Fea's Petrel - Taxonomy

Taxonomy

The gadfly petrels in the genus Pterodroma are seabirds of temperate and tropical oceans. Many are little-known and poorly studied, and their often similar appearance has meant that the taxonomy of the group has been rather fluid. The forms breeding in Macaronesia on Madeira, Bugio in the Desertas Islands, and in the Cape Verde archipelago were long considered to be subspecies of the southern hemisphere Soft-plumaged Petrel P. mollis, but differences in size, vocalisations, breeding behaviour and mitochondrial DNA analysis showed that the northern birds are not closely related to P. mollis, and that the Bermuda Petrel or Cahow may be the closest relative of the Macaronesian birds. Sangster recommended establishing Zino's Petrel on Madeira and Fea's Petrel on the Desertas and Cape Verde as full species, and the species split was accepted by the Association of European Rarities Committees (AERC) in 2003. More recently, some authorities have further split Fea's Petrel, separating the Desertas Islands breeding birds from those in the Cape Verde archipelago.

Sangster estimated that the two Macaronesian species they diverged at the end of the Early Pleistocene, 850,000 years ago, although the methodology used to establish this time scale has subsequently been questioned. An analysis of feather lice from Fea's Petrel's Pterodroma feae deserti from Bugio Island and Zino's Petrels from the Madeiran mainland showed that there were marked differences between the two seabirds in terms of the parasites they carried, suggesting that they have long been isolated, since lice can normally only be transferred through physical contact in the nest. The species on Zino's Petrel are most similar to those of the Bermuda Petrel, whereas Fea's Petrel's lice are like those of Caribbean and Pacific Pterodromas. This suggests that despite the close physical proximity of the two species of gadfly petrel found in the Madeiran archipelago, they may have arisen from separate colonisations of mainland Madeira and, later, the Desertas Islands.

This bird is named after the Italian zoologist Leonardo Fea.