Sea Technology

SEP 2017

The industry's recognized authority for design, engineering and application of equipment and services in the global ocean community

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Page 51 of 68 September 2017 / st 51 & LINEAR For mor building amplifiers to drive reactive loads. Model S16-20 A A 20% duty 35 x 31.5 x 35.5 inches; 985 lbs. isit our 7263 Engineer Rd., San Diego, CA 92111-1493 (858) 571-1111 FAX (858) 571-0188 Copyright 2017 Quality Control of Passive Acoustics Observations." This manual is the 11th in a series of documents that offer guidance for ensuring the highest pos- sible quality of real-time data. Scientists employ passive acous- tics technology to monitor underwater noise and ocean processes. Passive acoustics involves monitoring under- water noise for long periods, which results in large data sets that present a special challenge for passive acoustics telemetry. There are many dozens of acoustic networks around the world, generating hundreds of terabytes of data. Real-time acoustic data QC is critical. Examining Decom Options For Platform Holly When Venoco Inc. declared bank- ruptcy last spring and ceded its off- shore lease, the state of California "in- herited" the 50-year-old Platform Holly off the coast of Santa Barbara. Now the state must decide how to decommis- sion the platform. The 2010 California Marine Resources Legacy Act provides an option for the platform substruc- ture to remain in place as an artificial reef. The decision on platform decom- missioning will eventually need to be made for all the remaining platforms off southern California. To inform the decommissioning process, a team from UC Santa Barbara is partnering with the U.S. Bureau of Ocean Energy Management (BOEM) to determine the biological effects for various platform removal scenarios. The researchers will provide an analysis of the community structure and the productivity of plat- forms compared to surrounding soft- bottom habitats. The research will also examine the changes to habitats that would result from alternative decom- missioning options. River Herring at Near-Historic Lows Atlantic Coast-Wide The Atlantic States Marine Fish- eries Commission's Shad and River Herring Management Board reviewed the results of the 2017 River Herring Assessment Update, which indicates river herring remain depleted and at near-historic lows on a coast-wide basis. The "depleted" determination was used instead of "overfished" and "overfishing" because many factors, not just directed and incidental fishing, are contributing to the low abundance of river herring. Alewife and blueback herring (col- lectively referred to as river herring) are anadromous species, spending the ma- jority of their life at sea and returning to their natal streams to spawn. While at sea, mixing is believed to occur among multiple river-specific stocks, and the incidental catch of river herring in nontargeted ocean fisheries is known to include both immature and mature fish. While status on a coast-wide ba- sis remains unchanged, there are some positive signs of improvement for some river systems, with increasing abun- dance trends for a number of rivers in the Mid-Atlantic throughout the New England region. While abundance in these river systems are still at low lev- els, dam removals and improvements to fish passage have had a positive im- pact on run returns. Since the completion of the 2012 assessment, NOAA Fisheries, in part- nership with the commission, have worked to provide state and local agencies with restoration project fund- ing, leading to dam removals and fish passage improvement projects. ST

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