Zebra Mussels

Outdoor Professsor's Tips

Hello, I'm the OUTDOOR PROFESSOR from DiscoveringTheOutdoors.com/

Here's your outdoor tip on zebra mussels.

Non-native zebra mussels were found for the first time about 20 years ago in North America. It is thought they were carried in the ballast tanks of ships from western European ports to Lake St. Clair and the lakes Huron and Erie. Now, a great deal of attention has been on the ballast water of cargo ships to prevent more introductions of this invasive animal into the Great Lakes region.

The name “zebra mussel” comes from the striped pattern of their shells. The pattern does vary from very dark to the point of only light stripes on some shells. The mussels can grow to a size of about 50mm but are only 5-10 mm during their first year of age.

Zebra mussels have upset the aquatic food chains of many inland lakes in the United States Their voracious filter systems deplete the microscopic organisms that are critical parts in each lake’s ecological food system. This affects the food for larval and juvenile fish that support the sport and commercial fishing industries.

As other mussels, zebra mussels attach themselves to hard surfaces in the water. Unlike others, though, zebras will attach to native mussels—a behavior known as bio-fouling that reduces the populations of native mussels. Of great concern is this may eliminate some of the rarer species of mussels. The affinity of zebra mussels to attach to hard surfaces also has made water intake structures for power and municipal water treatment plants susceptible to colonization and causes significant reductions in pumping capabilities and can cause periodic plant shutdowns.

Research shows that zebra mussels rapidly accumulate organic pollutants such as PCBs and PAHs with levels 300,000 times greater than concentrations in the natural environment. These items are deposited in their pseudofeces and can be passed up the food chain to fish and waterfowl. Humans are in turn exposed to these pollutants by eating the fish and birds.

Invasion biology has been expanded by the intrusion of zebra mussels. US Legislation has been introduced to treat the ballast water of ships. Salt water acts as a natural preventative against the zebras so it is now required that all ocean vessels flush ballast tanks with seawater before they enter the Great Lakes area.

By the early 1990s, the mussels traveled to many major river systems connected to the Great Lakes watershed moving down the Ohio, the Mississippi, and the Missouri Rivers. The quagga mussel, another invasive mussel species similar to the zebra mussel, was found in Lake Erie in 1989. It now has spread to all the Great Lakes areas replacing the zebra mussel as the predominant invasive mussel species. Quagga and zebra mussels have been found west of the Continental Divide.

Millions of these mollusks are now living in the Great Lakes system. They have no natural predators in North America. Attaching to each other when they settle, large clusters occur in small areas with as many as 700,000 zebra mussels have being found in only one square yard on boats, pilings, and pipes.

Although zebra mussels are efficient at filtering large volumes of water greatly improving water clarity, they contribute to the explosive growth of harmful algal blooms in Saginaw Bay and other fresh bodies of water. The mussel is low in fat and its shell has no nutritional value forcing fish to expend a great deal of energy capturing and digesting the mussel. Also, there are fewer food options as these mussels displace better food sources.

Quagga and zebra mussels are now investing most fresh water bodies throughout the United States.

Zebra mussels are moved throughout rivers and lakes by hitching-hiking on boats, trailers, barges, sea planes and other aquatic equipment. In their microscopic juvenile stage, they can be carried in boat bilge water, live wells, bait buckets and diving gear. Precautionary steps after boating and fishing will help prevent the spread of these invasive mussels. It’s important to:

• Check boat and trailers for mussels before leaving a body of water
• Discard aquatic vegetation in the trash after boating
• Drain all the water from the boat including the bilge, live-well and engine system.
• Dry the boat and trailer in the sun for at least five days or clean the boat and trailer in a car wash
• Leave all aquatic bait behind
• Everyone drawing water directly from a mussel infected body of water must protect their water systems from infestation
• Inform others of the dangers of zebra mussel infestations

There are no known environmentally friendly methods for eliminating zebra mussels. Public assistance to prevent the spread of these invasive species and reporting infestations is the only solution to reduce the negative effects of zebra mussels on the environment.

Keep track of daily outdoor news by visiting our blog at DiscoveringTheOutdoors.com/blog / and please like our Facebook Page at Discovering the Outdoors.

Additional outdoor tips can be received by subscribing to the Outdoor Professor Tips on iTunes or Stitcher. If you enjoy outdoor tips, you’ll also find an e-book at Amazon.com with a collection of the Outdoor Professor Tips.

References-Additional Reading

Harmful Aquatic Hitchhikers: Mollusks: Zebra Mussel
http://www.protectyourwaters.net/hitchhikers/mollusks_zebra_mussel.php

Zebra Mussel Frequently Asked Questions
by Jeffrey L. Ram, Ph.D., Wayne State University, Detroit, MI 48201
http://sun.science.wayne.edu/~jram/zminter2.htm

The Zebra Mussel Invasion
http://www.noaa.gov/features/earthobs_0508/zebra.html

Nature Quotient.
eBook @Amazon.com

Outdoor Professor’s Tips: Exploring the Wonders of Nature
eBook @Amazon.com