Eurasian Collared-Dove

The Eurasian Collared-Dove (Streptopelia decaocto) was first released in the New World on the island of New Providence, in the Bahamas. In the mid-1970s, a local breeder was burglarized and a few of his birds escaped, after which the breeder released his remaining stock of about 50 birds1.  Since its introduction, this dove has spread quickly across the North American continent.

This is an animated map made from Christmas Bird Count data of Eurasian Collared-Dove sightings from 1987 through 19972.
eucdovani

The northwestern spread of this non-native species made it to my yard a few years ago. Click on photos for full sized images.

Eurasian Collared-Dove

The following maps I created on eBird show the dramatic growth in the spread of the Eurasian Collared-Dove from 2002 to 2014. This first map is data from 2002 through 2003.

Eurasian Collared-Dove Expansion

The lightest shade of lavender coincides with a 0 – 2% frequency of sightings, the next darker shade 2 – 10%, the next 10 – 25%, the next 25 – 40% and the darkest (almost black) shade is a 40 – 100% occurrence of the species.

This next map is data from 2007 through 2008.

Eurasian Collared-Dove Expansion

And the last one shows the stats from 2013 to the present.

Eurasian Collared-Dove Expansion

In North America and the Caribbean, they are found mostly in suburban, urban, and agricultural areas where grain, roost, and nest sites are available. They feed from grain storage and spillage areas, livestock yards, and bird feeders.

Both the juvenile Western Scrub-Jay and the Eurasian Collared-Dove were both a bit surprised to see one another at my platform feeder at the same time. Note the square tail on the Collared-Dove. A good field mark that differentiates it from the Mourning Dove, which has a pointed tail.

Eurasian Collared-Dove and Western Scrub-Jay

I’m including this photo to show the white terminal band of the undertail which is most conspicuous in flight.

Eurasian Collared-Dove

I am always alarmed when I see rapid expansion of a non-native species of any kind. They often tend to displace native species, whether they be plant or animal.

Eurasian Collared-Dove

David Bonter, Benjamin Zuckerberg and Janis Dickinson of the Cornell Lab of Ornithology believe that studying the relationships among introduced species, their preferred habitats, and native species, can be important for predicting the effects of invasions like this on native populations. They studied the relationship between collared-dove abundance and the abundance of other dove species in the study area, anticipating a negative effect on established species following the introduction of a potential competitor.

I was pleased to discover that contrary to their expectations, the site-level abundance of four other dove species all increased with collared-dove abundance throughout the sampling period3 rather than decreasing.

Eurasian Collared-Dove

Like most dove species, Eurasian Collared-Doves are prolific breeders. In warm climates they can breed year round. In Florida nesting has been reported in every month except January1. They usually lay two eggs per clutch and most often, successive clutches will be laid while adults are still attending fledglings!

This graph created by the Audubon Society from their Great Backyard Bird Count data is rather striking. You can see that their numbers are increasing faster as time goes on.

Eurasian Collared-Dove Expansion

This video explains the rapid invasion of the Eurasian Collared-Dove pretty well I think 😉  If you haven’t seen them in your area yet, you probably will soon.

httpv://youtu.be/bzUfM1ok-_s

Referfences: 1Birds of North America Online, 2Birdsource, 3Invasive birds in a novel landscape: habitat associations and effects on established species

Invasive Species WeekHere at 10,000 Birds 20 July – 26 July is Invasive Species Week. We use the term “Invasive Species” in the broadest sense, to encompass those invasive species that have expanded beyond their historical ranges under their own power, by deliberate introduction, or by unintentional introduction. The sheer number of species that have been shuffled around on our big earth is impressive, though we will be dealing with the smaller sample size of invasive avians and other invasives that effect avians. Nonetheless, this week will be chock full of invasive species. So batten down the hatches, strap on your helmet, and prepare to be invaded! To access the entire week’s worth of content just click here.

Written by Larry
Larry Jordan was introduced to birding after moving to northern California where he was overwhelmed by the local wildlife, forcing him to buy his first field guide just to be able to identify all the species visiting his yard. Building birdhouses and putting up feeders brought the avian fauna even closer and he was hooked. Larry wanted to share his passion for birds and conservation and hatched The Birder's Report in September of 2007. His recent focus is on bringing the Western Burrowing Owl back to life in California where he also monitors several bluebird trails. He is a BirdLife Species Champion and contributes to several other conservation efforts, being the webmaster for Wintu Audubon Society and the Director of Strategic Initiatives for the Urban Bird Foundation. He is now co-founder of a movement to create a new revenue stream for our National Wildlife Refuges with a Wildlife Conservation Pass.