|Concrete pilings support oysters better than other materials.|
Sunday, May 18, 2014
This article is excerpted from an original article in the Fish site that can be found here.
US - Filter-feeding organisms such as oysters, mussels and barnacles improve water quality, with large colonies filtering vast amounts of water every day. These natural habitats are often destroyed by manmade structures on shorelines because dock owners may use materials that actively discourage oyster colonization for aesthetic reasons.
Researchers in the US have now quantified this effect for the first time and are calling for incentives for residents to use materials that encourage these filter-feeding organisms to colonize.
Craig Layman, then at Florida International University, US, and his colleagues looked at oyster populations in the Loxahatchee River and estuary, on the southeast Atlantic coast of Florida. Manmade development has greatly disturbed shoreline habitats here, but the river still supports ~60,000 sq. m of natural subtidal oyster reefs as well as an additional 24,000 sq. m of oyster restoration reefs that were constructed in the river in 2010.
“We found that filter-feeding organisms that colonized dock pilings have about 30 per cent of the filtration capacity of the entire 60,000 sq. m of natural reef habitat,” Layman told environmentalresearchweb.
“Perhaps even more surprising is that dock piling filtration is roughly double the estimated filtration capacity of the organisms supported by the large-scale oyster restoration reefs.”
Layman believes that by encouraging dock owners to use more oyster-friendly materials, this figure could be increased even further. The study found that concrete pilings supported 68 per cent of total filtration, despite accounting for only seven per cent of all pilings. Other pilings are made from wood, PVC pipe filled with concrete or wood wrapped in a high-density polyethylene material (pile wrap). Pile wrap was the most common dock piling type, making up 69 per cent of the river’s dock pilings, yet these pilings supported only 10% of all filtration.
“Introducing a tax credit for concrete pilings, which are the most expensive type of piling but the most oyster-friendly, would encourage home owners to use this material,” said Layman.
“Substituting pile wrap pilings for concrete pilings could even negate the need for expensive projects such as the building of artificial reefs. We are not justifying the conversion of natural shorelines to manmade structures, but our research has shown that, if development takes place, a careful choice of materials can minimize the effect on populations of filter-feeding organisms.”
Thursday, May 15, 2014
Sunday, May 4, 2014
On Thursday night Curt Felix, vice chair of the Wellfleet Comprehensive Wastewater Planning Committee spoke as part of the new England Aquarium lecture series. He discussed oyster restoration and the experience Wellfleet has had with their oyster propagation zone. (Note that Mass Oyster has supported this project financially and with recycled shell.) His fascinating discussion enthralled the 150 people assembled in the IMAX theatre for the event. The lecture featured some interesting video clips, photos of the restoration progress as well as lots of data. Below are some of the high points from his talk.
|Curt Felix Speaking at the New England Aquarium|
Oyster habitat is a threatened environment with 85% of oyster habitat lost worldwide and 95% of Massachusetts' oyster reef is now gone.
Interestingly in the early 1600 oysters were so abundant that they intimidated explorers. The famous French explorer Samuel de Champlain who founded Quebec traveled throughout New England and maritime Canada. According to his ship’s log he did not go into Wellfleet Harbor in the 1602 because he saw so much oyster reef sticking out of the water he felt is unsafe to proceed.
|Explorer Champlain stayed clear of the billions of oysters forming oyster reefs in Wellfleet harbor for the safety of his ship.|
An oyster filters 50 gallons of water per day. They are the water quality engineers of the estuarine ecosystem that have 3 different ways of removing nitrogen: 1) an oyster assimilates 0.375 grams per year into its meat and shell; 2) Oyster pseudofeces creates a bacterial process that eliminates 0.35 grams directly to the atmosphere; 3) another .75 grams is taken up by the 100’s of other creatures that are attracted to an oyster reef.
