Drone photography has captured an amazing bird’s-eye view of the heronry at National Trust Belton House in Lincolnshire, as part of the British Trust for Ornithology’s (BTO) annual census.
Used for the first time and flying 15 metres above the treetops (30 metres above the ground), while adhering to strict guidelines for wildlife monitoring, the drone enabled the team to get a much better picture of how many nests are in Belton’s heronry with minimal disturbance to the birds themselves.
Ecologist Andrew Chick, who conducted the survey, expected to find a couple of active nests but was astonished to discover 11, indicating 22 breeding birds are happily incubating three to four eggs in each.
“This statuesque bird is often spotted alongside rivers across the country, where it waits patiently to capture its prey – mainly fish, amphibians, small mammals, insects, and eels,” said Andrew. “They can live up to 20 years, growing to around 1 metre high, with an impressive wingspan of 1.85 meters and can weigh up to 1.5kg. They usually lay their first egg in mid-March, so quite early, and only have one brood per year.
“These herons have probably chosen to nest in this particular Scots Pine tree because of its easy access to Belton’s ornamental ponds and rivers, which the National Trust has been actively managing and improving. It’s likely the herons have been present at Belton for decades, but thanks to the view from above this year we’ve been able to get a much more accurate record of how many are nesting in the heronry.”
Carl Hawke, Nature Conservation Adviser at the National Trust says:
“It’s great news to discover our heronry at Belton is much larger than previously thought. We have been working in partnership with Environment Agency and others to restore the stretch of the River Witham that runs through the Belton estate. This has included restoring the natural features that were missing, for example increasing the speed of the flow of the river in some places, putting in gravel to create shallow areas and creating riffles – spawning areas, to attract species like white clawed crayfish and wild brown trout. Later this year we plan to recreate wetland habitat alongside the river that will benefit the herons further.”
The number of grey herons in the UK has been steadily growing in recent years, however in Lincolnshire there has been an unexpected decline. In 2021, only 20 breeding sites for grey heron were recorded in the county, so the 11 nests at Belton are well over the average number recorded. While the full 2022 count for Lincolnshire has not yet been compiled, the team hopes the discovery at Belton shows that heron numbers in the county are improving. Carl says:
“We’re not really sure why numbers had previously dropped here.
“It could be down to a number of factors such as competition for nesting sites with other birds, or possibly the effects of intensive farming on waterways, it’s difficult to know for sure. But it’s clear that the conservation work we have done here at Belton is having a positive effect on the breeding population which is fantastic.”
The simple aim of the annual Heronries Census is to collect counts of ‘apparently occupied nests’ of herons (as well as egrets and other waterbirds) from as many heronries as possible in the UK each year. Last year’s census collected data from 796 sites and close to 9,500 grey heron nests were recorded.
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