Volume 49, No. 2

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Field separation of Cory's Calonectris borealis and Scopoli's C. diomedea Shearwaters by underwing pattern


1FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Rondebosch 7701, South Africa (
2Fauna and Flora Service, Generalitat de Catalunya, Provença 204, 08036 Barcelona, Spain


FLOOD, R.L. & GUTIÉRREZ, R. 2021. Field separation of Cory's Calonectris borealis and Scopoli's C. diomedea Shearwaters by underwing pattern. Marine Ornithology 49: 311 - 320

Received 08 May 2021, accepted 16 June 2021

Date Published: 2021/10/15
Date Online: 2021/10/14
Key words: Cory's Shearwater, Scopoli's Shearwater, Calonectris shearwater identification


The genus Calonectris contains four species: Streaked Shearwater C. leucomelas (which breeds in the North Pacific mainly on islands off Korea, Japan, and Taiwan), Scopoli's Shearwater C. diomedea (which breeds mainly in the Mediterranean Sea), Cory's Shearwater C. borealis (which breeds mainly on islands in the Northeast Atlantic Ocean), and Cape Verde Shearwater C. edwardsii (which is an endemic breeder of the Cape Verde Islands). In this study, we were concerned with the field separation of the cryptic pair Scopoli's Shearwater and Cory's Shearwater, only briefly considering the more easily recognised Streaked Shearwater and Cape Verde Shearwater. Background information is summarised in Appendix 1, available on the website).


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