Zebra Mussel- direct all questions here!

[dmdoss]

Are they good or bad?

Good for vis, as they filter so much water. Bad as they stick to everything! These things are getting to be a problem in some lakes. What do ya'll think?

 

[archman]

Divers like them, in that they clean up the water. Divers hate 'em, in that they're pretty dang painful to bang into.

You'll find that many biologists are now split on the damn things. On the one hand, they're an invasive exotic that have modified the natural habitat, both in the water column and on the substrate. On the other hand, they're now believed to be serving as surrogate habitat to bottom-dwelling native species.

About the only demographic that isn't really split on zebra mussels are boaters and civil engineers. These are the people that have to clean them off their hulls, pipes, drains, etc...

It doesn't really matter what people think. The species isn't going away in the forseeable future. The only large-scale eradication project involved dumping vast quantities of potassium chloride into relatively small, confined bodies of water. And the procedure's too new to see how reliable it is.

 

[Dive-aholic]

An established zebra mussel colony was discovered in Lake Mead (AZ/NV) this past Saturday and confirmed yesterday. This is 1000 miles west of any other known zebra mussel colonies. See my website home page for more details and a couple of links.

 

[james croft]

Virginia thinks they have eradicated their only known population at Millbrook quarry in Manassas by using that method. Latest survey looks promising. This quarry was a popular dive site. I would not be surprised to learn that there may be another location for zebra mussels in Virginia. Some suspect other zebras may be introduced by unethical divers at certain dive sites such as private quarries to increase vizibility. I hope this has not happened as this invasive species is not wanted in Virgina. Hopefully anyone aware of zebras found in Virginia will notify the VA Dept. of Game so proper measures may be taken to control them.

 

[ams511]

How do they move from one body of water to another. I understand they were introduced into the Great Lakes by foreign ships dumping their ballast water into the lake. But how did they get to Lake Mead?

 

[archman]

Birds. Small boat hulls. Aliens. Take your pick.

 

[Dive-aholic]

NPS officers at Lake Mead have found boats with zebra mussels a few times in the past. There's a popular article about a house boat that was stopped from being launched in 2004 because a NPS officer saw zebra mussels on the hull. These things can survive a lot. They get in the engines and on the hulls and when the boaters move on to a different lake, they bring them with. Lots of boaters come to Lake Mead from all over the country.

 

[maj2]

Apparently the zebra muscle is being "muscled out" of some of the great lakes by the quagga mussel, another invasive exotic to the Great Lakes. This November 206 article from The Globe and Mail is an interesting bit of history on the mussel infestation.
http://www.theglobeandmail.com/servlet/story/LAC.20061125.ZEBRA25/TPStory/TPScience/Ontario/.
Although the zebra and quagga mussels have helped the visibility of the Great Lakes, they have totally messed up the bottom of the food chain. Interesting article here on how they are affecting whitefish and salmon populations via the food chain in Georgian Bay: http://www.georgianbay.ca/pdf/update/vol16no3.pdf
The round goby is another problem exotic. Although it will apparently eat the zebra mussels, it also eats huge quantities of various fish eggs and is affecting perch, bass populations (probably other fish as well). This 2005 Detroit News article describes a fishing tournament where 400 anglers caught 5000 invasive gobies and only a single native perch over five hours (Muskegon Lake).
http://detnews.com/2005/project/0508/14/Z06-275416.htm

I've also seen beaches of mussel shells a foot deep. No more barefoot beach walks.

 

[james croft]

It is suspected that some folks may have diliberately introduced zebras into murky quarries to improve visibility. But only The Shadow Knows.....

 

[DavidPT40]

I thought suspended silt and sediment were the main causes of murky water.

Also, check out this picture of a crayfish covered in Zebra mussels.