Corvus corax (Common Raven, hereafter Raven) was historically ubiquitous throughout much of North America, but persecution and habitat loss after European settlement resulted in range reduction and population decline across much of the eastern US. Increasing numbers of confirmed sightings of Ravens in the eastern US over the past 70 years suggest rapid regional recolonization, particularly in central and southern Appalachia where, in many states, Ravens were thought to be extirpated or at least highly range-restricted. We compiled 64,611 Raven observations from multiple public and private sources across Appalachia between 1950 and 2016 and performed spatial analyses to characterize regional recolonization trends. The Appalachian Mountain range has served as both a refugium for Ravens during the late 19th and early 20th centuries and a regional source population for range expansion between 1950 and 2016. Ravens are now common in the mountainous areas of Appalachia and have recently expanded their range into lower elevations, including the successful recolonization of 4 states: Alabama, Kentucky, Ohio, and Tennessee. Spatial analyses demonstrated a 40% increase in the Raven's apparent geographic range in central and southern Appalachia, which now spans at least 470,380 km2. We present an updated map detailing current Raven distributions in central and southern Appalachia and review potential habitat, interspecific, and trophic factors aiding range expansion for Ravens.
|Number of pages||16|
|State||Published - May 2019|
Bibliographical noteFunding Information:
We extend our gratitude to the agencies and organizations throughout Appalachia who offered us access to their avian sighting databases and to the many professionals and private individuals who offered their time to communicate sighting information. We are thankful for the diligent work of the state ornithological societies of Georgia, Kentucky, Maryland, Ohio, Pennsylvania, Tennessee, and Virginia and of the American Birding Association, Brooks Birding Club, and Carolina Birding Club in documenting sightings in regional publications. Christmas Bird Count and Great Backyard Bird Count data were provided by the National Audubon Society and through the generous efforts of Bird Studies Canada and countless volunteers across the western hemisphere. We are also grateful to the thousands of participants who annually perform and coordinate the US and Canadian Breeding Bird Survey. For making information regarding Raven museum specimens publicly available via VertNet, we thank the Academy of Natural Sciences of Philadelphia, Carnegie Museum of Natural Sciences, Florida Museum of Natural History, Macaulay Library, National Museum of Natural History at the Smithsonian Institute, New York State Museum, North Carolina Museum of Natural Sciences, and Western Foundation of Vertebrate Zoology. We are further grateful to the proprietors of the online databases Avian Knowledge Network and Birding on the Net. We thank E. Hackworth for technical assistance with database management. This work is supported by the National Institute of Food and Agriculture, US Department of Agriculture, McIntire-Stennis project #KY00903.
© 2019 Humboldt Field Research Institute. All rights reserved.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics