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Now and again it strikes me that the things I enjoy doing
are not the things most other people enjoy doing.
Take grubbing for mussels.
This activity involves sinking your hands into a streambed
and working your fingers through the sand and gravel to feel for the shells of
mussels--smooth, hard, vertically-oriented disks, which might be as small and
compressed as the face of a man’s wristwatch, or larger and thicker than an
adult’s hand.
It’s difficult for me to say why I enjoy this activity. There’s
something primal in the mental state it induces, akin to states induced by hunting
and fishing and foraging, but beyond that, I’m not quite sure how to
characterize it. I can say
that I’m not alone in losing myself as I grub. One of the rules when you’re with a group is not to grab the hands or feet of fellow grubbers underwater, especially when they’ve got that faraway, raccoon look on their face.
that I’m not alone in losing myself as I grub. One of the rules when you’re with a group is not to grab the hands or feet of fellow grubbers underwater, especially when they’ve got that faraway, raccoon look on their face.
So there are select other people who enjoy grubbing for
mussels, or who are at least find it tolerable in the name of citizen science.
That explains how more than twenty of us wound up on our hands and knees in the
shallow water of the Sangamon River on the Saturday morning of Labor Day
weekend, in an effort organized by the Upper Sangamon River Conservancy (USRC).
We were there, just downstream of the covered bridge at the Lake of the Woods
Forest Preserve, to collect as many live mussels as we could in a little over
an hour of searching, repeating a survey I participated in back in 2012.
Our findings this time around were quite similar. We
collected 310 individual mussels including representatives of 15 different
species, versus 314 and 13 in 2012. Neither of the two new species, a
threehorned wartyback and a fawnsfoot, came as a big surprise, given the
location and habitat, but it’s still cool that they were found.
Our most massive specimens were plain pocketbooks, some of
which probably would have tipped the scales at more than two pounds (although
weighing them wasn’t on the agenda). Our biggest specimens for shell
circumference were pink heelsplitters, which grow to the size of a small dinner
plates. The common names for many freshwater mussels are equally colorful and
descriptive; among those we found were also pistolgrips and pimplebacks,
threeridges, deertoes, Wabash pigtoes and fatmuckets.
The mussels we collected looked to be in good
condition, they represented a wide range of ages and some of them were gravid. According
to Sarah Douglass, a field biologist with the Illinois Natural History Survey at
UI who oversaw the scientific aspect of our survey, “it means they’re living
well into maturity and reproducing.”
Douglass pointed out that our findings also
provided other important indications about the health of the river. The
continued presence of mussels there suggests the habitat has not been
significantly degraded in recent years, and mussel reproduction in the stream
also signifies that certain fish species are thriving there, since the larvae
of freshwater mussels live on specific fish early in their development.
Would you like to experience the Sangamon for
yourself and learn more about the life it supports? Check out the Upper
Sangamon River Conservancy. It’s a group established in 2009 that seeks to “preserve,
maintain, monitor, and promote public use and awareness of the Sangamon River.”
Information available at http://sangamonriver.org/. New members are always welcome.
