Monday, March 10, 2014
By Herb Wilson
Tourist season is upon us again. On May 28, Maine hosted a visit by a Eurasian collared dove. This bird showed up at a feeder in Falmouth. It represents the first record of the species in the state of Maine.
A distinct black band, edged with white, reveals this handsome bird in Doug Hitchcox’s Falmouth yard to be the first Eurasian collared dove reported in Maine.
Doug Hitchcox Photo
Alas, this tourist did not tarry and was not seen subsequently.
From the picture taken by Doug Hitchcox, you can see this dove is a striking bird with a sandy-gray plumage and a distinct black band, edged with white, across the nape. The tail is squared off rather than pointed like the tail of a mourning dove. The call (koo-KOO-kook, with the second syllable accented) is distinctive.
As the name suggests, Eurasian collared doves are not native to North America. The arrival of the species in Maine is a long story with a few interesting twists.
Eurasian collared doves were originally native only to India, Sri Lanka and Myanmar (formerly Burma), where they typically occur in open, dry areas often associated with farming. Now they are found over much of Europe and Asia, having expanded east to China and west to Portugal. We know quite a bit about the pattern of colonization of the species in Eurasia.
In the 1600s, these birds expanded into Turkey and the Balkans. We do not know if the birds naturally dispersed westward or if they were introduced by humans. They continued to spread westward in Europe, reaching Yugoslavia by 1912, Hungary by 1930, Germany by 1945, Norway by 1954, Britain by 1955 and Portugal by 1974.
The expansion of Eurasian collared doves into Europe has been described as explosive. As long as birds have access to food from feeders or from gleaned seeds from pastures and grain fields, they can tolerate fairly cold weather. But areas where the annual average low temperature is below 32 degrees are too harsh for these birds.
These doves occur now in the Western Hemisphere as well, although in a patchwork pattern. The introduction into our hemisphere can be traced back to two events. In the mid-1970s a breeder brought Eurasian collared doves to New Providence, Bahamas. A few birds were released during a burglary and the breeder subsequently released the rest of his breeding stock of 50 birds.
A second release occurred on Guadaloupe in 1976. It is clear that the populations now established elsewhere in the Caribbean and in much of North America stemmed from these two introductions.
The first of these doves to reach North America arrived in south Florida. Confirmed records were obtained in 1986 although there were reports of collared doves of some ilk in south Florida more than a decade earlier.
By the late 1980s, Eurasian collared doves were reported from several Florida counties in the northern part of that state, Georgia and Arkansas. From that point onward, the expansion has been explosive, similar to the colonization of Europe.
Breeding populations are now established in all the Southeastern states along with California, Colorado, Illinois, Kansas, Missouri, Montana, Nebraska and Texas. Records of stragglers have been reported as far north as Montana, North Dakota and Saskatchewan. The Maine bird falls into this category.
As with the European invaders, North American Eurasian collared doves are strongly associated with humans. Suburban gardens, town parks and areas with mixed shrubs and trees provide favored habitat. They tend to avoid urban centers and woodlands. Coastal areas, particularly with mixed habitats of scrubland, pastures and grain fields, host the largest populations. These doves avoid areas of intensive farming.
The patchy distribution of established populations results from a phenomenon called jump-dispersal. Collard doves will disperse long distances, establish a new breeding population and then fill in the area between. We can expect a more continuous distribution of these birds as jump-dispersal continues. The cold temperatures in Maine may keep the species from becoming an established member of our avifauna. We'll have to wait and see.
Herb Wilson teaches ornithology and other biology courses at Colby College and perches in South China. He welcomes reader comments and questions at: