This dataset is from laboratory experiments that examined the direct effects of projected levels of ocean acidification on the eggs and larvae of walleye pollock.

Annual growth increment patterns observed in the hard parts of many marine organisms are often related to factors in the physical environment, and investigators are increasingly using dendrochronology (tree-ring science) methods to explore these relationships. Dendrochronology techniques were applied to otolith growth increments in 3 flatfish species collected from the eastern Bering Sea: northern rock sole Lepidopsetta polyxystra, yellowfin sole Limanda aspera, and Alaska plaice Pleuronectes quadrituberculatus. Within each species, otoliths were visually crossdated to ensure that the correct calendar year was assigned to each growth increment. Growth-increment widths were measured in each otolith, crossdating was statistically checked, and a master chronology was generated for each species by averaging measurement time series after age-related growth declines had been removed. The 3 final chronologies spanned 18 to 20 yr and were significantly correlated with each other, indicating a high level of growth synchrony among species. Final chronologies were compared to annual and monthly climate variables, and were most strongly related to summertime eastern Bering Sea bottom temperatures.

The importance of high relief structure containing biotic habitat to rockfish and other species remains largely unknown. This data set was created to examine the importance of this habitat for Pacific ocean perch, northern rockfish, and dusky rockfish. These data were derived from four research cruises that occurred between May 2012 and December 2014. During the cruises, video data was recorded of habitat associations, plankton samples were collected, temperature profiles were recorded, and several types of biological samples were taken from trawl captured rockfish. These data will be recorded in several tables in an access database and video files will also be available.

The datasets contain larval size, water temperature, cell cycle data, and classification of larval condition.

Members of the Alaska Fisheries Science Center's (AFSC) Stock Assessment and Multispecies Assessments Program are responsible for determining the condition of fisheries resources in the U.S. Exclusive Economic Zone using data collected by other AFSC scientists and developing strategies for managing those resources. Their research focuses on updating information on population dynamic trends, estimation of biological yields, and management strategies (as presented in annual assessment documents).

Juvenile red and blue king crabs (Paralithodes camtschaticus and P. platypus) were exposed to three pH levels: ambient (pH 8.1), pH 7.8, and pH 7.5 for three weeks. Oxygen consumption and feeding ration were determined immediately after exposure to treatment water and after three weeks exposure. Growth can be calculated from the wet mass observations.

To study the effects of ocean acidification we examined the effects of ocean acidification on the larval stages of the economically important southern Tanner crab, Chionoecetes bairdi. Ovigerous females were reared in one of 3 treatments: control (ambient pH ~8.1), pH 7.8, and pH 7.5 for 2 years. Larvae in year 1 were from oocytes developed in the field whereas larvae in year 2 were from oocytes developed under acidified conditions. Larvae hatched each year, were also exposed to 3 pH treatments to examine starvation-survival, morphology, condition, and calcium/magnesium content. Approximately 300 larvae were stocked in multiple treatments for testing the effect of pH. Hatching success was measured as the total % of larval hatched from a full clutch while duration was the number of days over which hatching occurred. Hatching success did not differ among treatments in 2012 but varied between 46 to 87% in 2013 dependent on pH treatment. Larval mass was highest in pH 7.8 in 2012 and lowest in the control, however in 2013 the highest larval mass was in the control water. There were only small (not significant) changes in magnesium or calcium content among treatments in 2012 however, the reduction in both minerals at higher pH was greater in 2013. There was higher percent carbon and nitrogen contents in pH 7.5 larvae in 2013. The morphology of Tanner crab larval was assessed from 200 larvae stocked in multiple 2 L beakers. There was no effect of treatment on larval morphometrics. In 2012 and 2013, we examined if embryos developed under acidified conditions affected larval morphology by assessing 15 newly hatched larvae from each treatment. There was again no effect of treatment on larval morphometrics. Starvation survival experiments were performed in 1 L sized PVC inserts. In both years larvae from embryos that developed in pH 7.5 water survived about 3 days longer than those that developed in control water. However, in 2012 larvae from embryos that had developed in pH 7.8 water were similar to control larvae whereas in 2013 they were intermediate between the control and pH 7.5 larvae. The overall effects of treatment at the larval stage appeared to be better condition and initial survival at lower pH, however multiple years of treatment led to lower survival.

Annual growth increment patterns observed in the hard parts of many marine organisms are often related to factors in the physical environment, and investigators are increasingly using dendrochronology (tree-ring science) methods to explore these relationships. Dendrochronology techniques were applied to the otolith growth increments of yellowfin sole Limanda aspera to determine the extent to which somatic growth and otolith growth are coupled. Otoliths were visually crossdated to ensure that the correct calendar year was assigned to each growth increment. Growth-increment widths were measured in each otolith, crossdating was statistically checked, and a master chronology was generated by averaging measurement time series after age-related growth declines had been removed. The final chronology spanned 43 yr and was significantly related to Bering Sea bottom temperature and sea surface temperature. The relationship between otolith growth and somatic growth was explored using regression analysis. Population-wide otolith anomalies were found to be significantly related to population-wide anomalies in body size, as indexed by fish weight-length ratios.

To study the effects of ocean acidification we examined the effects of ocean acidification on the embryo stages of the economically important southern Tanner crab, Chionoecetes bairdi. Ovigerous females were reared in one of 3 treatments: control (ambient pH ~8.1), pH 7.8, and pH 7.5 for 2 years. Embryos in year 1 were from oocytes developed in the field whereas embryos in year 2 were from oocytes developed under acidified conditions. Datasets associated with this study include Brooding Duration, Carbonate Chemistry, Embryo Morphology, and Embryo Stages. Embryo stages assessed monthly included detailed developmental stages from the prefuniculus formation through the prehatching stage. Embryo stages were not different among pH treatments. Embryo morphology included egg area, egg diameter, yolk area, yolk diameter, embryo area, eye area, and eye diameter. Each morphological characteristic varied according to pH treatment using a principal component analysis.

Juvenile rockfish were observed amongst coral, sponge, cobble, and gravel habitats. Rockfish utilized coral habitats more than any other, while gravel was the least utilized. Sponge and cobble habitat utilization was intermediate to coral and gravel. Predation of young-of-the-year rockfish by sculpin predators was greatest in gravel habitats and lowest in coral habitats.