Bird bandits, volcanic escape: Tropical doves with wild backstory invade Alberta

An invasive dove is making its way from the sunny beaches of the Caribbean and invading Alberta's icy cities.

With a flash of white tail feathers and a flurry of dark-tipped wings, the population of Eurasian collared doves continues to grow throughout the province.

Once exceedingly rare, the doves are becoming an increasingly common sight, especially in central and southern Alberta.

"The numbers have been going up exponentially," said Dave Ealey a biologist and an organizer with the Christmas bird count. "I was really surprised to discover how common they have become in Alberta."

• Red Deer man punches cougar at Tim Hortons to save dog
• CBC Edmonton's most memorable animal stories from 2016

In 2003, four of the plump, cooing creatures were detected in the province during the nationwide bird census. In 2015, more than 1,100 of the birds were found across Alberta.

Roughly the size of a pigeon, the doves are a tawny beige with a delicate collar of black feather that wraps around the back of their necks.

"It looks like a dove," Ealey said. "They're smaller and slimmer than what we refer to as a rock pigeon, and that's the one people normally see.

"I think the collared doves are little bit more refined."

 Though you've likely seen them perched on telephone poles or pecking away at your backyard bird feeder, the species is completely foreign to the Canadian climate.

Originally from sub tropical Asia and Europe, the doves came to the country by way of the Bahamas, where a small number escaped captivity in 1974. As the legend goes, a breeder of exotic pets was robbed and during the burglary, a few of the birds escaped their cages.

After the robbery, the shop owner decided to release the remainder of his flock, 50 birds, into the wild.   

Although his motives remain mysterious, the robbed businessman had unwittingly introduced the species to North America — and the birds soon multiplied.

In another strange turn of events, more of the doves were set free on the island of Guadeloupe when a volcano threatened eruption in 1976.

By the 1980s, the escaped birds had made their way to Florida before rapidly colonizing most of the United States.

"If you look at the historical records, you can see the spread has just continued from that corner, from Florida, up towards the midwest and North America," Ealey said. "This is a quite a very interesting story, that in such a short period of time they've become established and have spread from that location." 

Ealey says Alberta's urban habitat has provided ample food and shelter for the doves.

They feed on bird seed and backyard plants and nest in heavily treed city parks. They also don't have to compete with their cousins, the grey rock pigeon. These common cliff-dwelling creatures prefer bridges, overpasses and high building ledges.

"The rock pigeon is taking advantage of one kind of habitat and the Eurasian collared dove is taking advantage of another," Ealey said. "It says something about the character of the bird and its adaptability."

• Sharks, 'cougars' and bears, oh my!: Top 5 animal stories of 2016

It's hard to predict how the invasive species will affect Alberta's native plants and animals, but their effect on other North American habitats has been fairly mild, Ealey said.

He hopes the doves don't ruffle too many feathers as they make a new home in Alberta. 

"It's really a success story. Here is a bird that has taken advantage of a niche, a habitat, that really wasn't being used," Ealey said. "And It's not just Alberta, this is across North America."