Diversity, distribution and dynamics of Larval Cephalopods off Northern California

Cephalopods are the fastest growing invertebrate, often putting on 3- 5 % of their body weight each day. Due to the nature of their diet, their body mass can be up to 80% protein, offering humans an easy and fast source of protein. This offers fisheries a new option to explore. The main problem behind wild-catching Cephalopods, is the issue of where they are. This study examined retrospective larval Cephalopod samples collected from 2009-2017 to examine trends in the diversity and distribution of the larvae. Notably, some of the collected data was taken during the warm water event that started in mid 2014 and persisted through 2016, the native species Octopus rubescens exploded in number during this event, as well as members of the Family Gonatidae. Future studies should expand the distance from the continental shelf sampled, as well as the depth sampled to get a wider diversity of larval size classes

Effect of Short-Term Exposure to Low pH and Low Dissolved Oxygen on the Swimming Performance of Juvenile Rockfish

Organisms living in coastal habitats off northern California coast are exposed to low pH and low dissolved oxygen water during strong upwelling events, but the effects of these events on coastal fishes is poorly understood. We examined the effects of short-term (1 to 24 hour) exposures to low pH (pH ~ 7.5) or low dissolved oxygen (DO; 50% O2 saturation) on the swimming performance of juvenile rockfish (Sebastes spp.). Juvenile copper rockfish (Sebastes caurinus) were collected from Trinidad Bay, and, following acclimation to laboratory conditions, were exposed to treatment conditions for intervals of 0 (control), 1, 2, 4, 8, or 24 hours. We measured critical swimming speed (uCrit)—a metric of swimming performance that integrates speed and endurance—by placing each fish into a swimming flume and increasing current speed according to a timed, stepwise sequence until exhaustion. Short-term exposures cause a decline in uCrit, with increasingly strong effect developing from 0-4 hours. Swimming performance remains depressed over longer exposures, but it is possible that recovery from initial handling stress might offset continued declines in swimming performance. Ongoing work is addressing a potential size-dependence in response to exposure, and will examine the effect of simultaneous exposure to low-pH/low-DO water, as these conditions naturally co-occur. Insights from this study address the potential ecological effects of upwelling events, which may have important demographic consequences for these ecologically and economically important species, as well as the potential consequences of increasing frequency, duration, and intensity of upwelling-driven exposures and increasing levels of global ocean acidification predicted under ongoing climate change

State of the California Current 2014-15: Impacts of the Warm-Water "Blob"

In 2014, the California Current (~28˚–48˚N) saw average, or below average, coastal upwelling and relatively low productivity in most locations, except from 38˚–43˚N during June and July. Chlorophyll-a levels were low throughout spring and summer at most locations, except in a small region around 39˚N. Catches of juvenile rockfish (an indicator of upwelling-related fish species) remained high throughout the area surveyed (32˚–43˚N). In the fall of 2014, as upwelling ceased, many locations saw an unprecedented increase in sea surface temperatures (anomalies as large as 4˚C), particularly at 45˚N due to the coastal intrusion of an extremely anomalous pool of warm water. This warm surface anomaly had been building offshore in the Gulf of Alaska since the fall of 2013, and has been referred to as the “blob.” Values of the Pacific Decadal Oscillation index (PDO) continued to climb during 2014, indicative of the increase in warm coastal surface waters, whereas the North Pacific Gyre Oscillation index (NPGO) saw a slight rebound to more neutral values (indicative of average productivity levels) during 2014. During spring 2015, the upwelling index was slightly higher than average for locations in the central and northern region, but remained below average at latitudes south of 35˚N. Chlorophyll a levels were slightly higher than average in ~0.5˚ latitude patches north of 35˚N, whereas productivity and phytoplankton biomass were low south of Pt. Conception. Catches of rockfish remained high along most of the coast, however, market squid remained high only within the central coast (36˚–38˚N), and euphausiid abundance decreased everywhere, as compared to the previous year. Sardine and anchovy were nearly absent from the southern portion of the California Current system (CCS), whereas their larvae were found off the coast of Oregon and Washington during winter for the first time in many years. Waters warmed dramatically in the southern California region due to a change in wind patterns similar to that giving rise to the blob in the broader northeast Pacific. For most of the coast, there were intrusions of species never found before or found at much higher abundances than usual, including fish, crustaceans, tunicates and other gelatinous zooplankton, along with other species often indicative of an El Niño. Thus species richness was high in many areas given the close juxtaposition of coastal upwelling-related species with the offshore warm-water intrusive or El Niño-typical taxa. Thus the California Current by 2015 appears to have transitioned to a very different state than previous observations

