Het voorkomen van de Zeearend Haliaeetus albicilla rond Kampen in de afgelopen 100 jaar

For the eastern shore of Lake Ijsselmeer, near Kampen, records of White-tailed Eagles were collated from published sources, in addition to the information derived from (partly systematic) counts in the mid-2000s. No more than 1 White-tailed Eagle per year was recorded in 10 years between 1908 and 1939. Up to 4 birds per winter (usually 1-2) were annually present between 1946-55. In the 1970s, only 7 records have been registered (6x 1 bird, 1x 2 birds). A Norwegian eagle, ringed as nestling in 1977, was found dead (pneumonia) on 10 March 1979. In the 2000s, the number of observations increased steeply, with 12 records in 2001,12 records in 2002,42 records in 2003 and 14 records in the first half of2004 (presumably indicative of an increase in observation effort). These observations encompassed all months of the year, except April. How many individual birds were involved, is not known. In the winter of 2004/05, a single White-tailed Eagle in its second/third year of life stayed in the region. A colour-ringed Swedish bird was present in the winter of 2005/06, originating from a breeding site in eastern Sweden (ringed as nestling in 2002), Records were restricted to the period of 12 November through 23 February; an observation of an adult may have involved the Swedish bird. In the winter of 2006/07, three White-tailed Eagles were present between 19 September and 11 February, i.e. an adult, a third/fourth-year bird and a juvenile. In 2007/08, most observations were of an adult bird, but a second/third-year bird on 5 January indicated the presence of a second bird. The observations in the 2000s do not suggest an increase in the number of wintering White-tailed Eagles in the eastern Lake Ijsselmeer region as compared to the 20th century.