TreeStuff

Thursday, 4 June 2015

Constant effort Site

Things were quiet at the reedbed. Normally there would be a clamour of sedge warblers singing from every corner of the reedbed. But this year it is very quiet, and the reedbed is slow to grow, meaning less cover and less insects to feed on.

For over 20 years Alan, fully licensed by British Trust for Ornithology, has carried out a special type of bird monitoring called a Constant Effort Site. This involves arriving at the ringing site at dawn and setting up special nets in specific places to capture and record the biometrics of many species of migratory and resident birds. Each bird is given a tiny metal BTO ring on one leg with a unique reference number. We also take wing length measurements, weigh them and each bird is aged from the details of its feathers. Today, as well as ringing 17 new birds including song thrush and blackcap (see pics below), whitethroat, willow warbler, chiffchaff and chaffinch, we recaptured 11 birds, including one smart sedge warbler.

Adult male blackcap
Check out all the different feather types round his face!


Song thrushes are one of my favourite birds!