A Kermadec Petrel (Pterodroma neglecta) on Southeast Farallon Island

October 3, 2017

by Adam Searcy
On September 8th, 2017, I was finishing up the last shark watch of the evening at the lighthouse atop Southeast Farallon Island. At about 5:15PM, thick fog rolled in, so I shut down the watch and sheltered inside of the lighthouse to see if it would clear. It did not, so at 5:46PM, I stepped outside to head down the trail to the house. It had been a quiet day, bird-wise, so when I saw a dark bird flying in from the fog over Owl Chute (a small ‘canyon’ that runs south down Lighthouse Hill), I was immediately interested:
As I lifted my binoculars, the bird banked and showed off its structure: my brain clicked and said “Petrel!” (with a few more exclamations than that) and I immediately thought “But which species?” It didn’t appear to fit any of California’s ‘expected’ Petrels of the genus Pterodroma—none of which are expected to fly around the lighthouse atop Southeast Farallon Island in any sort of weather, much less dense fog. It certainly wasn’t a Cook’s (which are more boldly patterned in all plumages) and I didn’t think that an out-of-season (they normally occur in spring and early summer) and worn Murphy’s Petrel could look like this but I wasn’t entirely sure. This bird appeared deep brownish-gray overall with doubled pale flashes on the underwings and thin whitish shafts on the upper sides of the primaries, similar to some Jaegers. I quickly lifted my camera and snapped a few seconds worth of photos, then immediately lost the bird around the lighthouse. I loudly radioed everyone inside : “There’s a Petrel flying around the lighthouse!” (or something similar) to which I got some puzzled responses, including “A Storm-Petrel?” to which I said “No, a PETREL!”  I was walking rapid circles around the lighthouse, hoping that the bird would again emerge from the fog but it had departed back into the gloom before those at the house could make it outside.
Thankfully, I was able to capture some poor but identifiable photographs of the bird before it left, allowing us to consult references and confirm its identity:

The Kermadec Petrel has light and dark morphs, and this bird was one of the latter. The pale ‘double flash’ on the underwing visible in the cover photo at top and pale primary shafts on the upper wing in the photo above help differentiate dark morph Kermadec Petrels from similar species such as Solander’s and Herald Petrels, neither of which have been recorded in California waters.
This isn’t just a Farallon first, but is the first record for California and the continental United States (away from Hawaii). Kermadec Petrels breed on remote islands in the sub-tropical South Pacific, including the Kermadec Islands northeast of New Zealand and Juan Fernandez Islands off of Chile. Like many other seabirds, they range widely during the non-breeding season and are uncommonly recorded north to around 20 degrees off of Mexico’s Pacific Coast (Howell 2012).

Approximate Range of Kermadec Petrel (Birdlife International 2016) with Southeast Farallon Island indicated by a red star
Why did this bird show up here and on this date? I can’t know for certain, but I can speculate. It may have been related to the recent passage of Tropical Storm Lidia up the coast of Middle America which pushed some unstable weather into California along with a small influx of Magnificent Frigatebirds, a rare visitor that has been pushed north by tropical storm events in the past. But who knows what the truth is.
References:
Howell, S. N. G. 2012. Petrels, Albatrosses, and Storm-Petrels of North America: A Photographic Guide. Princeton University Press, Princeton, New Jersey.
BirdLife International. 2016. Pterodroma neglecta. The IUCN Red List of Threatened Species 2016: e.T22698027A93655794. https://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T22698027A93655794.en. Accessed on 19 September 2017.