scholarly journals Using integrated, ecosystem-level management to address intensifying ocean acidification and hypoxia in the California Current large marine ecosystem

Elem Sci Anth ◽  
2017 ◽  
Vol 5 ◽  
Author(s):  
Terrie Klinger ◽  
Elizabeth A. Chornesky ◽  
Elizabeth A. Whiteman ◽  
Francis Chan ◽  
John L. Largier ◽  
...  

Ocean acidification is intensifying and hypoxia is projected to expand in the California Current large marine ecosystem as a result of processes associated with the global emission of CO2. Observed changes in the California Current outpace those in many other areas of the ocean, underscoring the pressing need to adopt management approaches that can accommodate uncertainty and the complicated dynamics forced by accelerating change. We argue that changes occurring in the California Current large marine ecosystem provide opportunities and incentives to adopt an integrated, systems-level approach to resource management to preserve existing ecosystem services and forestall abrupt change. Practical options already exist to maximize the benefits of management actions and ameliorate impending change in the California Current, for instance, adding ocean acidification and hypoxia to design criteria for marine protected areas, including consideration of ocean acidification and hypoxia in fisheries management decisions, and fully enforcing existing laws and regulations that govern water quality and land use and development.

2013 ◽  
Vol 10 (7) ◽  
pp. 11825-11856 ◽  
Author(s):  
G. E. Hofmann ◽  
T. G. Evans ◽  
M. W. Kelly ◽  
J. L. Padilla-Gamiño ◽  
C. A. Blanchette ◽  
...  

Abstract. The California Current Large Marine Ecosystem (CCLME), a temperate marine region dominated by episodic upwelling, is predicted to experience rapid environmental change in the future due to ocean acidification. Aragonite saturation state within the California Current System is predicted to decrease in the future, with near-permanent undersaturation conditions expected by the year 2050. Thus, the CCLME is a critical region to study due to the rapid rate of environmental change that resident organisms will experience and because of the economic and societal value of this coastal region. Recent efforts by a research consortium – the Ocean Margin Ecosystems Group for Acidification Studies (OMEGAS) – has begun to characterize a portion of the CCLME; both describing the mosaic of pH in coastal waters and examining the responses of key calcification-dependent benthic marine organisms to natural variation in pH and to changes in carbonate chemistry that are expected in the coming decades. In this review, we present the OMEGAS strategy of co-locating sensors and oceanographic observations with biological studies on benthic marine invertebrates, specifically measurements of functional traits such as calcification-related processes and genetic variation in populations that are locally adapted to conditions in a particular region of the coast. Highlighted in this contribution are (1) the OMEGAS sensor network that spans the west coast of the US from central Oregon to southern California, (2) initial findings of the carbonate chemistry amongst the OMEGAS study sites, (3) an overview of the biological data that describes the acclimatization and the adaptation capacity of key benthic marine invertebrates within the CCLME.


2014 ◽  
Vol 11 (4) ◽  
pp. 1053-1064 ◽  
Author(s):  
G. E. Hofmann ◽  
T. G. Evans ◽  
M. W. Kelly ◽  
J. L. Padilla-Gamiño ◽  
C. A. Blanchette ◽  
...  

Abstract. The California Current Large Marine Ecosystem (CCLME), a temperate marine region dominated by episodic upwelling, is predicted to experience rapid environmental change in the future due to ocean acidification. The aragonite saturation state within the California Current System is predicted to decrease in the future with near-permanent undersaturation conditions expected by the year 2050. Thus, the CCLME is a critical region to study due to the rapid rate of environmental change that resident organisms will experience and because of the economic and societal value of this coastal region. Recent efforts by a research consortium – the Ocean Margin Ecosystems Group for Acidification Studies (OMEGAS) – has begun to characterize a portion of the CCLME; both describing the spatial mosaic of pH in coastal waters and examining the responses of key calcification-dependent benthic marine organisms to natural variation in pH and to changes in carbonate chemistry that are expected in the coming decades. In this review, we present the OMEGAS strategy of co-locating sensors and oceanographic observations with biological studies on benthic marine invertebrates, specifically measurements of functional traits such as calcification-related processes and genetic variation in populations that are locally adapted to conditions in a particular region of the coast. Highlighted in this contribution are (1) the OMEGAS sensor network that spans the west coast of the US from central Oregon to southern California, (2) initial findings of the carbonate chemistry amongst the OMEGAS study sites, and (3) an overview of the biological data that describes the acclimatization and the adaptation capacity of key benthic marine invertebrates within the CCLME.


