Monday, July 20, 2009

Why is culling ineffective?

https://secure.wsa.u-net.com/www.animalaid.org.uk/campaign/wildlife/pigeons.htm

Why is culling ineffective?

In areas where culling is carried out, there will be an initial reduction in pigeon numbers. However, this effect is very short term as the population will almost certainly have returned to or even exceeded the previous level within a few weeks. This is because pigeons control their own numbers according to the food source available.

Approximately 90% of pigeons die in their first year and the main cause of death is starvation. The mortality rate of adult pigeons is very low, typically around 11% (2). Therefore when culling is carried out on a pigeon population, the vacancies left by the dead birds are quickly filled by young birds.

This means that killing adult pigeons in a flock discriminates in favour of young birds who would otherwise have perished. It has no long-term effect on the level of population, as it merely rejuvenates the flock.

A culling programme was carried out in Basel, Switzerland; a city which had a population of approximately 20,000 pigeons. From 1961-85, 100,000 pigeons were culled by shooting and trapping. Despite this, the population remained stable.

In 1988 a group called Pigeon Action was founded to establish an ecological and long term solution to the city's pigeon issue. They began a programme of public education campaigns which warned against feeding pigeons and installed pigeon lofts from which eggs were removed. As a result, the population was halved within four years.