of these dead scaup were full of zebra mussels. Mallard ducks also are frequently observed foraging on zebra mussels on shoreline rocks and shallow structures. In addition, freshwater drum, or sheepshead, are known to feed substantially on zebra mussels; and yellow perch have been observed feeding on juveniles, particularly when they are detached and drifting.

One novel approach to controlling zebra mussel populations is by disrupting the reproductive process. Zebra mussel eggs are fertilized externally; therefore, males and females must release their gametes (sperm and eggs) simultaneously. After release, zebra mussel sperm remain viable for only a short time-perhaps only a few minutes. Disrupting the synchronization of spawning by males and females may effectively reduce the numbers of fertilized eggs. Researchers are currently studying the environmental cues and physiological pathways that coordinate zebra mussel spawning activity 

(Soruce from Zebra Mussels in North America: Fact Sheet 045, Ohio Sea Grant, http://www.sg.ohio-state.edu/PDFS/PUBLICATIONS/FS/FS-045.pdf)

Aquatic Nuisance Species: Mississippi State University Extension Service
    http://www.msstate.edu/dept/crec/ans.html
This site introduces nonindigenous aquatic species, their impacts of escaped aquaculture species, specially, impact of zebra mussels and life history and biology of zebra mussels.
  Zebra Mussel and Aquaculture  http://www.msstate.edu/dept/crec/zebraqua.html

Aquatic Nuisance Species: Algae, Bythotrephes, Gobies: Ohio Sea Grant
    http://www.sg.ohio-state.edu/SEARCH/TOPICS/T-ANS.HTM
Publications from Ohio Sea Grant explore various exotic species. 
FS-045  Zebra mussels in North America: The invasion and its implications.
FS-054  Slow the spread of zebra mussels and protect your boat, too.
FS-058  Zebra mussel migration in inland lakes and reservoirs: A guide for lake managers.
FS-059  Safe use of zebra mussels in classrooms and laboratories.
FS-060  Showing Sea Grant's muscle with the zebra mussel.
TB-026  Showing Our Mussel.
TB-030  Zebra Mussel Update: A 1995 Report of Research.

Exotic Species Online Publications Catalog: Michigan Sea Grant   
    http://www.engin.umich.edu/seagrant/pubs/onlline.htmls 
Exotic Species Factsheets related to Zebra Mussels: 
Potential Control of Zebra Mussels Through Reproductive Intervention             
      http://www.engin.umich.edu/seagrant/pubs/on/msg94-703.html
Slow the Spread of Zebra Mussels and Protect Your Boat Too
      http://www.engin.umich.edu/seagrant/pubs/on/msg94-713.html
Zebra Mussel Distribution Map (of Michigan only)   http://www.msue.msu.edu/seagrant/zmfiles/zmap&list.html
Zebra Mussels in the Great Lakes   http://www.engin.umich.edu/seagrant/pubs/on/msg92-700.html
Zebra Mussels in North America: The Invasion and its Implications 
      http://www.engin.umich.edu/seagrant/pubs/on/msg97-503.html
Zebra Mussels May Clog Irrigation Systems   http://www.engin.umich.edu/seagrant/pubs/on/msg93-701.html
Zebra Mussel Migration to Inland Lakes and Reservoirs   
      http://www.engin.umich.edu/seagrant/pubs/on/msg93-500.html
Safe Use of Zebra Mussels in Classroom and Laboratories 
      http://www.engin.umich.edu/seagrant/pubs/on/msg93-703.html

Florida Sea Grant's network of marine extension      
    http://gnv.ifas.ufl.edu/~seaweb/homepage/EXTENSION.HTML
This site provides a direct link between researchers and the people who need research results to improve the quality of life in the state's coastal areas. 
Zebra Mussel Awareness and Prevention  http://gnv.ifas.ufl.edu/~seaweb/homepage/SGEF73.HTM

Introduced fish: American Fisheries Society   http://www.afsifs.vt.edu/
Zebra Mussel   http://www.afsifs.vt.edu/zebra.html

National Zebra Mussel & Aquatic Nuisance Species Clearinghouse
    http://cce.cornell.edu/seagrant/nansc/anslibsindex.htm
This site is North America's most extensive technical library of publications related to the spread, biology, impacts and control of zebra mussels and other important aquatic nuisance, non-indigenous and invasive species. This site includes many useful reference bibliographies for many exotic molluscs and other aquatic exotic species.

