Using Noninvasive Genetics for Estimating Density and Assessing Diet of Urban and Rural Coyotes in Florida, USA

Coyotes (Canis latrans) are expanding their range and due to conflicts with the public and concerns of Coyotes affecting natural resources such as game or sensitive species, there is interest and often a demand to monitor Coyote populations. A challenge to monitoring is that traditional invasive methods involving live-capture of individual animals are costly and can be controversial. Natural resource management agencies can benefit from contemporary noninvasive genetic sampling approaches aimed at determining key aspects of Coyote ecology (e.g., population density and food habits). However, the efficacy of such approaches under different environmental conditions is poorly understood. Our objectives were to 1) examine accumulation and nuclear DNA degradation rates of Coyote scats in metropolitan and rural sites in Florida to help optimize methods to estimate population density; and 2) explore new genetic methods for determining diet of Coyotes based on vertebrate, plant, and invertebrate species DNA identified in scat. Recently developed DNA metabarcoding approaches make it possible to simultaneously identify DNA from multiple prey species in predator scat samples, but an exploration of this tool for assessing Coyote diet has not been pursued. We observed that scat accumulation rates (0.02 scats/km/day) did not vary between sites and fecal DNA amplification success decreased and genotyping errors increased over time with exposure to sun and precipitation. DNA sampling allowed us to generate a Coyote density estimate for the urban environment of eight Coyotes per 100 km2, but lack of recaptures in the rural area precluded density estimation. DNA metabarcoding showed promise for assessing diet contributions of vertebrate species to Coyote diet. Feral Swine (Sus scrofa) were detected as prey at higher frequencies than previously reported. We identify several considerations that can be used to optimize future noninvasive sampling efforts for Coyotes in the southeastern United States. We also discuss strengths and drawbacks of utilizing DNA metabarcoding for assessing diet of generalist carnivores such as Coyotes

European Starling Preferences for Bait Substrates Used In DRC-1339 Applications

Additional bait substrates for the avicide, DRC-1339 Concentrate (3-chloro-4- methylaniline hydrochloride), could provide USDA/Wildlife Services with more flexibility when managing nuisance populations of European starlings (Sturnus vulgaris) at livestock facilities. From January 11 to 21, 2008, we conducted 11 2-choice preference tests with 6 bait types at a feedlot in central Kansas. The baits included cracked corn mixed with lard (2 concentrations), 2 forms of distiller’s grain (wet powder and pellets), 2 types of livestock feed (calf-starter pellet and sweet-feed mix), and a custom-produced poultry pellet (carrier pellet) made by USDA specifically for baiting starlings. We evaluated bait preference using 95% confidence intervals of mean differences in feeding rates among 4 cages of starlings with 6 starlings per cage. Starlings preferred the carrier pellets. Contemporaneous with the cage tests, we offered the same baits to free-ranging starlings at open-feeding platforms positioned within the feedlot. Free-ranging starlings also favored carrier pellets over other baits. Use of carrier pellets at livestock facilities where starlings have numerous food sources may be more cost-efficient than less-expensive baits (e.g., cracked corn or distiller’s grain) because of its higher acceptance by free-ranging starlings