Effects of captive rearing on vocal development of the Aga (Corvus kubaryi)

Andria Kroner Binghamton University

Report 1

Effects of captive rearing on vocal development of the Aga

Åga vocalizing during a rare moment with a clear view through the canopy.

I arrived on the island of Rota in mid-August and the new equipment arrived in perfect condition. Some Åga (Mariana Crow) pairs have just begun nesting, and this breeding season is looking like it will be a good one.

This season my study will be comparing the vocalizations of captive-reared young to those of wild-reared young. While I wait for the San Diego Zoo Global team to collect the first eggs and chicks for the captive rear-and-release program (scheduled for early October), I am beginning to collect behavioral observations and recordings of wild Åga with my handheld microphone for later characterizing vocalizations.

I have also begun to test out Kaleidoscope's clustering analysis on recordings made in Åga territories last summer using SM3 and SM4 recorders. I am very pleased with how well Kaleidoscope is performing and is able to find Åga vocalizations even with other background noise in the recordings. It even found vocalizations that I missed when scanning through spectrograms visually!

Very soon I will be recording Åga at their nests with the new external microphones and extra long 50m cables I was awarded, resulting in thousands of hours of audio by the end of the season. Using Kaleidoscope's clustering analysis to find and identify Åga vocalizations recorded at these nests should allow me to analyze a substantially larger dataset compared to what might be possible using other available software. I can't wait till the first wild nest recordings start rolling in!

Report 2

Effects of captive rearing on vocal development of the Aga

Hiding the external microphone among the vines near a nest.

Effects of captive rearing on vocal development of the Aga

Spectrogram of a 4-hour-old åga hatchling at feeding time in captivity.

Effects of captive rearing on vocal development of the Aga

A 20-day-old captive-reared åga nestling, also at feeding time.

As the Third Quarter grant recipients in 2017, we have now been able to begin the analysis portion of our first season of ultrasonic and acoustic data. For our collaborative project, this summer we have collected both acoustic and ultrasonic recordings at our study sites in Southeastern Massachusetts. This grant has allowed us to run our six months of calls through Kaleidoscope Pro. Over these last few months, a member of our team has attended a workshop run by Wildlife Acoustics and we all have learned how to apply Kaleidoscope Pro software. Our research team has just begun looking at our first season of recordings with less than 10% of our 2017 recordings analyzed.

Our goal for this project is to assess occupancies of bats and anuran taxa in Massachusetts protected and private areas and to analyze the overall soundscape for these sites. Two of our three field sites are located within Mass Audubon's Moosehill Wildlife Sanctuary (Sharon, MA) and a third, private site, in Bridgewater, MA. We deployed Wildlife Acoustics SM3BAT systems from May 2017 – October 2017 at the Mass Audubon sites. Along with learning the software ourselves, during the fall semester we began training two Undergraduate Biology majors enrolled in research credits. This has been the students' first true involvement in conducting scientific research.

Both of our SM3BAT hardware systems were fitted with ultrasonic and acoustic microphones. Since ending our field season in October, we have only been able to scratch the surface of our recordings; analyzing a couple hundred ultrasonic, bat calls. Non-ultrasonic, soundscape recordings have yet to be examined. In the coming semester, we along with our trained research students and new undergraduate students will begin acoustic analyses and continue cluster analysis on our ultrasonic recordings. Come March, our research team will begin the second field season.

Kaleidoscope Pro will continually be used moving forward with this project on bat and anuran taxa. Now that we have learned how to use this software, this spring we hope to complete analysis on our first season of acoustic recordings.

Wildlife Acoustics is proud to support wildlife conservation efforts

Merlin Tuttle's Bat Conservation Orginization for Bat Conservation Bat Conservation International Bat Conservation Trust Wildlife Habitat Counsil