Plea over Suffolk and Essex herons and egrets
PUBLISHED: 07:30 17 March 2018
British Trust for Ornithology representatives appeal for nest-site information
How many herons nest in Suffolk and Essex? Frankly, conservationists just don’t know.
Ol’Frank, as the grey heron is sometimes colloquially referred to, may be one of Britain’s best known and most instantly recognisable birds, but it is almost certainly under-recorded as a breeding species and its true population is something of a grey area.
The Thetford-based British Trust for Ornithology (BTO) aims to discover the species’ precise nesting numbers - along with those of the grey heron’s smaller cousin the little egret - in a special national survey this spring, and an appeal has been made for potential Suffolk and Essex nesting locations to be reported by members of the public.
The plea has gone out from BTO representatives Mick Wright, who covers Suffolk, and Rod Bleach, his counterpart in north-east Essex.
“Ever since 1928 a heronry census has been carried out in the UK - the longest-running single species census in the world,” they said. “This year being the 90th anniversary of the census a big effort is being made to discover and record all grey heron nest sites in the UK.”
In recent years it was estimated that there were about 10,500 grey heron nests in the UK, but numbers were subject to fluctuations. Little egrets began to breed in Britain in 1996 and their current population was thought to be more than 1,000 pairs.
Mr Wright feared that in Suffolk the grey heron was in decline but it might be that some heronries had not been recorded in recent years. He would be checking 15 such sites in this spring’s study, but, he added: “With this 90th anniversary census we are making a concerted effort to find out the true numbers and the public can be a great help by letting us know of any potential nest sites they may know of.”
There were several possible reasons for the perceived decline in heron numbers, said Mr Wright. Grey herons returned to their heronries early in the year, with egg-laying in March, so they could be susceptible to severe weather. Disturbance of heronries could also be a cause, he said, as footpaths led through many woodlands where herons nested and “footfall these days is far higher than it has ever been before.”
Woodland management could also be a factor, he said. “I have known Bridge Wood, Ipswich, for a long time, for example, and many years ago it had a thriving heronry of up to 40 nests. Then it was clear-felled and planted up with many conifers and now the heronry has gone,” he said.
Little egrets were now widespread in Suffolk, with three-figure counts being far from unusual. The species, which often nests alongside grey herons in woodlands, had “burst onto the Suffolk scene” in the early days of its UK colonisation, with five known colonies in the county. “Now though the population seems to have levelled out and it has not reached the increased level I was expecting,” said Mr Wright.
“There are still only five or six known colonies and perhaps about 10 pairs - we hope the BTO’s survey will give us the true picture and if the population really has levelled out it might help us find out why.”
Mr Bleach said: “Counts have been very sketchy in recent years, but there are perhaps about 35 known grey heron nests in north-east Essex – from just three known sites. The number of little egret nests looks to be similar, but I know of one egret site that was not counted. So, are there more egret nests than heron nests in north-east Essex? That’s something we hope this year’s census may tell us.”
Members of the public were urged to report known or potential grey heron and little egret nest locations to Mr Wright and Mr Bleach. Volunteers were also needed to visit old recorded sites to establish if they are still occupied.
Mr Bleach can be contacted at firstname.lastname@example.org
Mr Wright can be contacted at email@example.com