A Debreceni Déri Múzeum Évkönyve 1965 (Debrecen, 1966)

Tanulmányok - Kovács Béla: Data on the avifauna of county Hajdú-Bihar

Béla Kovács Data on the avifauna of county Hajdú-Bihar Data are published on the avifauna of Country Hajdú-Bihar and the adjoining borderland making oecologically and geographically part of the territory. Based on the research work of the author and on literature 106 species of birds are described. The 106 species make only part of the avifauna of the country as the fauna list of Hortobágy made up in 1947 mentions 246 species of birds. The present territory of County Hajdú-Bihar is 629 X 291 hectares, about one sixth of which (136 X 748 hectares) are hayfields and meadows belonging for the most part to the Hortobágy and forming the largest puszta in Hungary. This steppe, together with the parts reaching beyond the borders of the county, cover about 400,000 hectares. As to the life of birds, this is an unbroken unit also today. The water surface of the county, the fish-ponds on the borderland included, is spreading over 7,000 hectares, out of which more than 2,027 hectares are covered by reeds. The county is poor in wooded areas (46,068 hectares) and the continous streches reach beyond the area of the county. Part of the birds using the woods for nesting also concentrate on the steppe. From the point of ornithology the following have been included in the county: a 20-25 mile stretch of the river Tisza form Tiszacsege to Tiszadomb, parts of the Hortobágy reaching beyond the county, first of all Kunmadaras puszta and the fish-ponds of Biharugra at the southern border of the county. The avifauna of the latter shows some differences in comparison with the birds of similar fish-ponds in the Hortobágy. Since the liberation our county has seen dramatic changes: modern large-scale farming has been graning ground, new culture cenoses have been created. The changes taking place in the cenoses also today (new fish-ponds, green-belts, irrigation, etc.) being changes in structure and in production affect also the density, nesting, feeding and other oecological conditions of birds. The changes are reflected partly in a decreased number of species and, on the other hand, a larger possibility of proliferation in some species. Avifauna being a most sensitive indicator of changes in the life of cenoses, its observation with a view to agriculture, nature conservation and theory (biological protection, proliferation of harmful birds, protection of birds important for game husbandry) is of eminent significance. This purpose is served also by the authors new fauna inventory of the county, under preparation. Among the significant changes in the avifauna of the county three deserve special attention: 1. With the growing number of fish-ponds, the number of some rare species nesting in reed and feeding from the ponds, goes increasing. Before the war these birds nested in considerable numbers in the primaeval marshes of the Great Plain only in the last century. With the increasing of artificial water surfaces feeding possibilities have improved and they nest in great numbers again in spite of being pretty much disturbed. Their proliferation, as seen, is a function of food and water surface in addition to systhematical protection. Their decrease in number and extinction was not a result of their considerably disturbed conditions. The species belonging here are: Cormorant (Phalacrocorax carbo). First data of its nesting in the county in this century: Ároktő, June 10th, 1965; Tiszadob, 1965. Squacco Heron (Ardeola ralloides). Nesting data: Tiszadob, 1963, Ároktő, 1964; 3 to 32 pairs. Great White Heron (Egretta alba). Nesting data: Hortobágy Fish-Pond (1961, 1962, 1963, 1964, 1965) 1 to 4 pairs. Little Egret (Egretta garzetta). Nesting data: Egyek 1964; Tiszadob,1963, 1964, 1965; Ároktő, 1964, 1965 (6 to 54 nests). 380