On August 17th a group of birders set off of Sausalito for another run into the Deep Waters off of San Francisco county, especially the Pioneer Seamount some 55 miles offshore. We were treated with good weather all day, with high overcast and minimal swell, with some light gusts of wind.
We left on a southwestern trajectory out of the Golden Gate. The huge numbers of Sooty Shearwaters recently present off our coast continued, along with a nice number of Jaegers including a surprisingly in-shore Long-tailed. As we neared the shelf edge activity started to pick up and our first Tufted Puffin came alongside a South Polar Skua. Crossing over the Canyon proper, we found some of the Storm-Petrels recently noted by the Alvaro's Adventures trip a few days prior, including high numbers of Blacks as well as Ashies.
Riding out the canyon screams went out over our first two pelagic "land" birds: a juvenile Brown-headed Cowbird and a juv Least Sandpiper. While the expected landbirds still dominate on pelagic trips, seeing passerines and shorebirds out here is a little bit like seeing them on the Farallon Islands, and there is always a very real chance for rare migrants out there.
The canyon held good numbers of Buller's Shearwaters, Sabine's Gulls, Storm-Petrels, and Humpback Whales as well as a good smattering of Murrelets. The boat got great views of two seperate GUADALUPE MURRELETS as well as a single Scripps' and a few others left unidentified. This has likely been the best year in the last couple decades for Guadalupe Murrelets off of the Bay Area, and on this day we actually found more Guads than Scripps's(!). A pair of Common Terns went by, which surprisingly outnumbered Arctics on this day.
At around 10:30 we left the more productive shelf-edge waters of the canyon and headed off into the "oceanic desert" that starts about 40 miles offshore. These waters, which earlier in the year hosted large numbers of Cook's Petrels, are relatively infrequently-surveyed, and it is not always clear what's going on where when you get that far off. Anyways, one of the few consistent features of these far offshore waters are the presence of Leach's Storm-Petrels, which are relatively rare within 30 miles of shore. Sure enough, a smattering of Leach's appeared when we entered this region: a couple obvious pale-rumped likely northern-breeding birds and a few more subtle dark-rumped "Chapman's" Leach's from the south. The "chapman's" have been an interesting feature of this year, and have shown up even by the Pioneer Canyon this year. This taxon's status this far north is clouded by the lack of data in far offshore waters, but it is likely infrequent at best as a visitor to our region.
Coming hand-in-hand with the dark-rumped Leach's came a single FLYING FISH seen by several on board. While present this year (almost half a dozen separate boats have seen them off of the Bay so far this year) their presence in this region is nonetheless remarkable, and represents an unprecedented incursion this far north.
We topped the seamount and spent a couple hours trolling around the deepwater both on the summit and on the eastern flank searching for pockets of activity. Cetacean activity was excellent, with many Fin Whales, several Blue Whales and a pod of Common Dolphins. Birds were few and far between out there today, with large numbers of Red Phalaropes but only small numbers of Storm-Petrels, Sabine's Gulls and shearwaters otherwise.
As we started to come in, entering 50 then 45 then 40 miles offshore, activity started to pick up again, and drastically. There were no obvious underwater features or temperature breaks, but about 42 miles west of Montara the amount of life was truly spectacular. Over just a 30 minute span we flushed several flocks of multiple hundreds of Buller's Shearwaters each, numbering over 1000 individuals in total. It is worth noting that while Buller's not infrequently come in large numbers to this area in September and October, having such a concentration in August is quite unusual. We were rushing to get back to the dock, but the numbers of Shearwaters and other seabirds was quite impressive nonetheless. During this time, a bright (female?) Yellow Warbler started following the boat, and we picked up a couple more Guadalupe Murrelets. Not long after this the rod on board started to whir and the captain and deckhand spent the next half hour fighting and then landing a 200 lb Bluefin Tuna! A pretty impressive end to a nice day out there.
On our way back in we swung by the "W" Buoy east of the farallons and got good looks at the two continuing NAZCA BOOBIES. After soaking in the boobies we headed inshore. As we drew close to shore right off San Francisco we were met to an incredible spectacle of 50,000+ Sooty Shearwaters foraging right offshore.
It is turning in to quite the interesting year offshore with certain warm-water species (Guadalupe and Craveri's Murrelets, Cook's Petrels, Black and Least Storm-Petrels etc) appearing in our region in much higher than normal numbers while some other species (e.g. Albatross) seeming to be relatively absent.
If you are interested in future such trips message me privately. There are also quite an assortment of options for pelagics off of the West Coast this fall.
