Dear Mrs Knowlson

Just 28 days in Holloway Prison for feeding the pigeons in Croydon? British judges are getting far too lenient. If it had been me, you'd have got life.

Pigeons in our cities are rats with wings and feathers. They are ugly animals, a nuisance to pedestrians and they disfigure our buildings and spread disease. Those who feed them, as you so misguidedly have done, are probably also unwittingly feeding rats who will devour the food that the pigeons don't get. Did you think of the furry vermin when, according to the reports of your trial, you kept on tending these feathered pests because you "looked at their little faces and couldn't bear not to feed them"?

And feed them you did, despite a High Court order forbidding you to distribute food anywhere in the borough and despite your neighbours being woken at 5am by the sound of hundreds of pigeons swooping on to the roof to be fed. To avoid detection, you even went out in the dead of night, but you were trailed by a council officer who saw a car park in town carpeted with bread "like snow".

Well, I hope that you've got some reading material during your enforced leisure time. I'd suggest a copy of the Institute of Environmental Health Officers' information leaflet on Columba livia var (the feral pigeon). It points out that "much of the damage caused by feral pigeons arises from their infestation of buildings. Food stored in warehouses and processing plants may be eaten or contaminated and the machinery fouled."

A high proportion of feral pigeons are known to be infected with ornithosis, a form of psittacosis. This disease can spread to humans as a result of inhaling dust contaminated by the droppings of infected birds. The symptoms resemble influenza but can include nosebleed, lethargy and depression. If undiagnosed and therefore untreated, it can cause death, although this is rare.

Then there's the salmonella and TB that they can harbour. Not to mention the allergic reactions they can cause. You've been lucky because you were spared the poetic justice of "pigeon fancier's lung".

For my part, I'd go for the institute's recommendation: "Shooting can be used effectively. It is often useful to have an air rifle available during stupefying bait treatments as stupefied birds may sit on ledges for long periods without falling off." Alternatively, those birds which are caught in traps "should be killed by cervical dislocation", as the document tactfully puts it: wring their necks, in other words.

But killing pigeons can be recreational rather than work, as the American satirist Tom Lehrer says:

"We'll murder them all amid laughter and merriment,

Except for the few we take home to experiment ...

It's not against any religion

To want to dispose of a pigeon ..."

Mrs Knowlson, the song could have been written for you on your release from Holloway:

"If Sunday you're free, why don't you come with me? ...

And maybe we'll do in a squirrel or two

While we're poisoning pigeons in the park."

TOM WILKIE