Eurasian Collared Dove – An Invasive Species

Eurasian Collared Dove
Eurasian Collared Dove

After seeing beautiful, large doves at various locations I travel to often here in Texas, I did not know what species they were. When flying they have a distinctive “caw” like sound. About a month ago an opportunity afforded me to capture a photo of one. The photograph revealed a new species to me – the Eurasian Collared dove (Streptopelia decaocto).

After talking about this species a few days ago with a fellow scientist, I decided to investigative more about this bird. What I discovered is this species of dove is one we all should be more watchful of on many levels here in Texas. While this dove is striking, it’s not native to Texas or this continent. The Eurasian Collared dove is an invasive species. Larger than native mourning doves this bird is distinctive due to the half black collar around its neck and its loud “caw, caw” like sound when they fly, not the typical cooing sound we are so used to hearing.

First reported in 1995 by birders in Texas, these species are native to the Indian subcontinent and expanded their range into Europe in the early 1900s. Then they were brought to Nassau in the Bahamas from the Netherlands in the early 1970s as captive species, some escaped, populated the other islands and eventually found their way to Florida in the late 1970s. From there they began migrating and expanding across the U.S.

Characteristic wise these doves are highly territorial and watch for intruders from high vantage points like utility poles or trees. During nesting adults are aggressive, flying at intruder’s or nest predators, delivering blows with their wings.

The first conservation concern is based on them being successful colonizers and breeders, is that they may be competing with native North American doves, as some scientists have theorized. These nonnative doves also have the potential to discourage other avian species from using bird feeders, and may aggressively defend these food sources, chasing other birds away.

The second conservation concern with these doves is that they can also carry the protozoan parasite, Trichomonas gallinae that can potentially spread to native doves at feeders or birdbaths. While T. gallinae is a cosmopolitan parasite of pigeons and doves, other birds may also become infected, especially if raptors eat them. This parasitic disease of young birds, its severity depends on the susceptibility of the bird and on the pathogenic potential of this parasite. Adult birds that have recovered from infection may still carry the parasite becoming resistant to reinfections. The parasite creates lesions in the birds’ mouth or their esophagus and prevents ingested seeds from reaching the stomach causing the bird to regurgitate food items that now become contaminated. Water sources become diseased by contact with the contaminated bill and mouth. Thankfully, there is no known health threat to people or mammals.

In Texas, the Eurasian Collared dove has been documented in 134 of the 254 counties. I know its in Bailey, Foard, and Lubbock counties. From a conservation standpoint what are your options if you have these doves on your property? If you own ranch land or other property in Texas and want to control their population to protect native species you need to abide by Texas’ hunting regulations. Policies concerning the Eurasian Collared dove are the same as for feral pigeons (Rock doves). A hunting license is required and there is no closed season or bag limit. Local restrictions concerning discharge of a firearm do apply so make sure you check with your local sheriff’s office before taking measures to choose to cull these populations on your property. If you live in another U.S. state that has Eurasian’s and have a conservation concern check with your state’s hunting regulations and local law enforcement before taking any actions towards these birds.

Another cautionary note if you have bird feeders on your property and decide to cull, take the extra safety precautions, clean all the feeders and water sources to protect other native birds you are feeding and watering.

It’s sad this gorgeous dove is a nonnative species. However, protecting our native wildlife is the number one priority.

Information sources:

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0111510

http://www.dallasnews.com/sports/more-sports/outdoors/20140830-invasive-species-the-eurasian-collared-dove-taking-over-texas.ece

https://tpwd.texas.gov/landwater/land/habitats/high_plains/upland_game/dove.phtml

http://www.texasinvasives.org/animal_database/detail.php?symbol=22

http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex4444

Click to access trichomonosis-fact-sheet-garden-wildlife-health.pdf

Click to access chapter_25.pdf

Photograph – © Christena Stephens Photography

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