Pond Boss Forums INTRO Questions & Observations monster bluegill

Thanks CJ. I remember that thread now just hadn't read the whole thing.
While searching the subject I found this intresting: http://pubs.aina.ucalgary.ca/arctic/Arctic60-2-124.pdf
Study shows many mollusks/clams/snails can pass thru fish unharmed.
I wonder if they were alive in the fish's gut when a migrating bird ate them if they would survive the bird's gut. Talk about transporting non-native species!

ewest:

Could you add that chart to the archives, Sunfish ID thread?

I didn't know I had clams in my pond but I do. Discovered them last year. My pond is a dugout bog that I would have assumed had no clams. The bog had no standing water before I dug the pond. Last year when I opened up several HBG I found small clam shells in the stomach. Some fish were stuffed with them. The clams were perhaps only 1/8 inch accross. They looked to be all dead, just shell halves is all I found. They were generally brown with yellowish highlights. I've never seen a larger clam from my pond so I'm not sure if these are some type that don't get real big or of they are babies. Any guesses on what these might be here in MN?

Bz - In WI the small clams (freshwater mussels) were probably fingernail clams. There are four groups (genera) two most common -Pisidium (most species) and Sphaerium. Pisidium tends to be a little smaller than Spherium. Large ones are 1/4"-3/8".

Hey CJ, what's the status report to date on the pond you stocked with Asiatic clams? I'm thinking about trying them in a half-acre pond that will be a shellcracker pond. My second question would be, how would one go about collecting them? I just learned that they're native (according to the local paper) to the river that runs through my hometown.

Interesting side note: said river is one of three ecosystems being featured in an upcoming National Geographic as one of the most biologically diverse on the planet; one of the other two is a mesa somewhere in Africa, and the other is a rainforest somewhere in South America. A lot of anglers I know like to fish the river; I never have fished it much, wonder now if I should give it more attention. I do know it has some really beautiful longear sunfish, and the streams that feed it have a lot of rock bass; the river itself has everything from walleye to crappie to a thriving smallmouth population to gar to flatheads, etc.

Walt, since I only put the clams into the pond at the end of this past summer, I really don't know what the outcome will be... It will be a year or two until I really know much and probably 4 or 5 until I see any results if the clams even take hold in the pond.

Here is my personal take on Asiatic clams...

Obviously the name gives them away, they are NOT NATIVE anywhere in North America. They are native to most parts of Asia, Asia Minor and parts of Africa.

Precautions:

Stocking them into ponds first off may be illegal in your state so please check regulations before transferring or purchasing these clams to stock into your pond.

If you find that it is legal, then check these links: http://www.in.gov/dnr/files/Asiatic_Clam.pdf and http://nas.er.usgs.gov/queries/FactSheet.asp?speciesID=92 Check the information there to see if they are already in the watershed where your pond is. If they are already present, you know you are not adding to their spread. Although no studies have shown they out compete native bivalves, there is great concern that they may. However, they are most commonly found in sub par areas where native bivalves cannot survive do to pollution and other water quality issues.

Once you find out they are legal to stock and already present in your watershed, you need to also consider another issue. Asiatic clams can have issues like zebra mussels in clogging pipes and water intake systems. If your pond has piping, particularly intricate piping, the Asiatic clam probably is not a good option. Asiatic clams do no cling to objects like zebra mussels so they are no quite as big a problem as zebra mussels are. However, their larvae are free floating and can be drawn into a pipe. If that pipe has a bend, they may settle in a slack area, grow, die and over a couple years their shells may build up and can cause blockage in that pipe.

However, if your pond doesn't have any piping or the piping is simple this should not be an issue and they may be suitable.

Last, Asiatic clams are filter feeders and will filter your water. Under predation from RES, CC and other predators their numbers shouldn't get out of control. This is particularly true of more northern waters where they are prone to die offs. Be mindful of this and understand that if their numbers do grow uncontrolled they can alter water characteristics.

I don't know if Asiatic clams really assist in the growth of RES or other fish adapted to feeding on mollusks, but anecdotal evidence states they probably do... Keep in mind the legal and moral cautions, their water filtering habits as well as possible damage to your ponds piping system. If all these are not an issue they may be a great addition to the forage base in your pond for growing trophy RES.

Keep in mind their are also native fingernail clams which most likely will be utilized in much the same manor by RES and others. Most fingernail species only reach an 1/2" in size and this would indicate they are more easily preyed on during their complete life while Asiatic clams will outgrow the mouths of their predators after only a year or so.

I utilize two collection methods:

Running my fingers through sandy substrate, I'm able to feel for the clams and pull them out. They generally do not bury very deep and are easy to feel. Or you can visually walk along shallow areas and look for the clams. You can sometimes see their tracks in the bottom substrate and that will lead you to where they are. This is especially effective at night with a flashlight. I often collect them for us as bait in this manner as well. They make excellent bait for both sunfish and catfish! Crack the shell open, put the meat on the hook and hold on...

Interesting stuff to be sure. I read the thread you posted months ago, I guess when you stocked them, then re-read it yesterday which got me to thinking again about trying them...There's no piping in the pond I would stock them in; it is on a property with several other ponds, but there's no above-ground (i.e. none whatever that I know of) flow from one pond to the next as they're all old phosphate pits and thus each one is in somewhat of a hole.

I'll do some research on the area watershed, along with local laws. I do know the river I mentioned also has multiple species of endangered mussel, so evidently the Asiatics haven't done them in; a large (60 acres) lake I work with has some sort of freshwater clam, as the owner mentioned it and I've seen a good number of their empty shells along one shoreline. If I decide to stock the Asiatics I'll keep you and the forum notified of the progress of the experiment.