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From the field

I hope you enjoyed this week’s posts! It has been fun working with the many great people who’ve helped make this project happen, and it’s exciting to consider all the research and conservation possibilities that lie ahead. I’ve been focusing on Spotted and Barred Owl ecology, but next year I’m joining @cornellbirds to tackle the challenge of identifying the vocalizations of potentially hundreds of other species that are in the raw audio! Can anyone identify any species in that spectrogram? Photos by Kevin Wood, @whatbirdisthis, & me. #birds #wildlife #science #outdoors #ornithology #birdsong #birdcalls
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[Thanks, @cmmwood! If YOU are an AOS member and would like to be featured here for a week, please get in touch.]Barred Owls are more territorial than Spotted Owls, and having tagged both I can confirm that this aggression carries over to their behavior when handled. I was fortunate to occasionally work with Dennis Rock, who has a wealth of owl capturing experience. When a Barred Owl chomped down on his finger, he told me to just leave it because it would then be easier for me to finish tagging the bird! However, the next season when I took a full fist of talons to my palm, I definitely fixed the problem right away. Later that night we created gloves that provided some protection without impairing dexterity. Photos by @nkryshak. #ornithology #birds #owls #wildlife #science #conservation
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[Our thank to AOS member Connor Wood (@cmmwood), who's taking over this account for the week!]Two years of acoustic surveys showed that the Barred Owl population had increased by a factor of 2.6, which was very concerning. We deployed GPS tags on ten individuals to test the possibility that the population estimates were inflated by a few highly mobile (and very vocal) individuals. All the birds we tagged displayed very stable territories, suggesting that the population had indeed grown between years. This represents a major challenge for Spotted Owl conservation in the Sierra Nevada. Photo courtesy of @u.s.forestservice. #ornithology #birds #owls #wildlife #science #conservation
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[Our thank to AOS member Connor Wood (@cmmwood), who's taking over this account for the week!]We deployed passive recording units designed and built by the Cornell Lab of Ornithology (@cornellbirds). Once the raw audio data was back at base, we compressed the files and copied them onto two sets of hard drives — better safe than sorry! This is a boring part of the job, but when you’re collecting 30 TB of data each year, careful management is really important. We then scanned the data for the vocalizations of Spotted and Barred Owls, and those results allowed us to develop multi-season occupancy models for both species. Picture three is a spectrogram, or visual representation of sound, of a Spotted Owl “four-note” call. Photos by me. #ornithology #birds #wildlife #science #owls
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[Our thank to AOS member Connor Wood (@cmmwood), who's taking over this account for the week!]To assess the status of the Sierra Nevada Barred Owl population, we conducted passive acoustic surveys across over 6,000 square kilometers of mountainous terrain in the Lassen and Plumas National Forests. This meant some great campsite views and, for better or worse, accessing some sites with fatbikes! Photos by me. #ornithology #wildlife #science #ecology #owls #california
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[Our thanks to AOS member Connor Wood (@cmmwood), who's taking over this account for the week!]Over the last century, Barred Owls (first picture) have expanded from their historic range in eastern North America and are now found throughout the Pacific Northwest and northern California. Long-term studies have shown that they outcompete their smaller cousin, the Spotted Owl (second picture). Barred Owls have been documented sporadically in the northern Sierra Nevada since the late 1980s, but until my teams conducted our acoustic surveys, there was no concrete data on their density and distribution in the region. Photos by @dannyhofstadter and myself. #ornithology #birds #wildlife #owls #science #conservation #ecology
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[Our thanks to AOS member Connor Wood (@cmmwood), who's taking over this account for the week!]
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