BEAUFORT LF, DE & KLOMP, H (1960) Annual Report on the Vogeltrekstation for 1959. LIMOSA 33 (3): 73-89.

Experiments and ringing activities During the years 1956-1959 nearly 1500 ringed teals have been displaced to Switzerland, after being caught in August and September in a duck-decoy in the province of Friesland. The teal very probably interrupts its autumn migration on the favourable feeding grounds in Holland before going to the ultimate winter quarters. The experiment was carried out to see whether displaced birds were able to return to the temporary summer residence by using goal orientation. However, the recoveries of both juveniles and adults were scattered around the release point. Those of the juveniles pointed mainly in two opposite directions: southwest and north-east. In 1959 we started a new displacement experiment with starlings. A thousand ringed birds were released at Barcelona, Spain, near the valley of the river Ebro. which constitutes a very favourable winter quarter for starlings. The birds were displaced when halfway on their migration route. The question arises whether the birds will finish their migration under the influence of the favourable wintering habitat. It can be seen in fig. I that most of the birds continue their migration. Hence, it is probable that the end of the migration route is determined mainly by internal factors. Two recoveries of adult birds, 200 and 1000 km north of the release point, are very interesting. They confirm the results of former displacement experiments with starlings to Switzerland, which showed a goal orientation in adult birds. The experiment will be continued in 1960. At the fowling-yard of the Vogeltrekstation near the Hague 10.221 birds were ringed in autumn. The numbers of birds ringed under the Leiden ringing scheme showed a tremendous increase (fig. 2). Field o.bservations The camp for training students in observing visible migration was held at Oostvoorne. This locality had been chosen to study the influence of the estuaries on chaffinch and starling migration. As can be seen from fig. 3 and 4 chaffinches are strongly deflected to the south-east. The study of the standard directions of the Scandinavian chaffinches in various parts of its area of passage in autumn was continued. Successful observations were carried out near Blaavands Huk and in West Seeland (fig. 5). At Blaavands Huk the standard direction could be determined to be mainly S by W. It might be that this direction had been induced by the direction of the coast line. However, about 30 km from the shore, inland the same direction prevailed. In W. Seeland the mean standard direction was observed to be SW by S. All data concerning the standard direction of the Scandinavian chaffinch are shown in fig. 6. They suggest that the chaffinch reaches its winter quarters in England by means of a round about route around the North Sea. This provisional conclusion is supported by ringing results, which indicate that chaffinch migration across the northern part of the North Sea does not occur or is very rare. The observations at Blaavands Huk suggest that Norwegian chaffinches cross the Skagerak in a southern or south-eastern direction. They then pass through Jutland in a southern standard direction, turn to the WSW or W in Holland, and to the WNW in Northern France. In these countries they join with the Swedish birds. A standard direction changing in this way is neither in accordance with a simple one-directional navigation, nor with goal orientation. To study the problem further observations in the southern part of Norway and the German Wadden district have been planned for 1960

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