This blog is dedicated to bringing you updated information on events, news, ideas, and discussions related to New Hampshire and Northeast Sustainable Marine Fisheries.
Tuesday, December 14, 2010
Curious about NH Fisheries? Check out our new overview page!
Friday, December 10, 2010
Is eating tuna bad for you?
Weighing the health benefits of eating seafood can be a confusing, to say the least. Last week, Consumer Reports produced an article that suggests that pregnant women and young children should avoid eating more than a small amount of tuna. Let's take a look at how they made their recommendation.
In the study, a total of 42 samples (including white or albacore tuna and light or skipjack tuna) were collected and mercury levels were measured by an independent lab. The results found that white tuna had 0.217 to 0.774 parts per million (ppm) of mercury, averaging 0.427 ppm. Light tuna had much lower mercury levels; 0.018 to 0.176 ppm, with an average of 0.071 ppm. None of the samples exceeded the Food and Drug Administrations mercury limit of 1ppm. However, Consumer Reports based its recommendation on the Environmental Protection Agency's reference dose (RfD) for mercury. This reference dose is the recommended limit for daily intake of mercury throughout an individual's lifetime.
Consumer Reports is recommending that at-risk populations (pregnant women and young children) avoid going over this limit so they should not consume more than 2.5 ounces of white (albacore) tuna or 5 ounces of light (skipjack) tuna a day is unsafe for at-risk populations.
Health benefits of eating fish complicate the issue. As many of us know, there are significant health benefits for eating tuna which are high in Omega-3 fatty acids. Experts suggest that individuals in the at-risk population consider focusing on eating fish species that are associated with low mercury thereby still getting the cardiac and developmental benefits of Omega-3's.
All this information can make decision-making about seafood very complicated and you must seek out the best information and make your own choices. Here is a good news article from the medical community from WebMD Health News and a website from the American Heart Association that gives some additional information that you might find useful.
What do you think?
In the study, a total of 42 samples (including white or albacore tuna and light or skipjack tuna) were collected and mercury levels were measured by an independent lab. The results found that white tuna had 0.217 to 0.774 parts per million (ppm) of mercury, averaging 0.427 ppm. Light tuna had much lower mercury levels; 0.018 to 0.176 ppm, with an average of 0.071 ppm. None of the samples exceeded the Food and Drug Administrations mercury limit of 1ppm. However, Consumer Reports based its recommendation on the Environmental Protection Agency's reference dose (RfD) for mercury. This reference dose is the recommended limit for daily intake of mercury throughout an individual's lifetime.
Consumer Reports is recommending that at-risk populations (pregnant women and young children) avoid going over this limit so they should not consume more than 2.5 ounces of white (albacore) tuna or 5 ounces of light (skipjack) tuna a day is unsafe for at-risk populations.
Skipjack tuna is sold as "light tuna" and is relatively low in mercury |
All this information can make decision-making about seafood very complicated and you must seek out the best information and make your own choices. Here is a good news article from the medical community from WebMD Health News and a website from the American Heart Association that gives some additional information that you might find useful.
What do you think?
Tuesday, December 7, 2010
Can small-scale steelhead trout aquaculture operations help local fishermen?
Newcastle, NH – Commercial fishermen came together to discuss an opportunity to raise steelhead trout as an extension to the research UNH Scientists Dr. Hunt Howell and Michael Chambers have been conducting for the past several years.
Gita George, Captain of the Muriel B, holds a steelhead trout grown in a pen off the UNH pier in Newcastle, NH |
Given the current regulatory climate of the fishing industry and the pressures of an economy in a severe recession, steelhead trout may be an opportunity for fishermen to supplement their income while continuing to fish.
The steelhead trout is closely related to the salmon and essentially a saltwater variant of the rainbow trout. They are native to the Pacific Northwest but have been domesticated for more than 150 years. Presently, there are extensive commercial aquaculture industries in Canada and Northern Europe .
The steelhead has done remarkably well off the UNH research pier in Newcastle , N.H . In fact, the fish grow very fast and reached an average size of 6lbs after 6 months. Howell believes the opportunity for N.H. fishermen will be a small-scale, inshore-farm approach, which could produce 8,500 pounds annually in a small 25’ x 25’ x 12’ cage on a single point mooring.
Test market sales this year averaged $4 to $5 per pound retail. Seacoast restaurants and fresh markets were given fish as part of the test marketing. Comments were all positive and the opportunity for a locally produced product was important to their businesses and clientele. Fish are sourced as eggs from Washington and fry (6"-8” or about ½ lb) are raised in a local hatchery and stocked directly into seawater. In April, cages would be stocked at 2,400 fry per cage. When all is said and done you would expect approximately 2,000 market animals (assuming about 15% mortality) to remain, each weighing about 5lbs in November.
