Amplification of Black Vulture (\u3ci\u3eCoragyps atratus\u3c/i\u3e) DNA from regurgitated food pellets

Studies that rely on noninvasive collection of DNA for birds often use feces or feathers. Some birds, such as vultures, regurgitate undigested matter in the form of pellets that are commonly found under roost sites. Our research demonstrates that regurgitated pellets are a viable, noninvasive source of DNA for molecular ecology studies of vultures. Our objectives were to amplify 5 microsatellite loci designed for distinguishing Turkey Vultures (Cathartes aura) and Black Vultures (Coragyps atratus) in a single, multiplexed PCR, and to determine how long the target nuclear DNA persists after a vulture pellet is regurgitated and exposed to the environment. We collected pellets from captive Black Vultures and placed them in an outdoor aviary for a maximum estimated total of 12, 24, 36, or 48 h. We swabbed pellet surfaces for extraction and amplified vulture DNA using the panel of markers. All amplified alleles fell within predicted ranges of Black Vultures for all 5 loci, supporting the use of this microsatellite panel for vulture species identification. Overall amplification success for samples collected 0–12 h after regurgitation was 82.3%. Pellets collected 12–24 h, 24–36 h, and 36–48 h after regurgitation had only 18%, 10.2%, and 4.5% amplification success, respectively, which may have been due to a rain event. Our approach will be useful for noninvasive genetic sampling targeting nuclear DNA. These results should encourage noninvasive genetic sampling studies of other species that regurgitate pellets, such as raptors, water birds, or shorebirds

Industrial Hemp as a Resource for Birds in Agroecosystems: Human–Wildlife Conflict or Conservation Opportunity?

Industrial hemp (Cannabis sativa L.; hemp) is an emerging crop in the United States with little known about bird use or the potential for birds to become an agricultural pest. We identified birds associated with hemp fields, using repeated visits to oilseed plots in North Dakota, USA (n = 6) and cannabinoid (CBD) plots in Florida, USA (n = 4) from August to November 2020. We did not control for plot area or density; our observations were descriptive only. We observed 10 species in hemp, 12 species flying over hemp, and 11 species both foraging in and flying over hemp fields in North Dakota. In Florida, we observed 4 species in hemp, 5 species flying over hemp, and 4 species exhibiting both behaviors. When we observed birds in hemp, we found them perched in the canopy or foraging on the ground. Counts were highest in oilseed and lowest in CBD varieties. The Florida sites were mainly CBD varieties, which explains lower species diversity and raw counts of birds given the lack of seeds produced. Maximum raw counts of the most common birds (mourning doves [Zenaida macroura] = 116; house finches [Haemorhous mexicanus] = 53; and American goldfinches [Spinus tristis] = 40) using very small fields (116–324 m2) in North Dakota suggest oilseed hemp could suffer yield losses but potentially benefit farmland bird conservation and act as a decoy crop to protect other commodities (e.g., sunflower [Helianthus annuus L.])