Transcript Fessler - York College of Pennsylvania

Behaviors of Minnows (Cyprinidae) in Response
to Alanine and Histidine in a Field Setting
Katie Fessler, Department of Biology, York College
Introduction:
Through gustation and olfaction, fish detect
chemical cues in their environment that may
cause behavior changes. Scientists test
these abilities of fish in the laboratory by
exposing them to amino acid solutions and
identifying specific responses. The
laboratory has controlled conditions at all
times to ensure the behavior comes only
from the administered solution.
Behaviors Documented:
Methods:
Locate significant aggregation of minnows
Place solution distribution pipe, Position camera,
Administer red dye, Measure plume created
AquaVu
underwater camera
Pipe to evenly release
amino acid solution
What happens in a natural stream?
To answer this question, the minnows
swimming in Tyler Run on the York College
campus were presented with various
concentrations of two amino acids: alanine
and histidine. Past laboratory experiments
have focused on catfish, trout, and
zebrafish, whereas my research examined
the reactions of minnows, including
blacknose dace and creek chub.
According to laboratory research, when
trout detect alanine through smell, they are
attracted to the source; when they detect
histidine, they are repelled.
1. Number of minnows
2. Darting
• Considered an attracting odor
if minnows dart toward solution
• Considered a repelling odor
if minnows dart away from solution
Results:
Alanine:
•According to paired t-tests, there was no
difference between how the minnows reacted to
the control in contrast to the alanine solution.
Histidine
•According to paired t-tests, there was no
difference between how the minnows reacted to
the control in contrast to the histidine solution.
Leave area undisturbed for 30 minutes and
use creek water to make 10-8, 10-7, and
10-6 M solutions of histidine or alanine
1. Videotape for 1 minute
2. Administer solution
Number of Minnows (%)
Control vs. 10-8 M Concentration of Histidine
Alanine vs. Histidine
•When comparing darting behavior and number
of fish between alanine and histidine, there was
no difference.
Figure 2. A paired t-test calculated p=0.0568, demonstrating
that there was not quite a difference in the number of
minnows during the 10-8 M histidine test in contrast to the
control test. The number of minnows is in terms of
percentage so it was possible to average all replicates
regardless of the amount of fish tested each day.
Histidine vs. Alanine: Number of Minnows (%)
at 10-7 M Concentration
Number of Minnows (%)
Control vs. 10-6 M Concentration of Alanine
3. Videotape for 3 minutes
Hypothesis:
At high enough concentrations, minnows
will show the same reactions as trout in a
field setting. Alanine will cause an increase
in the number of minnows within the field of
view of the camera while histidine will cause
an evacuation.
Test Subjects:
Eastern Blacknose Dace (Rhinichthys atratulus)
http://fish.dnr.cornell.edu/nyfish/Cyprinidae/e_blacknose_dace.jpg
Creek Chub (Semolitus atromaculatus)
http://fish.dnr.cornell.edu/nyfish/Cyprinidae/creek_chub.jpg
4. Wait 15 minutes
Order of solutions for Steps 1-4:
a. 2 L creek water control
b. 1 L 10-8 M solution, 1 L creek water
c. 1 L 10-7 M solution, 1 L creek water
d. 1 L 10-6 M solution, 1 L creek water
e. 2 L creek water control
Figure 3. A paired t-test calculated p=0.4322, demonstrating
that there was no difference in the number of minnows
during the 10-7 M alanine test in contrast to the 10-7 M
histidine test. The number of minnows is in terms of
percentage so it was possible to average all replicates
regardless of the amount of fish tested each day.
Conclusions:
Repeat 12 times using alanine
Repeat 8 times using histidine
Analyze tapes and
quantify behaviors
Figure 1. Visually, it appears that the minnows were able
to detect alanine, but a paired t-test calculated p=0.9399,
meaning that there was no true increase in the number of
minnows once the solution was administered. The
number of minnows is in terms of percentage so it was
possible to average all replicates regardless of the
amount of fish tested each day.
If the minnows could truly detect alanine
or histidine, the many variables in a field
setting were too overpowering to yield
any significant statistical results.
Acknowledgments:
I would like to thank Dr. Landis for allowing me to use all of his video equipment
and devoting countless hours to helping me use the equipment out at the creek.
I would like to thank Dr. Rehnberg for his guidance throughout this entire project.
I would also like to thank Dr. Kleiner for disassembling the man-made dam in
my test area, Dr. Thompson for the donation of his television, Christina Johnson
and the remainder of the Biology Department faculty for all much needed help
and encouragement!