In the sixth in a series of articles looking at the effects of the changes in human behaviour caused by the Covid-19 restrictions on pest species populations and behaviour, we look at the feral pigeon. With the aims of reducing transmission of the Covid 19virus, governments around the globe restricted the movement of people and closed non-essential businesses to the public now as we are in a second national lockdown we will test the resilience of these birds.
The rock dove (Columba Livia) was the wild ancestor of the feral pigeon and the first bird to be domesticated, some 6,000 years ago. It may seem unlikely that the first bird we domesticated was the rock pigeon, a comparatively uncommon species of remote cliffs. But this approach did not require capture and selective breeding, merely the provision of an alternative place to nest, usually a dovecote along its inner walls with rows of ledges or clay pots.
Today’s feral pigeons are descended from birds that escaped from dovecotes or other domesticated conditions. These domesticated pigeons were bred from wild rock doves. Feral pigeons, with a global population of millions, live in urban areas on every continent except Antarctica. Wild rock pigeons, on the other hand, are now restricted to Scottish outlying islands and isolated parts of the Mediterranean, North Africa and Western Asia.
Urban Pigeons
It is no wonder that in urban settings, feral pigeons flourish. For these exiles, buildings are ideal nest sites, mimicking the windswept cliffs used by their ancestors. If you take a walk down pigeon street you will see the ease that pigeons exploit the ledges and alcoves on our built structures. They are the ultimate opportunistic rooster. Unfortunately, parapet gutters and hopper heads can be blocked by pigeon nesting materials, feathers and faeces, enabling water infiltration into the building fabric and providing the optimal environmental conditions for the growth and production of mould species. Large outbreaks of dry rot, wet rots and black mould flourish in poorly maintained and unoccupied buildings, where substantial undetected water penetration has occurred. An unavoidable result is the resulting degradation of the historic fabric, finishes and contents. This degradation is often so drastic that many of the significant historical and architectural characteristics are lost beyond repair.
Through the lockdown period pigeons have effectively been left to colonise our cities unhindered. The tiny population of peregrines in our cities have been no match for the breeding potential of feral pigeons, although they may be the success story from Covid-19. Pigeons, being opportunistic feeders, have freely moved from scavenging on human detritus to natural forage. Unlike rats that have had mixed fortunes, pigeons are able to fly to find food sources enabling them to exploit opportunities over a much greater area. The removal of human disturbance on their nesting and breeding activities has resulted in a bumper year for the pigeon population. The survival rates of squabs is also a lot higher this year. Probably again due to the lack of human activity. Many die in the first weeks of life as they learn the dangers of the world they inhabit. The main dangers being traffic and humans.
It is likely that the population will self-regulate to a new level as we return to life in a post Covid world.
