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Summary The results of an expedition to Bulgaria during May and June 1960 are described. The majority of observations were made in the eastern regions of the Danube, the Dobrudja and particularly the lakes and woods of the Black Sea coast. Although, apart from the national scientific bodies, there is as yet little apparent interest in ornithology as such in Bulgaria, the laws protecting wild birds and the provision of sanctuaries are shown to be adequate. There is, however, evidence that the populations of certain larger birds such as pelicans, vultures and eagles have declined seriously, chiefly as a result of intensive agriculture, land reclamation, the annual cutting or burning of reed-beds or the use of poison-bait to control wolves. Other bird species are shown to have extended their ranges and some to have increased in numbers. Comparisons are made with the observations of earlier writers. Comments on observed migration are included in the Systematic List, which embraces 220 species, of which 205 were recorded in the course of the expedition. |
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