Northern Gannet, Morus bassanus

Northern Gannet
Northern Gannets are cold-water sulids, the family that includes the more warm-water-inclined boobies; they are found in the North Atlantic and the Eurasian shore of the Arctic Ocean. This one, present since 2012 at the Farallons where I took this picture in 2014, and also seen occasionally in San Francisco Bay, is the only one of its species ever reported in the Pacific Ocean. It is believed to have crossed from the Atlantic by way of the Northwest Passage, recently subject to thaw as a result of climate change. The bird has engaged in nest-building (as here) and other attempts to attract a mate that, sadly, are unlikely ever to meet with success. Its sex is not known.