Tuesday, October 18, 2011



What the heck are these "procellaria petrels?" They are not in my North American bird field guides! Procellaria petrels are generally considered intermediate between the Calonectris shearwaters (Cory's and Streaked) and Pterodroma petrels (Cook's and Great-winged as examples), having features of both groups.

Recent reports of WHITE-CHINNED PETRELS (Procellaria aequinoctialis) off the coast of California have exploded in the news. Below, is Todd McGrath's image of the October 16, 2011 White-chinned Petrel taking flight near the Cordell Bank on a pelagic trip at Bodega Bay. Image copyright, Todd McGrath. Please do not use without permission.
Nope, these seabirds can not be found in the two most frequently used North American field guides: The Sibley Guide to Birds and National Geographic Field Guide to the Birds of North America. Most of the records for these seabird are relatively new to North America. Field guides will catch up, one day. Meanwhile, the serious seabirder will need to consult a more specialized tome for more detailed information. At the moment, I'd recommend Albatrosses, Petrels & Shearwaters Of The World by Onley & Scofield. While this book has serious faults, especially with regard to west coast seabird records, it does provide the basic information for range, field identification and some natural history of these seabirds.

Procellaria petrels comprise five species that are generally dark in coloration. Only the Grey Petrel has white underparts. The others, White-chinned, Parkinson's, Spectacled and Westland are overall dark. Sometimes, these seabirds are mistaken for Flesh-footed Shearwater, which is also a dark seabird, especially at a distance. The White-chinned Petrel is circumpolar throughout the Southern Ocean. White-chinned Petrels are the largest all-dark petrel. It breeds on the Falkland Islands and South Georgia, among other islands. It was known as the "shoemaker" at South Georgia by whalers because of the sounds it makes, much like a sewing machine. On a recent trip to South Georgia, I was able to hear these sounds! White-chinned petrels are known to be gregarious and follow fishing boats. Their diet includes krill, squid and fish. It is classified as a Vulnerable species by BirdLife International because of suspected rapid declines. Very high rates of incidental mortality in longline fisheries are suspected in recent years. This petrel has been tracked and data can be viewed at The Global Procellariiform Tracking Database.

Your own research will undoubtedly turn up additional information on these fascinating seabirds. Definitely worth learning about!

Hope to see you out there!
Shearwaters & Auklets & Procellaria Petrels Forever,
Debi Shearwater

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