Freshwater Mussels Question

[JC]

I don't own a pond (yet!) but had a question that I hoped some of the group members could provide input on. I visit a variety of local ponds in my area and each seems to have its own unique dynamics, often based on the plant life and animals that reside there.

 

One local pond has EXTREMELY clear water and the fish are very wary. Otherwise, the population seems to be in very good health and the balance of bass, crappie and bluegill appears to be good.

 

I noticed 2 species of what appear to be clams. I did some research and all the sites listed these as "freshwater mussels". The numbers of the smaller species of mussel is unbelievable. If you look closely, you can see the breathing holes and there are thousands or millions of these little shellfish everywhere in the shallows. I am unsure how deep they might go and if they are present in the middle of the pond.

 

I am assuming these mussels are responsible for the clarity as they filter the water in order to feed.

 

Has anyone seen mussels in their ponds? If so, what effects do they seem to have on pond dynamics?

 

Thanks in advance.

[Josh Milczski (Omaha)]

Depending on the species of mussels will determine whether they are good or bad for the body of water, but I would imagine if there are "millions" like you say that it isn't a good thing long term.  Whatever you do, do not introduce them into another body of water.

[Bruce Condello]

Great question!  Keep in mind that certain types of freshwater clams, mussels etc can be HIGHLY DESTRUCTIVE if moved from one body of water to another.  Always be careful about moving boats, or even unwashed wading boots that could carry these little critters! :-)

 

That being said, the answer is YES, that the presence of filter feeders like mussels can result in dramatic increases in water clarity.  I always suggest that people look into redear sunfish (climate allowing) as a possible member of the fish community to feed on shelled invertebrates.  Redears can get very big, very quickly on this sort of diet.  Typically there is little to no competition for this resource.  There is no more exciting fish in freshwater than big, hawg redears!!

[JC]

I did not clarify originally but these look like "clams" to the novice observer. They are nothing like zebra or quagga mussels.

 

The smaller version is clam shaped and 1 - 1.5 inches across. These are so plentiful that if you scoop up a handful of sand, you might have 4-6 in the handful.

 

The larger ones are more oval  and are 3-4.5 inches long. They protrude slightly from the sand.

 

This pond has a swampy section that occasionally floods from a nearby creek. The smaller clams are abundant naturally in the creeks and rivers nearby.

 

Every resource mentions that freshwater mussels attach to the gills of freshwater fish and are moved around this way.

 

It is a common practice for people locally to move fish from pond to pond, trying to increase numbers of their favorite species.

 

In light of some of the recent invasive species problems I think an overall culture change may be in order in terms of fishing practices in North America and elsewhere.

 

Oddly enough, I happened to be at a seminar where a really geeky biologist was speaking on largemouth bass. It turns out the species was introduced to my area in the 1800's and went on to follow a classic invasive species pattern of eating everything in their path, reproducing in great numbers, and later a population crash. Eventually things leveled off, but several native species declined drastically after largemouth became established.

 

What does all this have to do with clams?? Nothing....unless the clams hitched a ride in the gills of a big fat bucketmouth that swam in during a flood.

[Josh Milczski (Omaha)]

The recent redear record fish was (theoretically) grown on mussels.

[Zach Pierce]

I still think some redears in the pond would be a good think, plus if you just had say 5-10 of them, they would grow to a nice size with all that food, not sure if you would ever catch one, but just knowing it could happen would be a great feeling.

 

I put 30 in my pond in 2009 and have yet to catch one.

[JC]

Attached is a pic of the 2 species of freshwater mussels. The smaller ones are typically around 1 inch across.