SCVAS Trip to Farallon Islands

Saturday, August 13, 2011, Led by Bob Power, Matthew Dodder, and David Wimpfheimer

Trip Map

Trip Notes

Notes submitted to the California Bird Records Committee by David Wimpfheimer:

"OBSERVATION

On August 13, 2011 [David] was a leader on a birding trip to the Gulf of the Farallones National Marine Sanctuary. The other leaders included Mathew Dodder and Bob Power. The trip was sponsored by the Santa Clara Valley Audubon Society. We were on the Superfish, a boat [David] have worked on dozens of times. [David] have led over 300 whale watching trips to the Farallones since 1984. Most of these trips focus on whales, but I am always trying to view as many seabirds as possible.

We only saw a few Sooty Shearwaters in the shallow water east of the island. We were not chumming.

We started throwing out popcorn about three miles west of SEFI as we started traveling over the deeper water. It wasn’t long before many gulls followed the boat. Black-footed Albatross, Northern Fulmars, Sabine’s Gulls and shearwaters soon were attracted to our vessel.

Many of the passengers stayed at the stern to look over the birds following the Superfish. [David] studied those birds, but also walked around the boat to look for any other species that might elude us. A little before 1:00 pm I was standing on the starboard side of the boat looking out towards the west or southwest. [David] saw a bird with a flight behavior that immediately made me examine it more closely with my binoculars. [David] was looking through 10 X 42 Bushnell Elites. The bird was flying almost directly up from the water and then turning quickly and driving back towards the surface. The bright white undersides might have suggested a Buller’s Shearwater, but [David] recognized this flight as typical of a Pterodroma.

It was fortunate that Matthew Dodder was standing close by. [David] got him on the bird and explained that [he] thought it was a Pterodroma. [David] also yelled out that everyone should try to see this bird, that it was something different. [David] also tried to photograph the bird as it looped up and down. The sea conditions made it hard to see the bird continuously as it dipped behind the swells and veered away from the boat before flying closer. We were able to see, study and photograph the bird for 60 to 70 seconds. It was at a distance of 30-50 meters. The bird flew off and was not seen again. [David] went over in [his] mind what [he] had just seen:

  • The rapid, high arching and looping flight and stiff, strongly angled wings strongly suggested that it was a Pterodroma.
  • The bird was not flying like a shearwater.
  • The dorsal side of the wings back and tail were a uniform dark gray.
  • The belly was fully white and the undersides of the wings were bright white except for a dark blackish mark that extended from the leading edge of the wing a bit on the ventral side of the wing.
  • The area around the eye was very dark, almost black. There was a dark gray post ocular mark that extended down from the nape.
  • The all-dark bill was shorter and thicker than that of a shearwater.
The bird was about the same size as the Sooty Shearwaters that were nearby for comparison.

In the cabin [David] then looked at National Geographic and Sibley guides which helped to eliminate Cook’s Petrel since the bird we just saw had an all-dark back. Also our bird had a dark post ocular mark that Cook’s Petrel lacks. These marks helped Matthew and I identify our bird tentatively as a Hawaiian Petrel. [David] wanted to look at the photographs more and consult Harrison’s Seabirds, which [David] did when [David] got home. After looking at Harrison’s [David] also eliminated Juan Fernandez Petrel as our bird had an all dark tail and rump.

CONDITIONS

Winds were about 14 – 16 mph from the northwest with six to eight foot seas. The motion made it difficult for some passengers to use binoculars and cameras. However, as we motored more towards the south with a following sea, the conditions were much smoother and allowed us to enjoy better views of the Hawaiian Petrel and other birds."