Cory’s Shearwaters off Lanzarote
Ever since the Cory’s Shearwater complex got split, there’s been a lot of debate regarding some tricky individuals. Birds with intermediate features have been reported from both breeding and wintering areas and the variation within Cory’s and Scopoli’s seems to be unclear yet. All the birds included in this collection were seen in early September off Lanzarote, Canary Islands, so they are all meant to be Cory’s. Notice, for instance, how frequently they show white-tongues in P9, which are surprisingly long in some cases. The variation in underwing markings is also quite large and its assessment from photos is somewhat light-dependent. Bill depth and overall structure can be tricky too without any references. All these features should be analysed altogether in order to clinch the id, and still some individuals must remained unidentified.
