Summary PROJECT INACTIVE

Groundfish species residing in the California Current ecosystem are the backbone of west coast commercial and recreational fisheries, and juvenile groundfish are key prey items to higher trophic level predators, yet almost nothing is known regarding their vulnerability to increasing OA and hypoxia conditions, either alone, or in the likely scenario of both stressors increasing in concert. Since they have not yet acquired full physiological capacity, early life history stages are expected to be most sensitive to shifts in ocean chemistry. In turn, early life stages are most critical in population dynamics due to the importance of small changes in early survival in modifying recruitment success. Thus, exposure of early life stages to low DO/low pH water may have a disproportionate effect on population dynamics if such exposure increases mortality rates during critical periods of development. This project has three primary objectives: 1. To determine the effect of OA and hypoxia on gravid female rockfish throughout the larval gestation period. 2. To determine the effects of OA and hypoxia on embryo development, larval survival, and metabolic performance of three rockfish species with different life histories. 3. To examine patterns of larval gene expression and enzyme activity levels associated with exposure to OA and hypoxia.

Student Involvement

This project is providing educational opportunities and direct research experience for graduate and undergraduate students at the 3 partner institutions. Students are actively engaged in all components of the lab experiments, field sampling, and genomic analyses. P.I.’s Logan, Sogard and Hamilton and their graduate students are mentoring several UROC students. Students gain valuable research experience in fish husbandry and physiology, genomics, and nearshore oceanography, preparing them for entry into competitive graduate programs. This funding has also supported a group capstone undergraduate laboratory course taught in Spring 2017 at CSUMB. The course teaches students how next generation sequencing techniques can be used to solve environmental problems. Students in this course (~17 undergraduates and graduate students) have learned how to prepare samples for RNAseq and go through the pipeline for how to construct a de novo transcriptome and analyze gene expression data.

Broader Significance

The ability to forecast impacts of OA and hypoxia on rockfish and other groundfish populations will allow for anticipation and possible mitigation of population declines. Understanding and integrating the effects of climate variability on survival into stock assessment models will allow for necessary adjustments to projected fishery yields, ensuring future sustainability. We plan to communicate our results directly with the Pacific Fishery Management Council, which is responsible for setting catch limits, and we will work directly with NOAA stock assessment scientists to incorporate to results into stock assessments, population viability analysis, and fisheries management plans. We anticipate that the primary users of the results will be state and federal resource agencies, especially CA Dept. Fish and Wildlife, NOAA, and the Fishery Management Councils.