Sunday, October 15, 2006

Pigeon Control

This Sunday's New York Times Magazine has an article on approaches to controlling feral rock pigeons and the bitter battles they generate. The article is interesting because it highlights some of the conflicting impulses that inspire and frustrate attempts at animal control, especially when it comes to birds. As we all know, feral pigeons disgust many humans by leaving large amounts of excrement on buildings, sidewalks, and cars, and by sustaining large populations. So cities and towns spend large sums to clean the fouled surfaces and invent new ways of keeping the pigeons away. Unfortunately for the towns, pigeons are not easily suppressed. Spikes and grease simply make the pigeons move from one spot to another, and many people oppose lethal control. At the same time, breeding populations of pigeons are sustained by people who feed large numbers of pigeons with bread crumbs and seed.

One group called PiCAS has proposed using dovecotes to lure pigeons to specific locations in city parks and then persuading feeders to feed birds only at those locations. Meanwhile, the eggs of the pigeons would be replaced with dummy eggs to prevent the population from growing. The claim is that such a program resulted in the halving of the pigeon population in Basel, Switzerland. As a result, this group has been trying to inspire similar dovecote programs in American and British cities. The program is advertised as a humane way to reduce the pigeon population.

As it turns out, the project PiCAS cites as evidence relied heavily on a form of psychological pressure. (Even the cited paper makes this clear.) Basel initiated a widespread campaign to make feeding pigeons socially unacceptable. Individual citizens harrassed feeders as they went about their routines, so that many pigeon feeders stopped feeding completely. In the end, the reduced availability of food is what reduced the pigeon population - not the egg control or the dovecotes.