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Fieldwork was conducted in a humid
dry rain forest in Mastatal, Costa Rica during the middle of
July 2005. Mid-July marks the beginning of mating season for
the D. auratus as males become more active and aggressive
in their search for potential female mates (Summers et al. 1999).
D. auratus will often use low hanging branches and
shrubs as a place to call to these mates (Walls 1994). Three
locations; A, B and C, were chosen on the property of Rancho
Mastatal Environmental Learning and Sustainable Living Center,
Retreat and Lodge located in the last virgin rainforest of Costa
Rica’s Puriscal County.
The locations were chosen based on proximity to a river and
small stream. One study found D. auratus prefer secondary
forest for habitat (Schafer 1999). All locations contained heavy
leaf litter, fallen branches, and low hanging shrubs. Leaf litter
is also used by the D. auratus to lay their eggs (Mattison
1987). The underbrush was relatively clear and easily accessible.
Each location was 25 square meters in area and contained one
large tree measuring at least eighteen inches in diameter. Access
to these sites was by a trail located behind the main house.
In order to determine if a location close to a moving water
would result in higher numbers of D. auratus we positioned
site C so that one side of the area bordered a small river.
Next, site B was positioned 9 meters from a stream. Finally,
site A was positioned 18 meters from the stream, thus creating
a consecutive line of test locations with each measuring 9 meters
further from the moving water than the previous location.
Building the sites required 3 basic tools. A meter tape used
to measure distance from the research sites to the river and
streams and for building identical size research site areas.
A compass was used for determining direction and angle of corners.
Metal spikes with orange flags were used for stationary ground
markers.
4 different instruments were used while conducting the research
within the locations. A telescopic snake hook was the primary
choice for turning over leaf litter and fallen branches. A stopwatch
was used to keep track of time spent in each location. A note
book and pencil were use to record data, and various photographic
equipment was used to document images of the sites and the D.
auratus they contained.
Each site measured five meters by five meters. We used a meter
tape to measure exact dimension of each site. A compass was
used in conjunction with the meter tape to ensure the site was
a perfect square. Each corner of the site was tagged with an
orange flag attached to a metal spike.
The sites were checked once in the morning and once in the evening
for three days. Each site was checked in consecutive order A,
B, and C with no more than 10 minutes at each site looking for
D. auratus. The exact time research began was documented
by researcher one.
Upon arriving at each site, researcher one documented the time
of day and placed the ground thermometer at the edge of the
site. The air thermometer was hung from vegetation above the
ground thermometer. Researcher two would then walk north to
south in the site visually scanning a one meter wide path while
using a telescopic snake hook to turn over all leaves and vegetation.
Trees and small vertical vegetation were visually inspected
up to one meter in height. While researcher two inspected the
ground researcher one watched the complete site for any D.
auratus moving in site due to disturbance of researcher
two. Data was written in a field journal as it was collected.
Once the site was inspected for D. auratus activity,
ground and air temperature readings where documented by researcher
one. Weather conditions were also noted by visual assessment.
To prevent biased results researchers rotated duties, the researcher
in the morning completed researcher one duties, with reversed
duties in the evening. Duties were again reversed the following
day.
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