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Students who work on this
project are involved in field data collection and the
development (modification) of population models which describe the dynamics
of the green tree frog. Below we give a summary of what the 2003-2005 team worked on.
- Weekly Catching of Tadpoles at National
Wetlands Research Center - The tadpoles caught are then dyed with a
neutral red solution and released back to the location in which they
were caught. The next day, a repeat tadpole collection is conducted,
and recapture percentages are calculated.
- Frog Capture by Pipe - Once a week, the students go to the field site to
catch green tree frogs from inside numbered PVC pipes set up around
the ponds. If a frog is already marked with an
alpha-numeric tag, its number is recorded, along with its length and
location, and the frog is released back into the pipe. If a frog
is not already marked, then the frog is measured, marked with a new
alpha-numeric tag, and released back to its pipe.
- Frog Capture by Hand - The mark-recapture
technique used for pipe capture is also used during hand-captures
conducted weekly after sunset.
- In addition, 16 green tree frogs, caught at
an outside location, are being kept in an aquarium at the NWRC.
These frogs were all marked with alpha-numeric tags, and are kept in a
controlled location in order to test the longevity of the tags.
- The students used statistical methods to
estimate weekly population size from the data collected in the year
2004. These results have been written up and submitted for publication.
- Mathematical Models and MATLAB - Students
developed a preliminary mathematical model which describes the dynamics
of this frog population. Finite difference approximations to the
solution of this model were computed using MATLAB. Currently the model
is being analyzed and the results will be written in a form of research
manuscript.
- Simulation Models using STELLA - As an
alternative approach to the mathematical models, the students have
developed a preliminary simulation model of the
green tree frog population at the NWRC using STELLA.
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