Wednesday, 23 December 2009

Winter Atlasing


We are now in the third and final year of the Winter Atlas fieldwork in Spain (organised by SEO/BirdLife). It has been a real highlight of the winter for me. I am doing seven 10 km squares and visits to each entail about a six hour walk along paths or tracks, counting every single bird seen or heard and estimating whether it is within 25 metres of the path or not. Add to this a description of the habitat every fifteen minutes and you can imagine the amount of information that is being gathered. This then gets put on the computer and sent on-line to Madrid. I think that the results will be fascinating, giving us a picture of not just where different species occur in the winter across Spain, but also their relative abundance and habitat preferences.

The planning is quite complicated. There is no point doing this type of survey work if it is raining, very windy or foggy...because this would create bias in the detectability of birds (they will be harder to count). I also avoid going out on the days that there will be hunters out shooting. I do not want to put myself at risk quietly walking down small paths in wooded areas where shooting is going on: this means weekends and Thursdays are out (the days that hunting takes place here in the winter).

At the personal level it offers discoveries on many levels. To cover each 10 km square thoroughly takes me along paths and tracks I have never walked on before, I discover routes along valleys and across mountains...it truly does take me off my regular birding "beaten track" which is no bad thing. Counting everything has also given me a much better idea of the status of birds locally: be it the number of wintering Bluethroat and Snipe on the ricefields or Blackcaps in the olive groves. I have also come across birds which are highly under-recorded in this area, such as Woodcock and Bullfinch (considered quite a rare winter visitor, but I have found it on three of my squares so far).

There are also the great memories that come from seeing quite special things, even of common birds: a Dartford Warbler searching for trapped tiny insects on a bank of snow, a delightful party of eight Common Chiffchaff feeding on the ground together, a flock of 80 Serins that one could hear from across a huge field...

Yes, I am looking forward to this third field season of Winter Atlas work very much.

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