Invasion of An Exotic Species: Stop the Zebra Mussel! (Virginia Sea Grant)
    http://www.vims.edu/adv/ed/zm/index.html 

This site introduces a Data Analysis Activity for Assessing Zebra Mussel Invasion Risk in Virginia for grades 8-12.

The Zebra Mussel Page (Wayne State University)
    http://www.science.wayne.edu/~jram/zmussel.htm
This site includes summary of Ram Lab zebra mussel research, zebra mussel slide show, a zebra mussel glossary, answers to frequently asked questions, and publications.

Sea Grant Nonindigenous Species: sgnis   http://www.sgnis.ord/
This site contains a comprehensive collection of research publications and education materials produced by Sea Grant programs and other research institutions across the country on zebra mussels and other aquatic nuisance species.

Zebra Mussel (Ontario Federation of Anglers and Hunters) 
    http://www.ofah.org/invading/invading.htm
This site provides brief description of zebra mussel and Ontario distribution map.

Zebra Mussels and Other Nonindigenous Species (Sea Grant Great Lakes Network)
    http://www.seagrant.wisc.edu/greatlakes/GLnetwork/exotics.html
This site includes information on threats, controls, prevention, and impacts of zebra mussel.

Zebra Mussel Update (ZMU) Newsletter
    http://www.seagrant.wisc.edu/publications/ZMU/index.html
This newsletter, The ZMU, was a 4- to 8-page quarterly national Sea Grant newsletter published from 1990 to 1997 by the University of Wisconsin Sea Grant Institute in cooperation with Ohio Sea Grant and Brunswick Marine. The ZMU reported on the spread of the zebra mussel throughout North America, the latest research results and control efforts. 

Zebra Mussels in Vermont 
    http://www.anr.state.vt.us/dec/waterq/ans/zebra.htm
This site includes description, impacts, Zebra Mussel Citizen Action Program, and distribution map in Vermont.

Aquatic Nuisance Species Program: The Zebra Mussel Threat (South Carolina) 
    http://water.dnr.state.sc.us/water/envaff/aquatic/zebra.html
This site introduces Aquatic Nuisance Species Program (zebra mussel)

Zebra Mussels in Virginia (Virginia Cooperative Extension)                    
    http://www.ext.vt.edu/pubs/fisheries/420-900/420-900.html
This sites includes the following title information on zebra mussels in Virginia: the Newest Invader of the Nation's Waters, Should Virginians Be Concerned? Economic Consequences, Understanding Its Lifestyle, Will Virginia Inherit the Great Lakes' Problem?  Can They Be Controlled? Key to Prevention Who's Working on the Zebra Mussel Proble.

Life History and Ecological Requirements of the Zebra Mussel (National Sea Grant)
    http://www.nsgo.seagrant.org/research/nonindigenous/zmlifehistory.html
This site includes useful information on life history of zebra mussels (adult and veligers), habitat needs, and special handling problems.

Zebra Mussels - A threat to Maryland waters (Maryland Sea Grant)
    http://www.mdsg.umd.edu/Extension/zebramussel.html
This site contains brief description of zebra mussel, potential damage, and control methods.

WDFW Zebra Mussel and Green Crab Task Force (Washington Department of Fish and Wildlife Task Force)
     http://www.wa.gov./wdfw/fish/nuisance/zmegctf.htm
This report provides educational resources related to zebra mussel and green grab.

Volunteer Opportunities - Washington Department of Fish and Wildlife   
    http://www.wa.gov/wdfw/volunter/zebramitten.htm
The Washington Department of Fish and Wildlife (WDFW) is seeking volunteers to assist in sampling and monitoring programs for zebra mussels and/or the Chinese mitten crab.