Marine Resources – April
Oyster Aquaculture Can Limit Spread of Disease
A study initiated by Dr. Ryan Carnegie of the Virginia Institute of Marine Science has found that oyster aquaculture operations can limit the spread of disease among wild populations of oysters, contrary to long-held beliefs that diseases are often spread from farmed to wild populations. The study is based on mathematical modeling using data from the Gulf of Mexico through the Atlantic.
Diseases are a primary limiting factor in wild oyster populations. Dermo, for example, is caused by a single-celled parasite occurring naturally in the environment and proliferates in the tissue of host oysters, which spread the parasite to other oysters when they die and decay. It takes two to three years for the parasite to kill the oysters. As long as the oysters are held on farms long enough to filter disease-causing parasites from the water, but not so long that parasites develop and spread to wild oysters nearby, aquaculture operations can reduce disease in wild populations.
Spitzer Trust Grant to Expand
EESI’s Work on Resilience
The New York-based Bernard and Anne Spitzer Charitable Trust has awarded a $300,000 grant to the Environmental and Energy Study Institute (EESI) to showcase resilience as a major component of climate change adaptation in federal policy, with a focus on coastal communities and nature-based solutions.
The 2017 disaster season was the costliest on record, with more than $300 billion in damage.
Wealth of Potential for
Aquaculture in Caribbean
A team led by researchers at UC Santa Barbara’s Bren School of Environmental Science & Management and the Marine Science Institute (MSI) looked at the feasibility of aquaculture in the Caribbean, focusing on offshore mariculture, which offers a promising alternative to land-based and coastal aquaculture, where space is limited and environmental impacts are often high.
Even under conservative estimates, the region could produce more than 34 million metric tons of seafood per year, larger than two orders of magnitude of the region’s current seafood production.
eDNA for More Efficient
Alaska Salmon Count
Researchers from the University of Alaska Southeast, Auke Bay Laboratories, Oregon State University, the U.K. and China have found that salmon DNA collected in water samples from Auke Creek can be used to infer the number of salmon passing upstream to spawn.
Environmental DNA (eDNA) can be collected from water samples that are then filtered and probed using molecular genetic techniques to quantify the amount of DNA belonging to each salmon species.
Salmon entering Auke Creek were counted by hand. Water samples were then collected from Auke Creek, and the eDNA from coho and sockeye salmon in water samples was quantified to see whether it predicted the number of hand-counted salmon. Simple models combining eDNA counts and stream flow accurately detected pulses in coho and sockeye salmon as they migrated upstream to spawn.
eDNA collection from water samples may provide a cheap means to track the abundance of salmon returning to spawn in creeks where other survey methods are logistically challenging or prohibitively expensive. Future efforts will expand location testing.
Oceana Investigation Pins Countries, Vessel to IUU List
Following an investigation by Oceana using the Global Fishing Watch mapping platform, the South Pacific Regional Fisheries Management Organization (SPRFMO) decided to keep the fish factory vessel Damanzaihao (now named Vladivostok 2000) on its list of illegal, unreported and unregulated (IUU) fishing vessels and issued warnings to China, Panama and Cook Islands against providing assistance to the vessel. The SPRFMO’s Compliance and Technical Committee found that these three countries were not in compliance with conservation and management measures to combat IUU fishing and issued them a “priority non-compliance” status.
Battery Parts from Plastic Bags
Researchers have a new method to convert plastic bags, often ending up as ocean waste, into carbon chips that could be used as anodes for lithium-ion batteries.
Vilas Pol and colleagues immersed polyethylene plastic bags in sulfuric acid and sealed them in a solvothermal reactor, which heated the sample to just below polyethylene’s melting temperature. This caused sulfonic acid groups to be added to the polyethylene carbon-carbon backbone so that the plastic could be heated to a much higher temperature without vaporizing into hazardous gases. They removed the sulfonated polyethylene from the reactor and heated it in a furnace in an inert atmosphere to produce pure carbon, then ground into a black powder to make anodes for lithium-ion batteries, with comparable performance to commercial batteries.
Mariners’ Museum Library
Houses Lighthouse Collection
The Mariners’ Museum and Park was chosen as the new caretaker of The United States Lighthouse Society Wayne Wheeler Library collection of books, journals and lighthouse reports, which holds 4,000 volumes. The Mariners’ Museum Library holds the largest maritime history collection in the Western Hemisphere.