They are not afraid. It is easy to see them and even more so to hear them in any neighborhood of Barcelona, ??where they move freely. They are not afraid of people. The Argentine parrots confidently descend from the trees and without much difficulty obtain the abundant food they find on the ground. Much faster and more determined than other birds, these parrots with bright green feathers and gray chests are, along with the Kramer’s parrot (larger), the two most numerous exotic species in the city and those that, despite the management objectives environmental, more grow while the population of native birds decreases.

The latest Bird Monitoring Report in Barcelona concludes that the loss of the population of native species is constant and sustained, with a decrease of 35% between 2005 and 2022. The opposite occurs with exotic or feral species, which They register a constant and sustained growth that the authors of the report place at 40% on average during the same period.

“Currently the situation is worrying, active and decisive control measures are needed, especially with parrots, but it is a controversial and difficult issue,” says Marc Antoni from the Catalan Institute of Ornithology, author, together with Xavier Ferrer (Universitat de Barcelona ), from the report commissioned by the City Council.

On a shorter scale and comparing the data from the latest study (collected during 2022) with the results of the previous one, from 2021, “the population decline is notably greater in native spices, reaching almost 5%, while in the case For exotic birds, the reduction is almost 4%,” explains Marc Antoni.

To prepare the report, eleven itineraries have been defined throughout the city. In total, 33 kilometers that cover everything from streets and avenues, such as Paseo de Sant Joan or Diagonal, to representative sectors of the two large green areas (Montjuïc and Collserola) or smaller parks, such as Ciutadella. A team of volunteers carried out four surveys to count the birds. Since 2005, up to 15 different exotic species have been detected on these itineraries, of which eleven belong to the parrot and parakeet family. Of these, five can be considered fully established and two that reproduce the most and cause concern: the Argentine parrot and the Kramer parrot, which registers a general increase both in Barcelona and in the rest of Catalonia.

In the group of exotic or feral species, the study incorporates the pigeon, because the problems it generates, at the level of public health and biodiversity conservation, are very similar.

The rock pigeon, probably the most abundant species in Barcelona, ??recorded a significant decrease in the population between 2005 and 2015 and a clear recovery between 2015 and 2022. The change is attributed to municipal management measures to control the population. In the first period, the action was based on specific reductions and citizen awareness campaigns to avoid throwing food at them, and in the second period, the application of nicarbazine as a contraceptive agent was prioritized, a measure that did not obtain the expected results. Currently, it is estimated that just over 103,000 pigeons live in Barcelona, ??which translates into about a thousand per km2, when the tolerable number is between 300 and 400 per km2.

“If citizens stopped throwing away food, in about two years we would reach the correct carrying capacity… Reducing food resources is the key,” maintains Carmen Maté, director of the City Council’s Animal Dres Service. “Giving food to birds is a way of mistreating them, the more they eat, the more eggs they lay… and we are already seeing obesity and female birds with osteoporosis,” adds Maté. Her department has located more than 300 large feeders in the city, “some of them throw away ten kilos of animal food a day.” The objective is to eliminate these sources of food and, in parallel, the City Council is preparing a large awareness campaign that is planned to be launched in November and that could be accompanied by sanctions for those who continue to feed the animals.

Maté maintains that the problem of pigeon overpopulation must be addressed from a global perspective for measures to be effective. Two years ago, Barcelona City Council promoted the Strategic Plan for the Control of Invasive Species managed by the Generalitat but which, in practice, has made very little progress.

The overpopulation of parrots and pigeons has an impact on native species, especially those that eat from the ground, such as the goldfinch, the greenfinch, the greenfinch, the finch, the sparrow (whose population has decreased by around 60% between 2005 and 2022 ) or the blackbird (the first three, species considered threatened in Catalonia). In addition to competition with exotic species, other problems have been detected such as the presence of more and more loose dogs or more cats in parks.