January 17, 2011
No species of bird has colonized North America at the speed with which the Eurasian Collared-Dove (Streptopelia decaocto) has marched across the continent. First found nesting just south of Miami, Florida, in 1982, this non-native dove has rapidly adapted to human-altered environments from Florida to Alaska. FeederWatch has provided a crucial source of information on this invasion and insight into how this invader may be affecting populations of native doves.
Researchers at the Cornell Lab of Ornithology recently focused on reports submitted by444 FeederWatchers in Florida to better understand the collared-dove invasion. First, they were interested in examining the potential impact of collared-doves on other dove species such as the Mourning Dove, White-winged Dove, and Common Ground-Dove. Many invasive species have a negative impact on native species, particularly species that are similar to the invader. Contrary to expectations, however, researchers found that the abundance of native dove species was generally greater at sites with collared-doves than at sites without collared-doves.
Second, researchers were interested in identifying which types of habitats the collared-doves were using. Linking satellite-derived land cover data with FeederWatch data gathered from 1999 to 2008, the researchers found that collared-doves were more likely to occur in landscapes that had been highly-modified by human activity than in forested landscapes. Many invasive species are successful because, like the collared-dove, they can readily adapt to suburban life.
What’s next for the Eurasian Collared-Dove?
The species continues to spread across the continent and grow in abundance (click on map above to see an animation of the range expansion). The doves naturally disperse in a northwesterly direction, so the most rapid range expansion has taken place along a southeast-to-northwest path from Florida to Alaska. It appears to be only a matter of time, however, before the gaps in the species’ range in the Midwest and Northeast are colonized. FeederWatch staff will keep an eye on interactions between collared-doves and native species as the invasive species continues to colonize different regions and environments. We may ultimately find that collared-doves do compete for food with other dove species in colder regions in winter.
If you would like to contribute data on the spread of Eurasian Collared-Doves, please consider joining Project FeederWatch. The only way we can track the spread of this species is with data submitted by FeederWatch Participants – so sign up to contribute! Please note that commenting on this post with Eurasian Collared-Dove observations will NOT contribute to data!
Did you find a Eurasian Collared-Dove nest? Check out our post on monitoring Eurasian Collared-Dove nests!
Source: Bonter, D. N., B. Zuckerberg, and J. L. Dickinson. 2010. Invasive birds in a novel landscape: habitat associations and effects on established species. Ecography 33:494-502.