Muskrats are usually the culprit. They bring mussels to their home feeding
areas or just to the nearest secluded  bank, and leave them to expire or at
least weaken. They then slurp out the animal, leaving behind often
pristine, cleaned shells - but usually with some claw-scratches on the
outside. They often bring up many mussels, some of which they forget about
- you can find live ones in the piles of dead ones sometimes. Muskrats are
not the brightest bulbs on the Christmas tree. Raccoons are a different
matter - they have little patience and usually crack open the shells to get
at the animal.

I'm sure they may lose some to other scavengers, but muskrats can be pretty
pugnacious. I always think twice before sticking my hand into a muskrat den.





At 05:59 PM 4/7/2002 -0700, you wrote:
>For those who may be familiar with searching for freshwater bivalves--
>and those who might take a guess anyway,
>
>Here's a question that Art Bogan, who co-authored The Freshwater Mussels of
>Tennessee, couldn't definitively answer:
>
>How come there are so many INTACT pairs of fragile mussels lying on the
>banks of rivers? I found numerous pairs on the banks of the Withlacoochee
>River in Florida and some of them still had bits of fresh adductor muscle
>inside.
>
>Art told me that most of these are probably fished out of the banks by
>muskrats or raccoons. He guessed that perhaps the predators leave the
>mussels out on the banks until they open.
>
>But if they lay out for so long, either the predators have to wait an
>awfully long time or competitors would reap the benefits.
>
>There's no way the mussels could be pried open without damaging the
>shell--unless they have some means of anesthetizing the mussel into relaxing
>quickly?
>
>Any ideas? Is this a job for Marty Stauffer lying in wait with his camera to
>find out the truth?
>
>David Kirsh
>Durham, NC

G. Thomas Watters, PhD
Curator of Molluscs
Museum of Biological Diversity
The Ohio State University
1315 Kinnear Road
Columbus, OH 43212  USA
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Visit the Mollusc Division at:
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