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Santa Barbara, CA, United States

McKenna M.F.,West Marine | McKenna M.F.,University of California at San Diego | Katz S.L.,Channel Islands National Marine Sanctuary | Condit C.,University of California at San Diego | Walbridge S.,National Center for Ecological Analysis And Synthesis
Coastal Management | Year: 2012

Collisions between ships and whales are an increasing concern for endangered large whale species. After an unusually high number of blue whales (Balaenoptera musculus) were fatally struck in 2007 off the coast of southern California, federal agencies implemented a voluntary conservation program to reduce the likelihood of ship-strikes in the region. This initiative involved seasonal advisory broadcasts requesting vessel operators to voluntarily slow to 10 knots or less when transiting a 75 nm stretch of designated shipping lanes. We monitored ship adherence with those speed advisories using Automatic Identification System data. Daily average speed of cargo and tanker ships and the average speed of individual ship transits before, during, and after the notices were statistically analyzed for changes related to the notices. Whereas a small number of individual ships (1%) traveled significantly slower during the requested periods, speeds were not at or below the recommended 10 knots, nor were daily average speeds reduced during the notices. Voluntary conservation measures are established in a variety of contexts, and may be preferable to regulatory action; in this case, a request to make voluntary changes appeared largely ineffective. Reducing collision risks for whales in this area will require consideration of the various factors that likely explain the lack of adherence when developing an alternative strategy. © 2012 Copyright Taylor and Francis Group, LLC. Source

Katz S.L.,Channel Islands National Marine Sanctuary | Hampton S.E.,National Center for Ecological Analysis And Synthesis | Izmest'eva L.R.,Irkutsk State University | Moore M.V.,Wellesley College
PLoS ONE | Year: 2011

Large-scale climate change is superimposed on interacting patterns of climate variability that fluctuate on numerous temporal and spatial scales-elements of which, such as seasonal timing, may have important impacts on local and regional ecosystem forcing. Lake Baikal in Siberia is not only the world's largest and most biologically diverse lake, but it has exceptionally strong seasonal structure in ecosystem dynamics that may be dramatically affected by fluctuations in seasonal timing. We applied time-frequency analysis to a near-continuous, 58-year record of water temperature from Lake Baikal to examine how seasonality in the lake has fluctuated over the past half century and to infer underlying mechanisms. On decadal scales, the timing of seasonal onset strongly corresponds with deviation in the zonal wind intensity as described by length of day (LOD); on shorter scales, these temperature patterns shift in concert with the El Nino-Southern Oscillation (ENSO). Importantly, the connection between ENSO and Lake Baikal is gated by the cool and warm periods of the Pacific Decadal Oscillation (PDO). Large-scale climatic phenomena affecting Siberia are apparent in Lake Baikal surface water temperature data, dynamics resulting from jet stream and storm track variability in central Asia and across the Northern Hemisphere. Source

