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Contrary to our hypothesis, D. auratus was not found
in greater quantities closer to a river or small stream. Site
C, located directly on the small river, resulted in zero D.
auratus being sighted. This could have been due to lower
ground and air temperature compared to sites A and B resulting
from a moderately sized waterfall 20 meters from sample site
C. The off spray from the cool river water cooled both the
land and air.
Temperatures above 26 degrees Celsius combined with clear
skies resulted in no D. auratus sightings at A, B
or C research sites. These results are similar to a study
conducted by Jaeger et al. (1981) with findings of limited
D. auratus activity around noon with clear skies. The
only exception in our study occurred at site B in the AM of
July 19, 2005 when 2 frogs were found. A possible reason for
this exception is a moderate rain shower that had lasted throughout
the night resulting in lower temperatures and sunshine limited
to only a full hour prior to our AM field test.
All three sites contained heavy leaf litter providing favorable
habitat for D. auratus because of the leaf’s
ability to retain moisture and harbor insects. Throughout
the searches many types of arthropods were spotted. Arthropods
are a primary source of food for the D. auratus (Darst
et al. 2004). We speculate food was not a limiting factor
in site C.
If the sun is a major factor in D. auratus activity,
deforestation may have a detrimental effect on the population.
Without trees, ground and air temperature will be considerably
higher than 26 degrees Celsius experienced in this project.
The Dendrobates family of poisonous frogs is continually being
tested for possible medicinal purposes for humans. If
D. auratus becomes extinct, we may miss possible cures
for pain and disease.
Future studies are necessary to be able to make absolute conclusions….
Sample sites should be larger in size to obtain a density
measurement. Sites should also be farther away from rivers
and streams to determine if distance is a factor. The use
of a canopy densitometer at all locations would be required
to determine in direct sunlight limits daily activity of D.
auratus. Future studies should document and tag all D.
auratus found to determine territory boundaries.
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