In other areas around the country restoration efforts are getting some success. Maryland committed $8 million to oyster restoration in 2014 as part of an ongoing program.. Through this program oyster diseases have fallen to the lowest levels ever recorded. They also have had the highest spat survival rates since 1985 and increased the estuary’s biomass over 44%..
n the Wellfleet Study area they have counted in excess of 4 million oysters in 3 years and an estimated 40 million throughout the harbor. These oysters filter an estimated 30 billion gallons of water per day. In the study site they have documented a 70% reduction in Nitrogen. Samples are taken on the outgoing tide and the nitrogen levels now measure in the excellent range according to EPA standards. So the water flowing out of the study area is a positive influence on Wellfleet Harbor overall. With this the Ulva or sea lettuce has disappeared in the propagation zone. Ulva is a classic indicator of excess nitrogen.
|Lettuce looking Ulva is usually a sign of excess nitrogen|
Chlorophyl levels have also dropped. This is good for eelgrass, which needs lots of light. Eelgrass is an important habitat for fish and scallops.
With more nooks and crannies to hide in they have seen a steady increase in biodiversity. Some notable trends include the return of Menhaden or “pogeys.” In 2013 there were over 50 rare diamondback terrapins regularly feeding at the site.
|Diamond Back Terrapin|
Looking at water quality on the Cape a number of town’s have challenges that in aggregate could require $4-6 billion to try to fix with conventional sewers. With town budgets already tapped heavily and the reasonable cost of restoring oysters, it is natural for the towns to be examining this option more closely. Felix emphasized that oysters would not be a quick fix and that it will take a sustained effort to build experience and significant oyster populations but that water quality could be improved within years rather than decades and reduce significantly, the overall cost of meeting estuary water quality requirements.
Saturday, May 3, 2014
North Carolina Sea Grant Extension Program
Marine Aquaculture Extension Specialist
Morehead City, NC
Develop extension programming related to marine aquaculture (shellfish and finfish) at the local, state and regional levels, so as to advance a safe, secure and sustainable supply of marine aquaculture products to meet increasing public seafood demand.
Support new market initiatives including business development and enhancing existing business profitability, while conserving natural resources and strengthening coastal communities.
|NC State supports a Sea Grant Program|
Initiate and nurture partnerships with federal, state and local agencies to develop a coordinated approach to serving these specific clientele groups and the general public. Increase the demand and identify new market channels for North Carolina marine aquaculture products.
Details and application instructions: https://jobs.ncsu.edu/
Thursday, May 1, 2014
After Oyster Restoration and Oyster Propagation- Oyster Consumption- What Wines Pair Well with Oysters?
According to wine aficionado Harvey Steiman, here are his five recommendations.
You can see his full blog post here.
|Wine and Oysters- A Delightful Pairing|
First, Chateau Ste. Michelle Sauvignon Blanc Columbia Valley 2013: Its freshness and grapefruit flavor notes register brilliantly with the oyster's mineral notes. A mouthwatering finish calls for another oyster, and another sip, and …
Second, Sebastiani Sauvignon Blanc Sonoma County 2013: Open-textured, its grapefruit notes come through on the refreshingly balanced finish and clean the palate for more.
Third, King Estate Pinot Gris Oregon Signature Collection 2012: Fresh, bright flavors of quince and lemon pop through the creamy oysters, completing the picture nicely.
Fourth, Van Duzer Pinot Gris Willamette Valley 2013: Dry and steely, a balance that feels right, a flavorsome, savory wine that adds a refreshing element to the mildly briny oysters.
Fifth, Kenwood Pinot Gris Russian River Valley 2012: This plus the oyster creates a flavor riot in the mouth, a vivid match that sings of creamy pineapple, guava and lime flavors without overpowering the oyster's character.
For the record, all of those wines made the consensus top 10 except for King Estate Pinot Gris. The others were Acrobat Pinot Gris 2012 and Foris Pinot Blanc 2012 from Oregon, Geyser Peak Sauvignon Blanc 2013, Kenwood Sauvignon Blanc 2013, and Revolution Wines Chenin Blanc 2013 from California, and Lost River Pinot Gris 2013 from Washington.
You can see his full blog post here.