Hitherto treated as conspecific with G. nilotica, but differs in its considerably larger size, with effect size for bill 3.69 (published data#R; score 2); differently shaped bill, with culmen more decurved and negligible gonydeal angle (2); nomadic, opportunistic and kleptoparasitic behaviour decoupled from tightly scheduled migration patterns (1); paler grey upperparts (1); more extensive black patch around the eye and ear-coverts in winter (1). Monotypic.
Australia. In winter also N to S New Guinea.
Food and feeding
Status and conservation
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