A FORMER policeman has admitted stealing nearly 650 wild bird eggs, including more than 60 from some of the rarest species in the UK.

Michael Upson amassed the collection – which included eggs from the wood lark, Cetti's warbler and marsh harrier – over a 10-year period while working for Suffolk Constabulary.

According to the RSPB, notebooks recovered from his loft revealed that he took kittiwake eggs from Lowestoft pier while working as an active sergeant on night-shifts in the town.

Norwich Magistrates' Court was told on Wednesday that Upson developed a sophisticated indexing system, detailing how and when he found each egg, which was discovered by police – along with egg-blowing drills – when they searched his home in Sotherton, near Halesworth, in June.

Upson, a father of two, will be sentenced today after pleading guilty to two charges of possession of eggs.

The court was told the 52-year-old amateur ornithologist would have had a 'significant impact on the species' and the environment in the Dunwich and Westleton area, where he found many of the eggs.

Outside court, Mark Thomas, senior investigator for the RSPB, called the case 'shocking' and said that Upson had also travelled the UK to 'systematically target some of the country's rarest birds'.

'Norfolk and Suffolk are hotspots for wild birds and the police and the RSPB and other organisations work together to protect these birds.

'He was in a position of authority and trust and he broke that – he broke it for over 10 years,' said Mr Thomas.

The 53 wood lark eggs Upson had in his collection were taken at a time when there would have been only 500 to 700 pairs in the UK, he said.

'They are extremely well camouflaged on the ground, and it would have taken hundreds of hours to find these nests,' he added.

Prosecutor Judith Piggin told the court that officers found the eggs hidden in suitcases which had been 'secreted' in towels in an airing cupboard, when they executed a warrant on June 21.

The officer, who has since retired, made full admissions to police but said the collection had been made between 1991 and 2001, and he had not looked at them for many years.

A total of 649 wild bird eggs were found stored in margarine tubs, including 65 particularly rare eggs, defined as Schedule 1.

A log book detailing the circumstances of each egg find was found stored in a water tank by police. Roger Thomson, mitigating, said the collecting had been the result of 'a mad period' in the 1990s for Upson, during which he had been having marital troubles and suffering from depression, but that he knew his actions were wrong.

He denied that his client, a 'keen naturalist and ornithologist', had ever taken eggs while on police duty.

Mr Thomson said: 'The collection has been gathering dust in the attic. It's been up there and he has not shown it to anyone else.

'He wishes now that he had just thrown it away but he found it difficult. He knew it was wrong to have them in the first place and thought it would be more wrong to have thrown them away.'

Magistrates will also rule today whether Upson's diaries, maps and more recent photographs can be returned to him.

? The RSPB says detailed notebooks found at Upson's house document his egg collecting trips with associates around the UK.

They include visits to the Western Isles to steal golden eagle eggs; south Devon to take Cetti's warbler eggs; north Wales to steal chough eggs; and the New Forest to take hawfinch eggs.

In one notebook, Upson writes about taking kittiwake eggs from Lowestoft Pier while on duty as an acting sergeant on three different police night-shifts – though his lawyer denied he had ever taken eggs while on duty.

The egg collection was found in an old suitcase with hundreds of egg data cards which Upson faked to suggest the collection pre-dated the law. But notebooks found in a water tank in the loft revealed where he found the eggs. Mark Thomas, the RSPB investigations officer leading the case, said: 'Evidence from the diaries indicates that Upson stole over 900 wild bird eggs in an eight-year period. Not all of these eggs were recovered.'

See the Lowestoft Journal website later today for a report on Upson's sentencing