DETECTABILITY AND OCCUPANCY OF THE COMMON RAVEN IN CLIFF HABITAT OF CENTRAL APPALACHIA AND SOUTHEASTERN KENTUCKY

• Main Author: Felch, Joshua Michael
• Format: Others
• Published: UKnowledge 2018
• Subjects: Common Raven; Corvus corax; Detectability; Occupancy; Recolonization; Natural Resources and Conservation
• Online Access: https://uknowledge.uky.edu/forestry_etds/39; https://uknowledge.uky.edu/cgi/viewcontent.cgi?article=1040&context=forestry_etds

Nearly extirpated from the Central Appalachians, USA by the mid-1900s as a result of human persecution, loss of forests, and absence of large mammal carrion, remnant populations of common ravens (Corvus corax) have recolonized portions of their historical range. One such area of recolonization is southeastern Kentucky where the species is listed as state threatened. Southeastern Kentucky appears to have extensive suitable breeding habitat, but raven records remain relatively rare with sightings and a few nests being confirmed during the past three decades. Because little is known about local ecology or population status of this reclusive corvid in Kentucky, I assessed distribution and occupancy of ravens in available cliff habitat to quantify factors that affect detectability of ravens, identify landscape attributes important to raven breeding locations at multiple scales, and develop a protocol for monitoring occupancy of potential raven breeding habitats in Kentucky. Based on surveys of 23 cliff sites during 2009–2010, I found that ravens are highly detectable (p=0.90 (95% CI = 0.81–0.95)) at known occupied cliff sites, suggesting a survey effort consisting of two visits, each lasting one hour, will enable occupancy to be determined with 95% confidence. Using this and the habitat information associated with occupancy (cliff area and horizontal strata orientation), a monitoring protocol was developed and initiated in 2011 that should be useful to wildlife managers and land stewards interested in long-term monitoring, management, and conservation of common ravens in Kentucky’s cliff habitat.