Proposed Research
The physiological implications of selecting for
the trait of angling vulnerability in largemouth
bass.
My research involves utilizing largemouth bass
that have been selected to be either highly or
minimally vulnerable to angling pressure. The
general premise is that repeated selection of
a specific trait in fish can lead to phenotypic
and genetic changes within a population, which
may have evolutionary consequences over time.
The field aspect of my research will be carried
out at two experimental pond facilities that are
part of the Illinois Natural History Survey, located
in Champaign, IL and the Sam Parr Biological Station
(three hours south of Champaign). I will be utilizing
two populations of largemouth bass that have been
bred for the heritable trait of angling vulnerability
since 1977. Each group of bass has been bred selectively
based on the “catchability” of the
previous generations. There are now two groups:
one that is not very vulnerable and a second group
that is highly vulnerable to angling. Using these
particular bass, I am proposing to conduct a series
of experiments related to general activity patterns
and exercise performance, to determine if there
are any differences between the two groups.
I am interested in looking into the links
between general activity patterns, energetics
and growth throughout the summer of 2007. I
would like to implant small electromyogram (EMG)
tags into several bass (high and low vulnerability)
that are currently 6-8” in size (believed
to be cannibals) to monitor patterns of activity
when they are feeding and moving around in a “normal”
situation (not during a reproductive period).
As well, I would like to measure some physiological
characteristics of the two groups of bass (those
not equipped with EMG tags). There are several
hundred fish that are much smaller and would be
suitable for conducting physiological assays to
examine fat, water, and protein contents, and
hormone concentrations. I would like to run these
tests throughout the growing season, in early
spring, late June, mid-summer and fall. These
same physiological characteristics would also
be sampled from the larger tagged fish in the
fall. I am also interested in looking at some
indirect measurements of feeding with the intention
of expanding on a bioenergetics model.
The second aspect of my research involves evaluating
the exercise performance and fitness between the
two groups of bass. I am interested in
examining the ways in which the two groups respond
to stress in an ecological consequence (such as
swimming away from predators or chasing prey),
as well as in situations of exhaustive exercise
(such as an angling event). These experiments
would be conducted in a laboratory using a respirometer,
and would involve exercising the fish at different
rates and with varying periods of recovery. Physiological
measurements will include: muscle lactate, lactate
dehydrogenase, tissue energy stores, enzymes,
and hormones. It would also be interesting to
contrast the swimming ability and the active metabolic
rate of the two groups of fish (linking the field
and laboratory studies).
These proposed studies would help to establish
some baseline information to compare fish from
the two levels of angling vulnerability.
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