Barn owls are being offered bed and breakfast at a Sussex sewage works in return for a few hours' pest control a day.

Southern Water has installed nest boxes at its wastewater works in Gossards Green, near Burgess Hill, in the hope the vulnerable birds will set up home.

The number of barn owls in the UK has rapidly declined in the last 60 years, from about 12,000 to 4,000, due to changes in their habitat.

The nests will provide ideal homes for both barn owls and kestrels.

However, there is no such thing as a free ride and Southern Water hopes the birds will help control rodent populations on the site, including rats, which are otherwise managed with poisonous bait.

The owl project was the brainchild of the firm's environment manager Mike Barker.

He said: "I heard a talk at the Sussex Ornithologist Society which described how two thirds of the country's owls had disappeared.

"I thought of all the land we have at our sites around the country and how they would make ideal spots for the birds.

"We had £100 left in last year's budget so I went to the boss with my idea, thinking he would laugh but he said yes.

"It is a perfect situation. The birds are nice to have around and they need rodents to live off.

"The call-out charge for pest controllers is £60, so we will be saving money too.

"The boxes only cost £35 and will last ten to 15 years."

Mr Barker said the response from employees had been overwhelming.

He said: "I sent round an email asking for sites willing to have the boxes and was inundated with replies."

Dr Barrie Watson, president of the Sussex Ornithologist Society, helped to assess the suitability of the site.

He will be putting ring tags on the legs of any birds which take up the nests to monitor them.

He said: "I would love to see more businesses with spare land take on box projects like this."

Jason Bowley, of the Sussex Falconry Centre, brought along Holly the barn owl to try out one of the boxes.

He said: "I think the project is tremendous."