State of the California Current 2013-14: El Niño Looming

In 2013, the California current was dominated by strong coastal upwelling and high productivity. Indices of total cumulative upwelling for particular coastal locations reached some of the highest values on record. Chlorophyll a levels were high throughout spring and summer. Catches of upwelling-related fish species were also high. After a moderate drop in upwelling during fall 2013, the California current system underwent a major change in phase. Three major basin-scale indicators, the PDO, the NPGO, and the ENSO-MEI, all changed phase at some point during the winter of 2013/14. The PDO changed to positive values, indicative of warmer waters in the North Pacific; the NPGO to negative values, indicative of lower productivity along the coast; and the MEI to positive values, indicative of an oncoming El Niño. Whereas the majority of the California Current system appears to have transitioned to an El Niño state by August 2014, based on decreases in upwelling and chlorophyll a concentration, and increases in SST, there still remained pockets of moderate upwelling, cold water, and high chlorophyll a biomass at various central coast locations, unlike patterns seen during the more major El Niños (e.g., the 97–98 event). Catches of rockfish, market squid, euphausiids, and juvenile sanddab remained high along the central coast, whereas catches of sardine and anchovy were low throughout the CCS. 2014 appears to be heading towards a moderate El Niño state, with some remaining patchy regions of upwelling-driven productivity along the coast. Superimposed on this pattern, three major regions have experienced possibly non-El Niño-related warming since winter: the Bering Sea, the Gulf of Alaska, and offshore of southern California. It is unclear how this warming may interact with the predicted El Niño, but the result will likely be reduced growth or reproduction for many key fisheries species

State of the California Current 2012–13: No Such Thing as an "Average" Year

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

Marine Species

The 4.1 million square miles of ocean inside the 200-mile exclusive economic zone around the United States surpasses the 3.6 million square miles total land area within federal jurisdiction (Lindholm and Barr 2001). The coastal oceans contain a great diversity of habitat types and ecosystems. These habitats are associated with particular substrate features such as coral reefs, sea grass beds, rocky shores and soft-bottom habitats, and also with persistent oceanographic features such as frontal convergence zones and upwelling regions. Our marine ecosystems contain unique and rich biotas. At higher taxonomie levels, biodiversity is much richer in the marine environment than it is on land or in freshwater. For example, thirty-six out of thirty-seven animal phyla are represented in the sea (Groombridge and Jenkins 2002), and 64 percent of animal phyla are found exclusively there, whereas only 3 percent are confined to land and none are exclusive to freshwater (May 1994; Reaka-Kudla 1997). Marine ecosystems appear relatively less diverse at the species levelroughly 15 percent of all described species are marine (Reaka-Kudla 1997). Consistent national accounting of marine ecosystems is constrained by a lack of data, but the available indicators are worrying. As of 2002, of 237 domestic stocks managed by the National Marine Fisheries Service (NMFS) whose current status are known, 86 are overfished and overfishing continues for 66 stocks (NMFS 2003). The overfished status of the remaining 695 managed stocks, which are mosdy of lesser commercial importance, is unknown (NMFS 2003). T wo comprehensive national reviews of the state of marine ecosystems, the first in over thirty years, report that marine ecosystems are in crisis (Pew Oceans Commission 2003) and in trouble (U.S. Commission on Ocean Policy 2002. In this chapter, we review the role of the Endangered Species Act in protecting endangered marine species. Although our main focus is on those populations whose ranges fall primarily within the exclusive economic zone, we include both U.S. and foreign listed species in our analyses. EIsewhere (Armsworrh et al., forrhcoming), we review threats and conservation strategies for endangered marine species

