Transcript Frog call analysis - Firestone Reserve

Firestone Center for Restoration Ecology
Barú, Costa Rica
Summer 2007
Alicia Hill
Purpose of Study
 Expand the comprehensive list of all anuran species
present on the reserve
 Determine anuran diversity and density at each pond
during dusk time
 Obtain recordings of individual species mating calls
 Track changes in anuran diversity on the reserve from
the previous year
Why study frog diversity?
 Indicators of an ecosystem’s health
 Ability to track the status of the restoration progress
on the reserve
Previous Study
 Summer 2006, baseline of anuran
species on the reserve
 14 species were identified,
6 species mating calls were recorded
 A. callidryas was dominant at dusk,
followed by H. microcephala and
H. ebraccata
 One pond analyzed
Methods
 Recorded mating calls at night using an automated
frog logging system
 Took six 10 minute recordings every 50 minutes
 In this study, only the first 10 minute recordings (dusk
time) were analyzed
Collection Sites
 Four man-made ponds on the reserve
 Each pond isolated from one
another
 Ponds differ in size, surrounding
flora, and organisms living in
the water
Basilisk Pond
Data Analysis
 Identified each anuran species from the recorded data
at each pond
 Audacity audio editor and Sigview Signal Analyzer
 Calculated the average calls per minute(n=10) for each
species
180
Average
anuran
frequencies± at
four
ponds
at 6 PM
Average anuran
call call
frequencies(mean
SE;the
n=10)
at the
four ponds
at 6 PM
Average Call Frequency (calls/min)
160
140
120
100
Duck
80
Creek
60
Basilisk
Frog
40
20
0
Anuran Species
Data Analysis of H. rosenbergi
Figure 1. Oscillogram of H. rosenbergi, average call frequency is 58 calls/minute
Data Analysis of H. rosenbergi
Figure 2. FFT of H. rosenbergi, dominant frequency at 0.47 kHz
Results
 The dominant species at this time throughout the
ponds were Agalychnis callidryas, Leptodactylus
pentadactylus, and Hypsiboas rosenbergi species
(Chi-square test, p<0.0001)
Other Conclusions
 Many Duck Pond anurans are mating
 Anurans doing well in/near bamboo
forest (Creek, Basilisk, Frog)
Summer 2008
 Continue recording at the ponds and track species
changes
 Search for more anuran species that have been
recorded at Hacienda Barú (e.g. Glass frogs)
 Expand time recordings to later in the night
Species List
Bufo haematiticus
Bufo Marinus
Eleutherodactylus fitzingeri
Leptodactylus pentadactylus
Bufo valliceps
Dendrobates auratus
Dendrobates granuliferus
Agalychnis callidryas
Hyla ebraccata
Hyla microcephala
Scinax elaeochroa
Smilisca phaeota
Eleutherodactylus bransfordii
Eleutherodactylus diastema
New Species 2007:
Agalychnis spurelli
Phrynohyas venulosa
Hypsiboas rosenbergi
Agalychnis spurelli
Phrynohyas venulosa
Hypsiboas rosenbergi
The prepollex , concealing the prepollical spine
Acknowledgments
 I would like to thank Dr. McFarlane and Keith
Christenson for their guidance and teaching
 Thank you to Al Binder, Keala Cummings, Sam Scott,
and Emily Shultz for their help.
Questions?