OSIECK ER (1975) On the occurrence of Treecreepers Certhia jamiliaris in 1972 and 1973. LIMOSA 48 (3): 188-196.

Eurasian Treecreeper Certhia familiaris familiaris The Treecreeper Certhia familiaris has been recorded only twice prior to 1972, viz. 27th Dec. 1967 and 24th Dec. 1971. Surprisingly, in the autumn and winter 1972/1973 a larg,e number of Treecreepers were reported, including 28 sight records, 25 trappings, and three birds found dead. These records have been reviewed using the criteria formulated by Osieck (1975). All records of birds found dead or trapped (Table 1) and 16 sight records of one or more birds (Table 2) could be accepted. All birds examined in the hand have been referred to the race familiaris from northern Europe and most birds seen showed the charaoters of this race. This influx coincides with high numbers of migrating Treecreepers at bird 'Stations in Finland, Sweden, Estonia, Latvia and Poland (Table 3) and numerous reoords of the nominate race in Denmark and northern Germany. In the Netherlands most recOJ:1ds were in the northern half of the country (Fig. 2). There are no records of this race in Belgium and only one in Great Britain. In 1973 migrating Treecreepers were also numerous in northern Europe (Table 3) but only one was trapped in the Netherlands and there were no sight records. Apparently the southwest limit of the winter range crossed the Netherlands in 1972, but in 1973 the migration extended less far southwestward. The occurrence of migrating Treecreepers coincides with exceptionally large numbers of Goldcrests during migration in northern and western Europe. Possible causes for these mov'ements will be treated in another paper

[free pdf] [dutch summary]