New technology means that the movements of tiny birds like goldcrests, as well as bats and butterflies, can be charted more closely than ever before as they make their awesome annual migrations.
A Motus receiver installed at Spurn Bird Observatory recently picked up Europe’s smallest bird, the goldcrest, as it flew in from the North Sea just before dawn.
The bird, which weighs just five to seven grams (about a quarter of an ounce), was fitted with an ultralight tag by a team at Wageningen University, on one of the Frisian islands off the Dutch coast on Thursday October 20.
It emits a unique digitalised radio signal which was picked up by Spurn Bird Observatory the following morning, as it headed inland.
The timings show it crossed the North Sea in less than eight hours, flying at an average 27mph, with the help of a south-easterly wind.
Nick Whitehouse, Spurn Bird Observatory committee member, said: “We have several good examples of birds that have been tagged on the continent and are now flying close enough to the receiver to pick them up.
“This technology gives you the exact timings and directions of flights.
“It gives you much more detail about the journey.
“Once we get that ping and the data downloads automatically, it is stored on a central database and that information goes back to the tagging team.
“It was nice to know the technology was working and we got a hit from such a small bird.”
The network of receiver stations is expanding – fellow bird observatories at Gibraltar Point in Lincolnshire, Portland in Dorset and Alderney in the Channel Islands are installing Motus receivers soon.
But while anyone can host a receiver the fitting of the tiny nanotags is strictly controlled by the British Trust for Ornithology and can only be done by specialists with experience in bird ringing.
“We are trying to encourage universities and other natural history organisations to host a receiver,” added Mr Whitehouse.
“The more receivers we host the denser the system becomes and the more effective it becomes.”
