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Migrant coal tit flock rising

 

There has been much talk this year about the large numbers of migrant coal tits. Invasion-type movements of this species are not rare but this year it is clearly  on a larger scale than usual and probably the largest in recent decades. The last more serious coal tit migratory movement was in the autumn of 2013 and culminated in Kabli, with a day count of more than 10 000 noted by Margus Ellermaa.

 

The Puise peninsula in Läänemaa is a good gathering place for terrestrial birds in autumn and in connection with the movements of coal tits migration observations have been made there on several mornings  this autumn. After a couple of rainy days there was again reason to go out today and with Alpo Koukila we made a 5-hour watch (between 6.40 and 11.40).

 

The morning did not disappoint us – as the result of the 5-hour migration watch we got a black tit total count of just over 50 000 individuals which also is a record day total ever counted in one observation location in one day for this species . Migration was particularly intense during the first observation hour when altogether 22 000 coal tits passed. The largest flocks had about 1500 birds although at times there was actually a continuous flow of several flocks moving as a single flock. All larger flocks were counted by both observers for the sake of accuracy and as the count result we used the average of the two observers. It should be noted that even with very large flocks our estimates did not differ very much – usually 5%, seldom up to 10%.

 

During the following hours the migration subsided – in the second observation hour ”only” 12 000, and in the following even fewer. The total in the last observation hour was less than 2 000 birds.

 

There can evidently still be good coal tit migration days during the next few days because migration usually peaks in the 1st decade of September. But the current morning may still remain the best of the season.