Europeans have called many things, besides pirates, after the Berber people of North Africa. There were Barbary wars in the early 19th Century. The “prickly pear”, a cultivated cactus, is known as the “Barbary fig”. The Barbary stag of the Atlas Mountains, Africa’s only deer species, has survived but the Barbary lion was hunted to extinction. Europe’s sole wild primate, the Barbary ape of Rock of Gibraltar fame, is actually a macaque.
On a visit to Tenerife, last month, I encountered another member of the Barbary club. Among the collared doves, cooing loudly in towns and the countryside, there were miniature ones, more elegant and tamer than their peers. These exotic little pigeons, I discovered, are known as Barbary doves. The blue tit of Tenerife is more colourful and a finer singer than our Irish one, but it’s not a distinct species. Is the Barbary dove, likewise, just a local variant of the Eurasian, or some other, collared dove?
The collared dove has such an unusual history that almost anything is possible. Like the brown rat, and the black one before it, this creamy pinkish pigeon, with a dark collar around the back and sides of the neck, is one of the world’s great colonisers.
A century ago, collared doves were sedentary Asian residents, found from Turkey through India to China. There was no hint of the foreign adventures to come. Then, in the early 20th century, they began to expand their frontiers westwards. The Balkans were colonised in the 1920s. Having reached Hungary in 1932, they invaded what is now the Czech Republic four years later. After the Second World War, collared doves moved into Germany. The assault on Britain began in 1955. A pair nested in Dublin’s Glasnevin Cemetery in 1959 and another set up home in Galway city that year.
The new arrivals prospered in Ireland, as elsewhere, in both urban and rural locations. Soon, numbers were increasing by 100% annually. Twenty years later, the expansion had slowed to about half this rate. The Common Bird Census recorded an increase of about 44% between 1998 and 2010. This resourceful bird has continues to thrive here; according to the Bird Atlas, published in 2013, its range has expanded by 52% in Ireland since 1990, compared to only 8% in Britain.
The story has been similar elsewhere. In 1986, collared doves were nesting in the north-western tip of the Iberian Peninsula. By 1999, they had crossed the Straits of Gibraltar, occupied Morocco, and colonised the Canary Islands, including Tenerife.
The European collared dove has a close relative living south of the Sahara; the African collared dove is a distinct species. The little Barbary dove, described by Linnaeus in 1756, is thought to be a domesticated version of it. Barbary doves, it seems, were brought as pets to Tenerife, probably by European settlers. In due course, some of them escaped. Cosseted and pampered, cage birds seldom survive for long in the wild, but the Barbary fugitives were made of sterner stuff. Their African ancestors frequented semi-desert habitats provided they had access to water.
The island of Tenerife was formed by repeated volcanic eruptions and much of its terrain is desert-like. Water is a scarce commodity but reservoirs created to store it are dotted throughout the landscape. The habitat, together with food handouts from their former owners, has suited the Barbary dove.
The bird, therefore, was well established on Tenerife long before its blow-in cousin arrived from Europe a few decades ago. Captive European and African collared doves readily interbreed, producing hybrid young. Hopefully, mixed marriages between the Europeans and their distant cousins won’t become the norm. Otherwise, the little Barbary dove of Tenerife will cease to exist as a unique form.