2015 ◽  
Vol 72 (7) ◽  
pp. 2128-2138 ◽  
Author(s):  
Hannes Baumann ◽  
R. J. D. Wells ◽  
Jay R. Rooker ◽  
Saijin Zhang ◽  
Zofia Baumann ◽  
...  

Abstract Juvenile Pacific bluefin tuna (PBT, Thunnus orientalis) are known to migrate from western Pacific spawning grounds to their eastern Pacific nursery and feeding grounds in the California Current Large Marine Ecosystem (CCLME), but the timing, durations, and fraction of the population that makes these migrations need to be better understood for improved management. To complement recent work focused on stable isotope and radiotracer approaches (“tracer toolbox”; Madigan et al., 2014) we explored the suitability of combining longitudinal analyses of otolith microstructure and trace elemental composition in age ∼1–2 PBT (n = 24, 66–76 cm curved fork length) for inferring the arrival of individuals in the CCLME. Element:Ca ratios in transverse otolith sections (9–12 rows, triplicate ablations from primordium to edge, ø50 μm) were quantified for eight elements: Li, Mg, Mn, Co, Cu, Zn, Sr, and Ba, which was followed by microstructure analysis to provide age estimates corresponding to each ablation spot. Age estimates from otoliths ranged from 328 to 498 d post-hatch. The combined elemental signatures of four elements (Ba, Mg, Co, Cu) showed a significant increase at the otolith edge in approximately half of the individuals (30–60 d before catch). Given the different oceanographic properties of oligotrophic open Pacific vs. high nutrient, upwelling CCLME waters, this signal is consistent with the entry of the fish into the CCLME, which was estimated to occur primarily in July after a transoceanic migration of ∼1.5–2.0 months. Our approach comprises a useful addition to the available tracer toolbox and can provide additional and complementary understanding of trans-Pacific migration patterns in PBT.


PLoS ONE ◽  
2019 ◽  
Vol 14 (7) ◽  
pp. e0217711 ◽  
Author(s):  
Lisa G. Crozier ◽  
Michelle M. McClure ◽  
Tim Beechie ◽  
Steven J. Bograd ◽  
David A. Boughton ◽  
...  

Author(s):  
Zachary Gold ◽  
Emily Curd ◽  
Kelly Goodwin ◽  
Emma Choi ◽  
Benjamin Frable ◽  
...  

DNA metabarcoding is an important tool for molecular ecology. However, its effectiveness hinges on the quality of reference sequence databases and classification parameters employed. Here we evaluate the performance of MiFish 12S taxonomic assignments using a case study of California Current Large Marine Ecosystem fishes to determine best practices for metabarcoding. Specifically, we use a taxonomy cross-validation by identity framework to compare classification performance between a global database comprised of all available sequences and a curated database that only includes sequences of fishes from the California Current Large Marine Ecosystem. We demonstrate that the curated, regional database provides higher assignment accuracy than the comprehensive global database. We also document a tradeoff between accuracy and misclassification across a range of taxonomic cutoff scores, highlighting the importance of parameter selection for taxonomic classification. Furthermore, we compared assignment accuracy with and without the inclusion of additionally generated reference sequences. To this end, we sequenced tissue from 605 species using the MiFish 12S primers, adding 253 species to GenBank’s existing 550 California Current Large Marine Ecosystem fish sequences. We then compared species and reads identified from seawater environmental DNA samples using global databases with and without our generated references, and the regional database. The addition of new references allowed for the identification of 16 native taxa and 17.0% of total reads from eDNA samples, including species with vast ecological and economic value. Together these results demonstrate the importance of comprehensive and curated reference databases for effective metabarcoding and the need for locus-specific validation efforts.


2020 ◽  
Vol 250 ◽  
pp. 108743
Author(s):  
Thomas P. Good ◽  
Jameal F. Samhouri ◽  
Blake E. Feist ◽  
Chris Wilcox ◽  
Jaime Jahncke

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