A pigeon cull is about to get underway as North Walsham launches its deadliest weapon to date against the town's most unwanted residents, dubbed health hazards and nuisances.

Traps are due to be set at strategic points around the town centre and caught birds will be killed.

The move follows years of attempts to reduce the number of pigeons in Market Place where they roost in disused shops, gather on ledges and foul large areas of pavement with droppings and feathers – but people are still feeding them.

In October 2008 town councillors arranged for a Harris hawk to fly through the town centre early one morning in a bid to scare away the pigeons. But they could not afford the estimated �20,000 cost of repeating the experiment twice a week for a year.

Environmental health staff from North Norfolk District Council (NNDC) will carry out the cull, which is due to begin later this month, with the backing of North Walsham Town Council.

James Wilson, NNDC's environmental protection team leader, said: 'The traps will be checked two or three times a day and the pigeons will be humanely destroyed in accordance with current best practice methods and all applicable legal requirements.'

He estimated that the pigeon population was in the hundreds and said the aim was to reduce numbers within the built area of Market Place where most of the problems were caused. Birds roosting in the ruined church tower will not be targeted. A cull carried out in the 1990s in Cromer was deemed a success, Mr Wilson added.

NNDC is writing to all Market Place businesses telling them about control measures taken to date and asking those who have not already proofed their buildings against pigeons to do so, using spikes or netting.

Particular hot-spots are:

* Coral's bookmaker's: Mr Wilson said the pigeons were 'enjoying' hanging on to netting put there to discourage them

* 4 Market Street: the owners had tried to pigeon-proof the demolished building but the weather had destroyed their work. They would try again

* former Market Place fishmongers: it had been closed at the rear but the pigeons had found their way in. It has now been closed again

* Broadland Travel and Break charity shop: promises to proof both buildings had not yet been carried out. The ledge above the Break shop is now one of the worst for pigeons in the town

Mr Wilson said pigeons carried many diseases and their acidic droppings reacted with chemicals in stonework causing erosion. A build-up of droppings could also become infested with mites and insects which could then enter homes and stored products. Pigeons blocked gutters, downpipes and chimneys, which could cause water damage to properties, or lead to gasses such as deadly carbon monoxise being forced back inside a home.

He added: 'Large numbers of roosting pigeons also give rise to odour and noise complaints, not to mention the risk to health and safety in terms of slipping hazards on pavements and fire escapes from accumulations of droppings.'

Mr Wilson is also going to investigate possible sites for posting notices asking the public not to feed pigeons after reports of crumbs being deliberately scattered around the Market Cross and suet balls left on ledges outside Market Place flats, discovered when members of the Christmas lights team were on ladders putting up displays.

Eric Seward, NNDC's cabinet portfolio holder for the environment and a North Walsham town councillor, said the cull was only one of a number of preventative measures aimed at controlling the problem, but none of them would make it disappear.

* Pavements in Market Place, Market Street and Church Street are due to be steam-cleaned this Sunday as part of North Walsham Town Council's efforts to spruce up the town.

And volunteers are needed to help with the town's annual spring clean, on April 15, from 10am to 12.30pm, meeting at the town hall on New Road.

Plastic gloves and sacks will be provided but those taking part are invited to bring their own tools for helping clear litter and weeds from areas not cleaned by North Norfolk District Council.

Town councillors heard at their meeting last week that a writer from the Rough Guides series of travel books would be staying in North Walsham on April 18 and they hoped the steam and spring clean would help the town look its best.

The company's series includes a Rough Guide to England, a Rough Guide to Accessible Britain, plus regional titles, but a spokesman was unable to say why their writer would be in the town.