They are not scared of human presence, nor are they bothered by noise or car fumes. Species such as the magpie, the Turkish turtle dove, the wood pigeon and the Argentine parrot have become accustomed to life in the city without any problem and, given their growth, it seems that they prefer it to the countryside. While these birds flourish, others as traditional and well-known as sparrows or swifts are in recession, and tenants as common in cities as the rock pigeon - the wild ancestor of the domestic pigeon, from which it is already difficult to distinguish due to to hybridization - they have to share a menu with the increasingly abundant neighbors.
In the eighties it was almost impossible to observe a wood pigeon in Madrid, in the nineties it began to be seen, and now there are many, there are 20,000 specimens breeding within the municipality, indicates Juan Carlos del Moral, coordinator of Citizen Science of the ornithology NGO SEO / BirdLife.
The Turkish turtle dove has followed a similar process and since 1996 the population has multiplied by 10 in Spain.
It is practically in all urban centers, although it is still more like a town than a city.
As some species grow and others dwindle, the balance of birds in the city is positive, but that apparent good general condition "may mask the decline of some populations," warns del Moral.
More information
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The increasingly green cities, the scarcity of predators and the abundance of food - favored by people who feed them - and water in ornamental fountains are factors that contribute to attracting opportunistic species such as the magpie. Del Moral considers that this colonization has “part of good when it is natural as it happens with magpies, wood pigeons or Turkish turtle doves and part of bad, when it is introduced artificially like the parrots that we have brought from another continent. and then we released ”.
The problems occur because "the city lacks trophic levels for there to be natural control of the population, there are no predators and, if they have food, some species grow more and more without any limiting factor", contributes Joan Carles Senar , Head of Research at the Museum of Natural Sciences of Barcelona.
So are these tenants with whom you share sidewalks and parks.
The clever black and white magpie
Magpie perched in a tree.SEO / BirdLife
They are increasingly easy to see prowling around houses, jumping from tree to tree or roof to roof. In the latest report published by SEO / Birdlife this month, drawn from the observations of thousands of volunteers, the magpie (
Pica pica
) shows a moderate decline. A global fact in which it is not noticed that in the city this bird has found an ideal ecological niche to establish itself. “The corvids [group to which the black-and-white magpie belongs] are very intelligent and the magpie does not have great problems adapting to the city where predators are scarce, leaving behind the rural areas to which it has always been linked, perhaps due to abandonment of the field and by the use of pesticides ”, explains Del Moral.
Senar assures that, in the city, this species constitutes a problem because it preys on nests.
"They eat everything and are dedicated to looking tree by tree looking for eggs and the chickens of small birds such as blackbirds, verdigris or goldfinches," adds the scientist.
As an example of what is happening, the scientist puts the case of the Botanical Garden of Barcelona, where the increase in the population of magpies has resulted in the decline of other birds.
The wood pigeon: from forests and crops to asphalt
A pair of wood pigeons.
SEO / BirdLife
With its characteristic spot on both sides of the neck and on the wing, the wood pigeon (
Columba palumbus
) was until a few decades ago a typical species of forests and crops in Spain, but now it is common in cities.
"The reason is not very well known, perhaps because cities are increasingly green and they need trees to reproduce," says del Moral.
Although they breed in the city, they usually feed in the field.
In Madrid they began to be seen in the nineties and now 20,000 specimens nest within the municipality, from where they leave in flocks in search of barley, wheat or acorns along routes that pass through the airport, Casa de Campo or Moncloa.
In Barcelona, the first breeding date dates from 1996, and currently nests in most of the districts.
The Turkish turtle dove, native to Asia
Tortola_turca © Marcin Perkowski-shutterstock_
The Turkish dove (
Streptopelia decaocto)
is slender and easy to distinguish by its light tones and the black patch that covers the back half of the neck.
Originally from South Asia, it has been colonizing territories and can now be found throughout Europe.
It has gone from an original habitat of savannas and cultivated spaces to the parks of dense urban centers.
Since it reached the Peninsula in the early 1970s, in just three decades it has occupied the entire peninsula, the Balearic Islands and the Canary Islands, where it has become a common species in rural environments.
The population in Spain has multiplied by 10 since 1996. In Catalonia the species was detected for the first time in 1968, but it was not until the seventies and eighties of the last century that the first stable reproductive populations were established.
The first breeding date in Barcelona is from 1989 and since then its rise has continued and it is already in all the districts of the city.
Wild or domestic pigeon, the same as always
Wild pigeons on a roof.
It is the most common and urban pigeon of those that live in Spain and due to the hybridization with the domestic ones they are difficult to distinguish. The color of their plumage is usually bluish gray and can be differentiated by the black bands that can be seen on their wings when they are perched. The
rock
pigeon (
Columba livia) is
native to Europe and is associated with rocky cuttings, which are exchanged in cities for old buildings. In large cities it can be found anywhere and its density depends on the number of inhabitants (especially older people who live alone who provide them with food) and the old buildings where they find breeding places, explains the Atlas of Biodiversity of Barcelona.
Their density can increase rapidly because they are fertile from six months of age and capable of carrying out numerous clutches per year from March to October.
They nest in cavities, air chambers under roofs, terraces of unused floors, abandoned buildings ... sometimes becoming a nightmare for neighbors and municipalities.
The Argentine parrot, the one that came from South America
Argentine parrot in a tree.
SEO / BirdLifeJuan Bécares
The Argentine parrot is another song, it did not come naturally but as a pet from South America. From 1986 to 2005, when the importation of wild birds was prohibited in the European Union, at least 190,000 individuals of Argentine parrot and about 63,000 specimens of Kramer's parrot legally entered Spain, according to a study published by scientists from the Malaga University. From this germ and from the specimens that were released intentionally or accidentally, the 20,000 wild specimens of Argentine parrot and 3,000 of Kramer were born, which SEO / BirdLife recorded in a 2015 census. Thus, it has become common in cities, becoming a threat to biodiversity (they expel native species such as sparrows), and a headache for local authorities.With its intense green tone and its strident cries, the species does not go unnoticed by the population, who feed them, despite being prohibited.
The Madrid City Council launched last week the plan announced in October 2019 to hunt and slaughter most of the 13,000 specimens that fly through the city. The eggs will also be sterilized to reduce their reproductive rate. The Atlas of the Birds of Europe estimates that 24,000 birds live in Europe and that the population doubles in Spain every three years, in Italy every three and a half in Greece every 1.7. The survival rate is the same as in their native areas of South America, but the reproduction in Europe is much higher, they breed twice as much as there and 55% of the birds with one year do so as well, something that does not happen in their countries either. originally.
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