Working Seascapes

Marine species are being listed under the Endangered Species Act with increasing frequency and this trend can be expected to continue (Armsworth et al. 2006). The taxonomie focus of marine listings is also diversifying (Armsworth et al. 2006). Despite long-held assumptions that life his tory characteristics of so me marine species render them less vulnerable to extinction, anthropogenie impacts to marine ecosystems have imperiled a growing number of species. In this chapter, we review both the threats endangering marine species and some of the strategies being employed to mitigate those threats. Listing decisions reveal the relative importance of different threats across taxonomie groups and ecosystems (Kappel 2005). Although many threats facing marine organisms are not unique to the seas, their relative importance differs from those faced by terrestrial species. For listed marine, estuarine, and diadromous species the most commonly identified threat is overexploitation (including targeted harvest, bycatch, and indirect effects), which threatens 81 percent of marine, estuarine, and diadromous listed species (Kappel 2005). Habitat degradation ranks second and is listed as a threat to 76 percent of vulnerable marine species, followed by pollution at 61 percent (Kappel 2005). In contrast, Wilcove et al. (2000) found that habitat impacts topped the list of threats to terrestrial and freshwater species, while invasive species and pollution ranked second and third. As for terrestrial species, habitat degradation is the most frequent threat to many estuarine and diadromous species (Kappel 2005). Two other efforts to list marine species at risk of extinction, the IUCN Red List ofThreatened Species (IUCN 2003) and the American Fisheries Society list of fish stocks at risk from extinction (Musick et al. 2000), provide interesting comparisons to the set of species listed as endangered, threatened, or as species of concern under the Endangered Species Act (see Armsworth et al. 2006; NMFS 2002d). Where they intersect in their taxonomic and spatial coverage, the three lists generally agree on the species and subspecies that are most vulnerable. However, each list was created for a distinct purpose and each used different criteria to assess extinction risk. Disparities between lists may therefore reflect gaps in coverage of candidate species, differences in assessment criteria, or different assessment outcomes for particular species

Population Characteristics of the Mangrove Crab Scylla serrata (Decapoda: Portunidae) in Kosrae, Federated States of Micronesia: Effects of Harvest and Implications for Management.

v. ill. 23 cm.QuarterlyApparent declines in abundance of mangrove crabs Scylla serrata (Forsska°l, 1755) in Kosrae, Federated States of Micronesia, have prompted concern regarding long-term persistence of this important cultural and economic resource. To support development of effective management strategies, we gathered basic biological information about mangrove crabs on this island, where S. serrata is the only mangrove crab species present. In particular, we were interested in understanding movement patterns and evaluating spatial variation in population structure. Many population characteristics, including estimated life span, ontogenetic shifts in habitat use, sex-specific allometric relationships, male-biased sex ratios, and evidence for limited (<2 km) alongshore movement, are similar to those reported elsewhere in the range of the species. Therefore, insights from S. serrata populations elsewhere might usefully inform management of the species on Kosrae. Moreover, information reported in this study, for which there is no ambiguity about species identification, has broader relevance. Spatial variation in size structure of the population appears to be driven by variable harvest pressure that reflects distribution of the human population and location of emerging commercial harvest operations. Effective management of mangrove crabs is therefore likely to benefit from application of size-based or sex-based restrictions on harvest and might usefully incorporate spatially explicit strategies, such as partial or complete reserves. Development and implementation of effective management will necessarily depend on cultural as well as scientific information

Viable Salmonid Populations and the Recovery of Evolutionarily Significant Units

Technical Memorandum NMFS series to issue informal scientific and technical publications when complete formal review and editorial processing are not appropriate or feasible due to time constraints. Documents published in this series may be referenced in the scientific and technical literature. The NMFS-NWFSC Technical Memorandum series of the Northwest Fisheries Science Center continues the NMFS-F/NWC series established in 1970 by the Northwes