Booth Id:
ANIM063
Category:
Animal Sciences
Year:
2021
Finalist Names:
Ebey, Karin (School: Los Alamos High School)
Abstract:
Climate change is causing precipitation and temperature patterns to change, and in response
species are undergoing phenological shifts, changes in reproduction timing. To explore the effects
of phenological shifts on the crocodilian response to climate change, a model was created using a
novel adaptation of the Lotka-Volterra equations. The model uses a time step of months, and
includes a crocodilian population and twelve other plant and animal species. Rainfall impacts the
ecosystem through the plants, and temperature affects plant growth and animal energy needs and
hatch rates. The model was validated by running with Louisiana rainfall and temperature data and
comparing the model outputs with measured alligator nest count data. As a baseline, variations in
the timing and magnitude of rainfall and temperature were examined. Populations increase when
there is more rainfall overall or available during the growing season and decrease when there is
less. Temperature changes mainly cause ectotherm populations to decrease due to suboptimal
temperatures for hatching. The effects of phenological shifts on the response to rainfall and
temperature changes were examined. Phenological shifts result in populations increasing if the
reproduction occurs at a better time in terms of prey availability and predator populations. However,
in general phenological shifts do not significantly alter the qualitative ecosystem response.
Species-specific phenological shifts at different rates or based on different cues do not strongly
affect other populations. Using the results of this model, a management program was designed
with recommendations to protect crocodilians and their ecosystems from climate change.
Awards Won:
Fourth Award of $500