RESULTS AND DISCUSSION
Our results were statistically significant
(Bulger, 1992) and somewhat surprising (Schmeerl,
1967). Through our intimate contact with 10,113
individual mussels of twenty-eight species in
thirty-two ZIP codes, we formulated a multi-part
hypothesis regarding the habitat and lifestyle
choices of these enigmatic beasts. At first it may
appear that our hypothesis is based on wild
conjecture, but we promise that all of the really
important bits are firmly grounded in accurate
field observations and totally objective facts
(Custer, 1867).
Most of the mussels we studied exhibited a
strong preference for stable and relatively
unpolluted aquatic habitat, with a notable
exception being
Utterbackia imbecillis which was
found to survive and even thrive in such
inhospitable habitats as exposed sand bars, drying
puddles, and treetops. Fortunately for us, given our
obsessive Calvinistic need to divide the natural
world into tidy and predictable categories, the
other species we studied were more tractable and
quickly learned to play by the rules (Gazpacho,
1999). Our research shows distinct trends of
behavior among these “good” mussels as follows.
Trend 1: Mussels prefer to live in habitat that is
free of leeches, snapping turtles and excessively
active fish; mussels are never found in areas
frequented by poisonous snakes (Fig. 1). This last
“cottonmouth effect” is evidenced by the sharp
drop we noted in the numbers of mussels collected
in the vicinity of Agkistrodon piscivorus.
Trend 2: Mussels are highly influenced in their
habitat choices by seasonal temperature changes,
preferring air and water temperatures roughly
equivalent to those preferred by the average
human (Brody, 1974). Our data show that mussels
actively seek comfortable temperatures by moving
to the sunnier side of the river in cold weather and
moving to the shadier side in hot weather (Fig. 2).
When the weather is intermediate such trends
become less clear, with some mussels (usually
younger males) moving to shady areas, and others
(usually older females) opting for sunny areas.
Trend 3: Mussels exhibit avoidance behaviors
during inclement weather. When a light rain
shower begins, mussels undertake a rapid migration
toward the deepest portion of the sampling area,
quickly moving out of reach of all but the most
long-armed researchers (Cabbage, 1982). By the
time a light rain shower turns into a thunderstorm,
the local mussel populations have effectively
disappeared (Fig. 3). At such times, we have found
it best to seek hot showers and microbrews until
the mussels choose to return to the surface. In a
similar behavior not yet observed by us personally,
it has been reliably reported that mussels in colder
climates often migrate southward in wintertime by
clinging to the backs of geese (Old man who lives
under bridge, pers. comm., 2001).
Trend 4: Mussels prefer to live in pristine,
unpolluted water (Fig. 4) within five miles of a
park, library, grocery store, and movie theater
(Uvula, 1999). Mussels are seldom found
immediately downstream of industrial or municipal
wastewater outfall pipes. Our data also indicate
that mussels have the ability to distinguish
between types of wastewater discharges, possibly
on the basis of smell, taste, texture, or official
signage. For example, we found that large numbers
of mussels will inhabit the area immediately
downstream from the cooling water outfall for a
chocolate factory, but mussels are seldom found in
conjunction with the “chunky style” wastewater
discharge of a large metropolis (Juniper, 1996).
Mussels are never found immediately downstream
from hog and chicken farms, metal-plating
facilities or nuclear reactors (Jerkins, 2000).
After taking a few minutes to analyze the
clear trends outlined above (Klezmer, 1954), we
reached the conclusion that freshwater mussels are
capable of making complex choices regarding
habitat and lifestyle (Cornball, 1997). Until now
many scientists and normal people have assumed
that mussels are without intelligence, free will, or
emotional baggage, but we trust that our findings
will open such closed minds to a pearly dawn of
new understanding and empathy for this most
maligned and neglected of creatures, this tiny glob
of dirty mucus in a calcium-based casket, this shy
voluptuous beauty with whom we have shared so
many hours of silent, yet deeply passionate, joy.
ACKNOWLEDGMENTS
We wish to thank the many bivalves who helped
to make our research possible, except for
U.
imbecillis which was not as helpful as it could have
been. We thank the legions of former and current
employees of the U.S. Army Corps of Engineers,
the U.S. Soil Conservation Service, and the West
Tennessee Basin Authority for ensuring that most
of the rivers and creeks in our region have been
permanently stripped of their natural meanders,
woody debris, riparian vegetation and freshwater
mussels, thus greatly reducing our sampling
obligations. We thank the five anonymous
reviewers who told us that our manuscript was a
delusional piece of crap, because we know they
were just kidding (Vito, 2002). Ha ha! Finally, and
most importantly, thanks to Doctor Dolittle for
solving the Shellfish Riddle and teaching us the
importance of being a Good Noticer.
Lifestyle Choices of the Freshwater Mussel (unionidae) in West Tennessee
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