News Article
Site: http://news.yahoo.com/energy/

Pollution-free, renewable energy for some 300,000 homes could arrive on the California coast in the next decade if a new wind farm plan can navigate the contentious climate that thus far has derailed all offshore power projects in the state since 1969. Offshore wind development firm Trident Winds wants to put 100 floating wind turbines—tethered to the seafloor with a system of cables—15 miles off the coast from Morro Bay. The array would dwarf the only other offshore wind project in the United States—a five-turbine venture off the coast of Rhode Island, currently under construction. In October, California Gov. Jerry Brown signed a law that compels the state’s utilities to generate half of its electricity from renewables by 2030, and Trident Winds is hopeful the 600-foot-tall turbines could be part of the new energy mix, spinning off Morro Bay by 2025. The ambitious clean energy goals likely mean more offshore wind and wave energy proposals will be on the table for state agencies to consider. If past is prologue though, the road ahead won’t be a breeze. “One hundred turbines covering 40,000 acres is a massive footprint and I know of no other similar proposals offshore,” said Susan Jordan of the California Coastal Protection Network. “Investors see the California coast as a bonanza, but it’s really like no other, and that’s because of the strict laws we have to protect it. We need a statewide policy and guidance to ensure that projects like these move forward in a coherent manner.” In recent years, a handful of small offshore wave energy projects for the Northern California coast have failed to materialize for a variety of reasons—from funding shortfalls, to impact on habitat. Tom Luster, an energy specialist with the California Coastal Commission, says a proposal for a small offshore energy research facility in the California Central Coast is currently wending its way through the approval and funding process. He believes a surge of offshore energy proposals could soon find his desk. “The Coastal Act is built so that it’s pretty flexible,” said Luster. “As projects come up, we might not have specific policies to wind or wave energy, but the main questions are the same: how will projects affect marine life or public access to the shoreline.” RELATED: Wave Power Could Supply Half the U.S. With Cheap Electricity—Here’s Why It Doesn't Eric Markell, one of Trident Wind’s partners, says the proposed site is attractive because of reliable wind resources and existing onshore infrastructure—an existing decommissioned power plant, one of the most recognizable features of the Morro Bay landscape. “The cost of the project is to be determined,” Markell told KQED radio. “Economies of scale will drive down costs—both for the floating infrastructure and the turbines.” The proposed Morro Bay site would float in waters between the Monterey Bay National Marine Sanctuary and the Channel Islands National Marine Sanctuary. But The Sierra Club and local tribe leaders have been working on an initiative to create the Chumash Heritage National Marine Sanctuary—a 140-mile stretch of coastline that includes the proposed Trident site. Andrew Christie of the Sierra Club sees no reason why renewable offshore energy projects couldn’t coexist with protected waters. “NOAA’s approach is similar to ours—we will evaluate the formal project proposal once it’s submitted … and determine if the project’s potential impacts have been adequately analyzed and mitigated or avoided,” he said. “If the Chumash Heritage National Marine Sanctuary has been designated for the area at that time, we’ll also consult with NOAA to assure that harm to sanctuary resources will be avoided.” Globally, offshore wind power is still finding its sea legs. Take England, for example. After five years of public consultation and review, the 76-square-mile Navitus Bay wind farm that would have floated more than 100 turbines off the southern English coast was killed in September. Andy Cummins, Campaigns Director with Surfers Against Sewage, a UK-based nonprofit environmental watchdog agency, worked closely with the Navitus Bay developers to ensure they mitigate any impact on the local recreational resources. Cummins hoped it could have been a precedent-setting case study for offshore wind power. “Ideally, it would have gone in and we could have congratulated them for putting in a responsible renewables program,” said Cummins. “With wind farms more than any other renewables, it comes down to visual impact. This was bordering a wealthy community and a world heritage site. Honestly, as much noise as the engagement of recreational water users made, the thing that stopped it was the visual impact.”

Williams G.D.,Pacific States Marine Fisheries Commission | Andrews K.S.,National Oceanic and Atmospheric Administration | Katz S.L.,Channel Islands National Marine Sanctuary | Moser M.L.,National Oceanic and Atmospheric Administration | And 3 more authors.
Journal of Fish Biology | Year: 2012

The detailed movements of 32 acoustically tagged broadnose sevengill shark Notorynchus cepedianus were documented in and around north-east Pacific Ocean estuarine embayments from 2005 to 2007. Arrangements of passive acoustic receivers allowed analysis of movement at several spatial scales, with sex and size examined as possible factors influencing the pattern and timing of these movements. Notorynchus cepedianus exhibited a distinctly seasonal pattern of estuary use over three consecutive years, entering Willapa Bay in the spring, residing therein for extended periods of time during the summer and dispersing into nearshore coastal habitats and over the continental shelf during the autumn. Notorynchus cepedianus within Willapa Bay showed spatio-temporal patterns of segregation by size and sex, with males and small females using peripheral southern estuary channels early in the season before joining large females, who remained concentrated in central estuary channels for the entire season. Individuals displayed a high degree of fidelity not only to Willapa Bay (63% were documented returning over three consecutive seasons), but also to specific areas within the estuary, showing consistent patterns of site use from year to year. Cross-estuary movement was common during the summer, with most fish also moving into an adjacent estuarine embayment for some extent of time. Most winter and autumn coastal detections of N. cepedianus were made over the continental shelf near Oregon and Washington, U.S.A., but there were also examples of individuals moving into nearshore coastal habitats further south into California, suggesting the feasibility of broad-scale coastal movements to known birthing and nursery grounds for the species. These findings contribute to a better understanding of N. cepedianus movement ecology, which can be used to improve the holistic management of this highly mobile apex predator in regional ecosystems. © 2012. Source

McKenna M.F.,University of California at San Diego | Katz S.L.,Channel Islands National Marine Sanctuary | Wiggins S.M.,University of California at San Diego | Ross D.,Box 101 | Hildebrand J.A.,University of California at San Diego
Journal of the Acoustical Society of America | Year: 2012

Simultaneous long-term monitoring of underwater sound and ship traffic provided an opportunity to study how low-frequency noise correlated with ocean-based commercial shipping trends. Between 2007 and 2010 changes in regional shipping off southern California occurred as a consequence of economic and regulatory events. Underwater average noise levels measured before and during these events showed a net reduction of 12 dB. Statistical models revealed that a reduction of 1 ship transit per day resulted in 1 dB decrease in average noise. This synthesis of maritime traffic statistics with ocean noise monitoring provides an important step in understanding the magnitude and potential effects of chronic noise in marine habitats. © 2012 Acoustical Society of America. Source

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