Thermal Imaging Camera
A preliminary report from Chew Valley Ringing Station
We found the YouTube videos from the West Midlands Ringing Group about using a Thermal Imaging Camera to be quite inspiring. The technique used is an enhanced form of dazzling or netting with the imager helping to locate the birds. Mainly they were catching Skylark, Snipe and Woodcock, birds that we rarely encounter. We began fund-raising and were delighted, of course, when we received a grant from the BOC to purchase one.
It arrived in early summers, just in time to try it out on the larger nest boxes to see if they were occupied. This worked quite well providing the box was examined before the sun had a chance to warm it up. Then it was a matter of waiting until the autumn/winter for the evenings to draw in.
Many years ago (1980s) I helped the Priston Ringing Group with a Skylark ageing project. The problem with Skylarks is that they are like House Sparrow and Long-Tailed Tit in which both juveniles and adults have complete moults in late summer. From autumn onwards, therefore, the first-year birds cannot be aged separately from the adults. However, although Starlings also fall into this category with both age classes having full moults, the new first-year birds’ plumage is subtly different from the adults. We wondered if this might be true for Skylarks but, of course, needed to have known aged birds to look for any plumage differences. We ringed somewhere around 700 birds and would regularly catch between 10 and 30 birds per night in the Marksbury / Priston area. Unfortunately by the time several years had elapsed, and we were retrapping known 2year plus, we still could not detect any plumage differences so the project came to an end.
There seem many fewer Skylarks in the Marksbury/Priston area now. The picture, taken with the Thermal Imager, shows a few that were spotted in a field near Paulton. Catching was unsuccessful but we did get an invite to an organic farm in Wiltshire.
Skylarks near Paulton |
The field used, now ploughed up, but similar to the one in the picture was moderately successful. The birds roosted in the furrows and the best way to locate them was by walking at a right angle to the lines of stubble. We used a 2m x 20m net held horizontally and the person with the camera would direct the ring
ers so that the net could be dropped over the bird(s).
This journey across the county border yielded 18 Skylarks |
Using the camera at night we spotted birds such as Red-legged Partridge, Pheasant, Snipe and Woodcock and mammals; Badger, Roe Deer, Muntjac, mice, rats, Foxes and even a probable poacher!
Skylark using Thermal Imaging Camera |
by Mike Bailey