Park and glide pests

MANY in York will no doubt be heaving a sigh of relief today at the news that the city's notorious Crow Gang is to be reprieved. The two mischievous crows, nicknamed Russell and Sheryl, who have been causing mayhem at the Askham Bar Park & Ride by attacking car windscreen wipers are not to be culled after all, council chiefs have decided.

Instead, they will be caught and relocated to another area - hopefully, if such can be found, one that doesn't have too many cars.

This is good news indeed for anyone who appreciates a spirit of mischievous anarchy among our resident bird population. It doesn't, however, solve the underlying question: just what made these two previously harmless examples of crowhood suddenly turn into psychotic car haters?

Never let it be said the Evening Press doesn't go that extra mile in search of an explanation. The reason, says pest control expert David Hizzett of Haxby-based RM Environmental Services, probably has to do with that age-old source of conflict and confusion, sex.

It is, David points out, the crow breeding season - enough, in itself, to make any self-respecting bird a little addled. So the most likely explanation for the couple's odd behaviour is either that Russell is trying to impress his missus by bringing her the crow equivalent of a diamond necklace (ie, a piece of tatty rubber pecked from a windscreen wiper: you have to learn to think in these matters like a crow and not a human being, David says); or else it's territorial.

Crows, David says, are highly territorial birds, and will fight to protect their 'patch' from any other crows that may be hanging around. Possibly the most likely explanation for their odd behaviour, therefore, is that they are catching site of their reflection in car windscreens, and attacking them. The reason it is the wipers that are suffering is because, naturally, the birds (crows being highly intelligent members of the bird family) are going for the soft and vulnerable bits.

For birds to attack their reflection during the breeding season when the territorial instinct is at its height is not, apparently, uncommon. David says he once had a Triumph Herald with highly polished hubcaps. "And a chaffinch spent a whole fortnight trying to batter himself to death and get rid of his reflection," he says.

David Hirst of the RSPB's North of England office agrees that territoriality is the most likely explanation for the birds' behaviour - far more likely than that they have suddenly gone all Hitchcock, and developed a psychotic hatred of people and their machines.

"It may well be that they are seeing their own reflection in the windscreen," he says. "So it is quite possible that if you build a car park in the middle of a crow's territory, they feel they have been invaded, and have to defend their feeding space against all comers. If you had a burglar coming to your house, chances are you would try to scare them away too!"

If it really is territorial behaviour that is leading the birds to behave so oddly, then chances are they will soon stop being such a nuisance.

Once Sheryl lays her eggs and the breeding season comes to an end, David Hizzett points out, Russell is likely to calm down.

So the Crow gang's depredations might be quite short-lived. If they continue with their odd behaviour, however, what will be the best way to deal with them?

There are a couple of simple strategies that may help motorists to protect their windcsreens. The most effective, David Hizzett says, may simply be to cover your windscreen with a cotton sheet when you leave the car there, trapping the ends of the sheet in the door and stretching it across the entire windscreen. That will both stop the birds seeing their reflection, and make it impossible to get at your wipers.

Alternately, suggests David Hirst, simply stand your wipers up vertically away from the windscreen when you park your car: there is some evidence to suggest that stops the birds being able to get at them.

As to the birds themselves, simply relocating them as the council plans may not work, David adds. Judging by the determination with which they are defending their patch, the Askham Bar Park&Ride is clearly a prime bit of crow real estate - a crow's des res. "If you had a fabulous house in York, a top property that became empty, it wouldn't be long before someone else moved in," he points out. "In the same way, if you have a great hot-spot for crows and take the resident crows away, you will soon have some new crows moving in."

The newcomers, of course, may not share Russell and Sheryl's odd habit. But then again, they may.

How the experts deal with the feathered menace

The Crow Gang aren't York's only airborn pests. The city has long been plagued with geese - particularly in Rowntree Park - and more recently, pigeons have become such a nuisance that the city council is considering pigeon-proofing the Mansion House in a bid to stop it constantly being coated in bird droppings.

So what, according to the experts, is the best way of dealing with these menaces?

n Geese: Culling with the consent of DEFRA would be the most effective solution, says registered pest control technician Trevor Porter of Wheldrake-based Pest Wise. He knows that will not go down well with many people: but other ways probably won't work.

Bird Scarers, which let off a loud bang at regular intervals, are great for keeping birds off agricultural land, but would go down like a lead balloon in a public park.

There are silent bird-scarers, gaudily-coloured mannequins or monsters that can be set to jump up suddenly, but even they probably wouldn't be too popular.

You cannot 'bait' (lay poison) for ground-feeding birds in a public park for obvious health and safety reasons, he adds - and hiring dogs to keep the birds away would be impractical because you would need to let them loose so often.

Netting works well with some birds, suggests David Hizzett - but probably not for the Rowntree geese. You would effectively have to enclose much of Rowntree Park with a six-foot-high net to keep the birds away and allow people in - which would not be acceptable.

Pricking their eggs to reduce future population numbers may be one long-term solution: but again he thinks culling, with DEFRA's permission, would be the most obvious solution.

n Pigeons: Pigeons are known in the trade as 'flying rats', says David Hizzett cheerfully - because a single pair can produce as many as 18 young in one year. No wonder they are becoming a problem. It's not just the nuisance factor, either.

Pigeon droppings are acidic, so can damage the stonework in some of York's beautiful buildings, and they can carry disease, says Trevor Porter.

The best way of controlling pigeons, David says, is either to restrict their food supply (which means fines for anyone feeding them, a la Trafalgar Square, and improved cleaning of the city's streets) or to 'pigeon proof' buildings by using nets, blunt spikes or strategically-placed wires that stop them landing.

That, however, just shifts the problem somewhere else, he says - a bit like CCTV cameras and criminals. Another possibility is a cull - possibly by drugging the birds first and then humanely despatching them.

David believes one more pigeon-friendly scheme tried with some success on the continent may be the Denmark method.

The Danes are to set up 'feeding programmes' outside the city, so the birds learn there are richer pickings there and desert the city centre for pastures new.

And what about simply catching them and relocating them? It won't work, says David.

Pigeons have a strong homeing instinct.

"And they would be back in York faster than you!"

Updated: 11:07 Tuesday, April 06, 2004