Knots at the RSPB’s Snettisham nature reserve will be one of the subjects featuring in the
BBC’s Winterwatch wildlife programmes in January, after a film crew spent two long nights
recording the birds’ nocturnal behaviour on the mudflats of The Wash this month.
The crew used low light, thermal imaging cameras, capture ground-breaking footage of the
night-time habits of the tens to hundreds of thousands of these wading birds, which spend
the winter here.
A spokesman for the RSPB said: “This is the first time that thermal imaging technology of the kind used by the BBC crew has been used to observe the nocturnal behaviour of these birds.
“Its use in this case will help to shed light on an aspect of these birds’ lives that was previously a mystery and answer an interesting scientific question about the how the decreased threat of predation at night may or may not affect their behaviour.
“As far as scientists know, peregrines don’t hunt at night in the Wash. The Winterwatch team were tasked with finding out whether the knot would be pushed off the mudflats by the tide and fly into the gravel pits in the same numbers as they do during daylight, or if they would be more likely to separate into smaller groups.”
These short legged, dumpy wading birds favour estuaries and other intertidal habitats, which provide a rich source of food. Large numbers of knot colonise the Snettisham mudflats over the winter months where they feed mainly on small shellfish, only taking to the air if spooked by marauding peregrines.
At high tide the knot can be observed congregating on the water in large dense flocks. This flocking behaviour helps reduce the odds of a single knot falling prey to their avian predators. During the highest tides, the knot are pushed inland away from the mudflats and fly into the nearby gravel pits. As far as scientists know, peregrines don’t hunt at night in the Wash. The Winterwatch team were tasked with finding out whether the knot would be pushed off the mudflats by the tide and fly into the gravel pits in the same numbers as they do during daylight, or if they would be more likely to separate into smaller groups.
Knot undertake one of the longest migrations in the birding world. Tens of thousands of knot leave their breeding grounds in the Canadian Arctic and Greenland to overwinter on the coastlines and estuaries of the UK. However, rising sea levels due to climate change, and threats to estuarine feeding grounds, such as port developments or artificial estuarine barriers, could have dramatic impacts on migrating populations.
As a Special Area of Conservation (SAC), the Wash’s intertidal habitats and the vast amount of wildlife they support are afforded a high level of protection under Europe’s Birds and Habitats Directives, ensuring the preservation of one of Europe’s most important places for migrating waders. RSPB’s Snettisham nature reserve plays host to thousands of these engaging and quirky birds each year.
Jim Scott, Sites Manager for RSPB North West Norfolk Reserves, said: “I really enjoyed working with the crew from Winterwatch and it was fascinating to see the results of the filming.”
If you would like to see those results for yourself and find out what the team discovered about the Knots’ nocturnal activity, tune into Winterwatch on the BBC between Monday 19th and Thursday 22nd January. To see these amazing birds in action in the flesh this winter, head over to RSPB Snettisham nature reserve, which is open throughout the festive season. To find out more about visitor facilities at the nature reserve, visit www.rspb.org.uk/snettisham.