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This report reviews the state of the California Current System (CCS) between winter 2012 and spring 2013, and includes observations from Washington State to Baja California. During 2012, large-scale climate modes indicated the CCS remained in a cool, productive phase present since 2007. The upwelling season was delayed north of 42°N, but regions to the south, especially 33° to 36°N, experienced average to above average upwelling that persisted throughout the summer. Contrary to the indication of high production suggested by the climate indices, chlorophyll observed from surveys and remote sensing was below average along much of the coast. As well, some members of the forage assemblages along the coast experienced low abundances in 2012 surveys. Specifically, the concentrations of all lifestages observed directly or from egg densities of Pacific sardine, Sardinops sagax, and northern anchovy, Engraulis mordax, were less than previous years’ survey estimates. However, 2013 surveys and observations indicate an increase in abundance of northern anchovy. During winter 2011/2012, the increased presence of northern copepod species off northern California was consistent with stronger southward transport. Krill and small-fraction zooplankton abundances, where examined, were generally above average. North of 42°N, salps returned to typical abundances in 2012 after greater observed concentrations in 2010 and 2011. In contrast, salp abundance off central and southern California increased after a period of southward transport during winter 2011/2012. Reproductive success of piscivorous Brandt’s cormorant, Phalacrocorax penicillatus, was reduced while planktivorous Cassin’s auklet, Ptychoramphus aleuticus was elevated. Differences between the productivity of these two seabirds may be related to the available forage assemblage observed in the surveys. California sea lion pups from San Miguel Island were undernourished resulting in a pup mortality event perhaps in response to changes in forage availability. Limited biological data were available for spring 2013, but strong winter upwelling coastwide indicated an early spring transition, with the strong upwelling persisting into early summer.

Abstract--The increase in harbor seal (Phoca vitulina richardsi) abundance, concurrent with the decrease in salmonid (Oncorhynchus spp.) and other fish stocks, raises concerns about the potential negative impact of seals [...]

Abstract--Marine mammal diet is typically characterized by identifying fish otoliths and cephalopod beaks retrieved from stomachs and fecal material (scats). The use and applicability of these techniques has been the [...]

Abstract--Along the west coast of the United States, the potential impact of increasing pinniped populations on declining salmonid (Oncorhynchus spp.) stocks has become an issue of concern. Fisheries managers need [...]

Large cetaceans were heavily impacted by commercial whaling, so relatively little is known about their biogeography prior to historic times. On California's Channel Islands, maritime peoples hunted dolphins and porpoises for millennia, but ethnohistoric data suggest that larger cetaceans were not hunted. The Island Chumash scavenged beached whale carcasses for food and technological purposes, however, and the bones of large whales are relatively common in many Channel Island shell middens. Cetacean bones from such sites provide unique opportunities to document the ancient distribution and human use of larger whale species, but many bone fragments are not identifiable to the genus or species level based solely on osteological characteristics. Here, we report genomic data for two whale bones recovered from a 5850 year old shell midden on San Miguel Island. Both were identified as fin whale, the second largest of the great whales. Our analysis provides points in space and time for the distribution of fin whales in the past, but a wider identification of whale bones from coastal archaeological sites can potentially expand such data for numerous whale species, adding significantly to an understanding of their distributions, ecology, and utility for humans in the past. [ABSTRACT FROM AUTHOR]