Only females are raised; since this species does not occur naturally in this area this avoids any chance of escapees reproducing. Howell adds that the environmental impacts of a small-scale steelhead aquaculture operation would be "miniscule."
Howell is quick to point out that permitting for commercial operations is still an issue but not impossible given that the environmental impacts of small-scale operations are expected to be very small. The process would include a public-hearing process and approval by several agencies. (NHDES, NH Fish and Game, NH Port Authority and USCG).
Friday, December 3, 2010
Dine on a winter delicacy: winter shrimp season is approaching
Starting soon and lasting all winter, Seacoast residents can enjoy an abundance of fresh northern shrimp, a sustainable local resource, and help support the N.H. commercial fishing industry.
Northern shrimp caught in the Gulf of Maine provide fishermen with an alternative to groundfish during the winter months when offshore fishing is more dangerous. Northern shrimp move in close to shore during cold weather, allowing fishermen to stay in safer waters, conserve fuel and save their days-at-sea for groundfishing in better weather conditions.
A growing interest in fresh, local seafood has brought about community supported fishery (CSF) initiatives to the Seacoast and the N.H. Fresh and Local seafood brand. Modeled after community supported agriculture, a CSF is a shore-side community of people collaborating with local fishermen to buy fish or seafood directly for a predetermined length of time. CSF shareholders give the fishermen financial support and then receive a weekly share of seafood caught during the season.
Individuals can join an eight-week shrimp CSF through the Yankee Fisherman's Cooperative. Shareholders will receive five or 10 pounds of fresh shrimp per week (Jan. 9 - Feb. 27) and may choose from several pick-up locations. For more information and to sign up, please visit www.yankeefish.com/shrimp-csf.
In addition, local fresh fish markets and winter farmer's markets near the Seacoast will offer Gulf of Maine shrimp. Organizations such as Seacoast Eat Local offer information about eating locally grown and harvested food at www.seacoasteatlocal.org. To ensure that the shrimp is part of the N.H. Fresh and Local brand, please visit www.nhseafood.com for a list of participating businesses.
Thursday, December 2, 2010
UNH Experts Visit Nova Scotia Aquaculture Operations
Tanks used to raise Halibut at Scotian Halibut Limited |
Professor Hunt Howell, Jonathon Bunker, and I recently traveled to Nova Scotia, Canada, to visit several commercial aquaculture businesses. Our first stop was at Scotian Halibut Limited where Atlantic Halibut are produced from captive brood stock located at their Wood Harbor facility.
After spawning, the eggs are hatched and grown in a large, 5-ton silo tank for several months. Next step is the nursery where they slowly grow to about 30g in one year. Juvenile halibut are then sold to land-based grow-out facilities throughout Canada and the United States.
A portion of the juveniles are sent to Scotian’s grow-out farm in Clarks Harbor. Here they are raised to 5kg or larger and sold to restaurants or used as future brood stock. According to Brian Blanchard, General Manager of Scotian Halibut, Scotian has begun a a new study in which water from the grow-out system circulates through heavily aerated tanks of red macro algae.
The nutrient-rich water, intense lighting, and movement of the algae in the water column allow it to double in size in 3-4 months. The algae acts as nutrient scrubber, absorbing effluents from fish waste before recirculating back through the grow-out system.
After spawning, the eggs are hatched and grown in a large, 5-ton silo tank for several months. Next step is the nursery where they slowly grow to about 30g in one year. Juvenile halibut are then sold to land-based grow-out facilities throughout Canada and the United States.
A portion of the juveniles are sent to Scotian’s grow-out farm in Clarks Harbor. Here they are raised to 5kg or larger and sold to restaurants or used as future brood stock. According to Brian Blanchard, General Manager of Scotian Halibut, Scotian has begun a a new study in which water from the grow-out system circulates through heavily aerated tanks of red macro algae.
The nutrient-rich water, intense lighting, and movement of the algae in the water column allow it to double in size in 3-4 months. The algae acts as nutrient scrubber, absorbing effluents from fish waste before recirculating back through the grow-out system.
The second company visited was Cold Water Fisheries, one of largest producers of Rainbow and Steelhead trout in North America. We toured two of their sea-based farms, one in Liverpool and the other near Pubnico. Each site has approximately 20 floating cages stocked with 30,000 Steelhead trout. Operational Manager Sherman D’Entremont said they use several hatcheries in Nova Scotia and PEI to hatch and raise the trout to 100g before transferring them to the sea cages. The trout are typically grown to 2-3kg and sold mostly to markets in Canada. They are currently producing more than 3500 tons of trout per year
Floating cages in Nova Scotia where steelhead trout are raised. |
Visiting fish farms provides important learning experiences for scientists. It allows us to meet the farming community and learn about their hardships and accomplishments. With this knowledge, we can better prepare research proposals that will help build a strong aquaculture industry.
-Mike Chambers, UNH Cooperative Extension
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