. Bulletin of the British Ornithologists' Club. Birds. L. M. Gonzalez et al. 90 1989 109(2). C=» Figure 1. Ranges (shaded) during the 19th century of the Spanish and Eastern Imperial Eagle Aquila heliacajadalberti in western and eastern Europe. Key of localities outside the shaded range Localities of skins of adults (•), non adults (O) and clutches (I) deposited in museum collections; and records of nests or adults in the breeding season (A) and non- adults (A) from the literature and the authors' own data. the breeding of Aquila adalberti in these regions have been found, while so
. Bulletin of the British Ornithologists' Club. Birds. L. M. Gonzalez et al. 90 1989 109(2). C=» Figure 1. Ranges (shaded) during the 19th century of the Spanish and Eastern Imperial Eagle Aquila heliacajadalberti in western and eastern Europe. Key of localities outside the shaded range Localities of skins of adults (•), non adults (O) and clutches (I) deposited in museum collections; and records of nests or adults in the breeding season (A) and non- adults (A) from the literature and the authors' own data. the breeding of Aquila adalberti in these regions have been found, while some data for Aquila heliaca do exist. Also, although most authors made no comment about the specific identity of Imperial Eagles from these countries, those which did so ( Dresser 1873, in France and Loche 1867, in Algeria) said they were Eastern Imperial Eagles. If so, the breeding population of Aquila heliaca in western Europe could be partially migrant as in eastern Europe and Asia (Dementiev & Gladkov 1966, Cramp & Simmons 1980), making their way to Africa through continental Italy and Sicily to Cap Bon (Tunisia), as do other Central European raptors (Massa et al. 1979, Dejonghe 1980). This could explain the relatively important number collected along this route (Fig. 1). At present, this migrant breeding population has disappeared, but some wandering individuals, probably coming from eastern Europe, are observed from time to time (Cramp & Simmons 1980). There seems hardly any doubt that the breeding ranges of the Eastern and the Spanish Imperial Eagles were in contact in the last century, and even more probably earlier still, at least in western Europe and probably in northern Africa. Such geographic contact (parapatry) would allow reproductive exchange and the possibility of hybrids. However, we have not detected a single specimen with intermediate plumage attributable to a hybrid in the 248 skins we have examined, and reference to hybrids does not appea
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbirds, bookyear1893
