Thursday, 15 September 2011

Getting in a final round

There is a chill in the air this morning as we arrive in the pre-dawn gloom. The pits feel strangely still, a sign perhaps that summer has reached its end. We are here, among the reedbeds and lagoons, to set our nets for birds on the last of the summer’s netting sessions. Every ten days or so throughout the summer we have set our nets in fixed locations, with the aim of catching and ringing warblers, tits and finches as part of a wider project. All over Europe there are volunteers doing what we are doing, catching and ringing birds for science and conservation.

The nets are made of a lightweight material, the mesh sufficiently loose and dark that you soon lose sight of the nets against the vegetation. Strung throughout each net is a series of horizontal threads, which produce ‘shelves’ within the net. A small bird, flying into the net, drops into the pocket formed by the shelf and is held gently until we extract it for ringing. It may seem a bit undignified but it does no harm and provides important information on bird movements, longevity and survival rates.

It takes nearly and hour to set all of the nets and, just before light, we go round them again to open up for catching. Already there is some activity, though little in comparison with earlier in the season when the site was packed with breeding birds. The soft calls of Reed Bunting and Pied Wagtail can be heard from one of the reedbeds. These are roosting birds that have come together to spend the night in the relative safety of the reedbeds. With a chill in the air we check the nets every fifteen minutes, removing the birds we have caught and placing each in its own cotton bag.

Once back at the cars, where we have set up our ringing station, we process each bird in turn. Each is identified and then the appropriate ring for that species is selected and fitted. The rings are made of a soft, lightweight metal alloy and each carries a unique number and the address of the British Museum. If the bird is caught again, or found somewhere else, then we will know its history. We examine the plumage to work out its age (most birds moult in a predictable way that enables us to differentiate between old and new feathers) and its sex, before assessing weight and body condition. All done, the bird is released. Ringing provides a unique opportunity to see birds in the hand, to really appreciate their form and structure, and I feel very privileged to contribute to our understanding in this way.

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