Like many major cities, Barcelona has a pigeon problem.
As the population of birds has swelled to an estimated 85,000, the waste pigeons produce in public spaces has become an increasing burden. To curb the number of birds, and pigeon droppings, the city had been mulling over a plan to collect and kill hundreds of the birds. But after push back from animal rights groups, the local government decided to try a different tactic: give the pigeons birth control pills.
First, a detailed census of the pigeon population will take place to determine the size of the population, according to El Mundo. Then, in the spring, the city will install 40 feeders dispensing pellets spiked with the birth control medication around the city, concentrating on areas of most complaint. One Barcelona city councillor reportedly estimated the pills could curb the population by 20 percent in the first year and up to 80 percent over time.
The pills contain nicarbazin, a drug that was originally used only to prevent coccidiosis, a parasitic infection, in chickens. But one of the side-effects of nicarbazin is that it makes female chickens infertile by weakening the walls of the yolk, allowing it to mix with the whites and preventing fertilization. In the 2000s, wildlife managers worked with drug manufacturers to repurpose nicarbazin as a birth control method for out-of-control wild bird populations.
In the US, the birdie birth control has successfully been used by the Department of Agriculture to manage feral pigeon and Canada goose populations, but these were in more rural settings. Other cities in Europe, including Genoa, have also already tried nicarbazin to deal with pigeon overpopulation, and its been done on a neighborhood-level in Los Angeles, but never on a wide scale in a major city, as we'll see in Barcelona.
It could set an example for other cities like New York, where pigeons cause perennial debate and where traditional culling methods—like simply shooting the pigeons—aren't practical. New York City recently launched a program to capture, sterilize, and release deer on Staten Island, where the population of white-tail deer has exploded, so maybe pigeons on the pill aren't far behind.
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