2011-07-12

Migrating swifts in Swedish Lapland


Yesterday night Jan Holmgren and I returned to Hakkas in Swedish Lapland for recapturing some common swifts (Apus apus) to which we attached geolocators in 2010. It was with great pleasure we rejoined to meet with our friend and host Börje Wennström. This is the most northern colony of commons swifts we have been working at and a spectacular one as all of them live in wooden nestboxes made out of old tree trunks. Börje and his relatives and friends have produced all of the boxes on their own, and have set up more than 200 nest boxes for swifts in the villages. Some of the nest boxes are placed in the same trees and may have swifts breeding in all of them. A great interest in the breeding locations might be the lack of natural breeding sites in old trees in the forest and especially if the old trees with holes are cut at newly harvested forest plots. In northern Finland the common swifts are called "tjärsvala" (=tar swallow), as they live in abandonded woodpecker holes in old trees. Some of the good natural breeding sites may contain several pairs of swifts, and last year we visited a few such nesting sites. My only wish when I saw them was that more such trees shoould be saved in the forest, as they are VERY important to the birds and other animals.

The first swifts we caught this morning was the very fist one we caught last year in Börjes garden! In excellent shape and with the logger intact on the back. Eventually we discovered that also data were stored onboard which will enravel where the bird spent the winter as well as which migration routes it selected during autumn and spring. This spectacular start documented by a local journalist suggested that our next few days will be exciting!

Tomorrow is the time for my lecture in the next village Dokkas, in the very house of the swift nestor Arthur Leidgren.

Susanne

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