Het voorkomen van de Steenloper, Arenaria interpres (L.), en de Paarse Strandloper, Calidris maritima (Brünnich), in België en Zeeuws-Vlaanderen (Nederland)
Becuwe, M. (1972). Het voorkomen van de Steenloper, Arenaria interpres (L.), en de Paarse Strandloper, Calidris maritima (Brünnich), in België en Zeeuws-Vlaanderen (Nederland). Stentor 10(4): 16-64
In: Stentor. Jeugdbond voor Natuurstudie en Milieubescherming: Gent. , meer
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| Abstract |
This paper deals with the occurrence of the Turnstone and the Purple Sandpiper as passage migrants and winter visitors in Belgium and Zeeuws-Vlaanderen. An essential aspect of this area is the fact that both the feeding-grounds (Photographs I and 2) and the high tide refuges (Photographs 3-6) are man-made environments: breakwaters, piers and a variety of wooden and masonry constructions. The « heavy coastline» on Map I indicates the breakwater habitat on the sandy beach of the North Sea. The distribution of the Turnstone and the Purple Sandpiper is shown in Table II: dots indicate places where and periods in which the species is constantly present and circles where it is an irregular visitor. Four districts are distinguished: I: the beach district of the North Sea; II: the marine district of the Westerschelde; III: the brackish district of the Westerschelde; IV: the interior. Total numbers of the two species which were counted in the months January to April of 1968-1970 in the beach district of Belgium: 325 to 370 Turnstones and 100 to 180 Purple Sandpipers; in the beach district of Zeeuws-Vlaanderen : 170 to 325 Turnstones and 15 to 55 Purple Sandpipers. Fluctuations of the number of Turnstones in the beach district: - Single birds arc recorded during the first fortnight of July at places where they did not summer. - From mid-July onwards the fall migration starts clearly; the numbers gradually rise till November-December. (Migration peaks in autumn are absent in the beach district, though from mid-July to end-September single Turnstones are regulary seen in the Benedenschelde area and inland, up to 100 m altitude. We suppose that the strongest passage south occurs from mid-July to end September but that in the beach district most migrants pass unnoticed). Winter visitors are most numerous from mid-February to mid-April. The emigration of the wintering population starts at mid-April. By the end of May, the Turnstone has disappeared from the breakwaters and remains absent during six weeks. (Here again, migration peaks in the beach district are absent, although a few Turnstones appear during that period in the Benedenschelde area and inland. The same explanation as for the fall migration is put forward). In June, single birds are regular non-breeding summer visitors. Fluctuations of the number of Purple Sandpipers in the beach district: from mid-July onwards, the first Purple Sandpipers can be observed. Even at the end of September and in early October only single birds or very small groups are present. The main wintering population arrives from mid-October to early December. Only once, a small migration peak was noticed between mid-November and the end of December. From December to mid-April the population remains fairly constant. Spring emigration begins in the second fortnight of April and lasts to the third week of May. Clear culminating points of spring passage have never been observed. |
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