British Trust for Ornithology survey reveals regional success story

East Anglian Daily Times: Peregrine falcons are increasingly being seen in urban settings. Picture: KATIE NETHERCOAT/BRITISH TRUST FOR ORNITHOLOGYPeregrine falcons are increasingly being seen in urban settings. Picture: KATIE NETHERCOAT/BRITISH TRUST FOR ORNITHOLOGY (Image: KATIE NETHERCOAT/British Trust for Ornithology)

The world’s fastest bird is making a quickfire comeback after years of suffering heavy persecution and poisoning to reclaim the skies over parts of Britain - with East Anglia at the forefront of the recovery.

Most of the region’s largest towns and cities are now home to pairs of peregrine falcons, with the urban areas’ prominent high buildings such as apartment blocks and cathedrals replicating the impressive bird of prey’s more traditional cliff and rocky crag nest sites. But there is a different story in upland Britain, where factors such as illegal persecution are hitting the species’ polulation levels.

In a scientific paper just published in the Thetford-based British Trust for Ornithology’s (BTO) journal Bird Study, the peregrine’s UK breeding population is said to have hit a historic high, with “particularly large” increases in England - the largest of which has taken place in East Anglia.

Scientists analysed the results from a 2014 peregrine survey to produce an up-to-date population estimate for the dashing aerial hunter. They estimate the UK breeding population to be 1,769 pairs, 22% larger than found in the previous peregrine survey in 2002 - mainly due to population increases in lowland areas, particularly in England, where many peregrines are now breeding on man-made structures.

Of about 500 monitored pairs in England, just over a quarter were on buildings, pylons, or other man-made sites. The majority were in areas where a lack of suitable nesting crags would once have resulted in peregrines being scarce or absent. However, despite the success of peregrines in such newly colonised areas, they are not doing so well in all parts of the UK, the survey found.

The number of breeding peregrines estimated for England is almost twice that reported in 2002, whilst in Wales the population is stable. On the Isle of Man and in Scotland, peregrine numbers fell but there was a slight increase in Northern Ireland. Further investigation showed a range of complexities.

Within Scotland and England, trends varied between different regions. In both countries, populations in upland regions showed the greatest declines, whilst the regions that experienced the largest increases within the UK were in eastern England. In East Anglia, the peregrine population increased from no pairs to an estimated 44 pairs between the two surveys. The Channel Islands were covered in the latest survey for the first time, with an estimated total of 16 breeding pairs found.

Mark Wilson, lead author on the paper and research ecologist at BTO Scotland, said: “The UK holds a significant proportion of the European peregrine population, and the reverse in fortunes of this incredible bird since the lows of the 1960s is great news for conservation. However, peregrines remain exposed to a wide range of factors that could impact their population, particularly at a regional level. Peregrines in many upland areas are now faring more poorly than their lowland counterparts. It is thanks to the hard work of hundreds of volunteers who took part in the 2014 survey that we have a better idea of how these birds are doing and where there might still be pressures.”

Factors limiting upland peregrine populations probably vary between different regions, the BTO said. They were thought to include ongoing illegal killing and deliberate disturbance, and changes in food supply caused by decreased availability of prey in some upland areas.

Eileen Stuart, the BTO’s head of policy and advice, added: “Peregrines are spectacular birds which have been closely monitored by volunteers and organisations for decades in Scotland. It’s good to see the number of peregrines in some lowland areas increasing, but it’s disappointing to see a decline in the uplands - particularly when the UK overall picture is positive.

“In the North-West, there has been a longer term decline with changes to food supply and exposure to environmental pollutants likely still to be affecting these birds. In some other areas, illegal persecution has been an issue, which we, along with our partners in Protection Against Wildlife Crime Scotland have been working hard to combat. As part of this the Scottish Government has also set up the working group to review all aspects of grouse moor management.”

The latest survey was funded by Scottish Natural Heritage, Natural England, Countryside Council for Wales (now Natural Resources Wales) and Northern Ireland Environment Agency. The BTO was supported in organising and carrying out the survey by hundreds of volunteers, including individuals involved in long-term studies of peregrines and members of raptor study groups.

In East Anglia, popular peregrine pairs are enjoyed by many observers in urban areas such as Ipswich, Norwich, Colchester and Lowestoft. The latest official Suffolk bird report, Suffolk Birds 2016, which is compiled by the Suffolk Ornithologists’ Group and published by the Suffolk Naturalists’ Society, reveals breeding pairs in Lowestoft, Felixstowe Docks, Bury St Edmunds, and Ipswich - the latter town hosting two pairs. A pair also frequented Orford Ness and singletons were noted in the breeding season at two other sites.

The fact that peregrines are becoming a frequent sight in town centres is highlighted in the Suffolk report with a reference to an incident in Bury St Edmunds. A young bird that had been ringed in Ipswich “surprised shoppers” when it caught and ate a pigeon in front of them in The Apex shopping centre.