StructureSpot

Artificial reefs to boost fish supply

ARTIFICIAL reefs are to be built in local waters to boost fish supplies which have been depleted by over-fishing, pollution, dredging and dumping.

The Agriculture and Fisheries Department yesterday announced it was investigating sites for the reefs and had received $1.6 million from the Royal Hong Kong Jockey Club to start the project.
Reefs provide nursing and feeding grounds for all sorts of marine life including larger fish sold in local markets.
Fisheries officer David Cook said it was hoped local stocks would be boosted and the diversity of marine life in Hong Kong would increase with the reefs.
”We see that there’s a need to provide some level of redress for the perceived damage that’s occurring to the marine environment,” he said.
Fishermen and environmentalists have stepped up campaigns in the past year to call attention to the destruction caused by dredging and dumping for the airport projects. Silt is stirred up that can smother corals and drive away fish.
But overfishing is also a concern and Mr Cook said fishing around the reefs would be restricted.
He said fishermen in Malaysia and Thailand had abided by fishing restrictions around artificial reefs in their waters because they increased fish production by up to 400 times in some cases.
It was impossible to say how much impact the scheme would have on Hong Kong fisheries as this would be proportional to the scale of the project, he said.
But fish stocks are expected to increase when the first reefs are set up in soon-to-be-established marine parks where legislation already restricts fishing, he said. The first park is expected to be declared later this year, probably in the eastern waters.
But the declaration of the parks is likely to be slow and cover only a limited area, and any large-scale setting up of artificial reefs will require about $65 million.
The Jockey Club’s $1.6 million contribution will be used towards setting set up the first few reefs and determine the best reef sites.
The programme is separate from trials being carried out on an artificial reef made from coal ash in Hoi Ha Wan, which is still underway. Until results are available on its safety, the reefs will be made from more expensive reinforced concrete.
It is also hoped to use sunken ships, possibly some of the hundreds of vessels destroyed by the Marine Department each year, as these can provide the solid surface and nooks and crannies needed for a successful reef.
Hong Kong’s natural coral reefs are in the eastern waters and many have been damaged by dredging and pollution and by a mysterious water current last month that killed everything in a 40-square-kilometre area.
Most of the rest of the sea bottom is flat and soft, and the reefs will provide a place for marine organisms to grow, providing food for larger animals.By KATHY GRIFFIN
Mr Cook said. Dozens of unique habitat models at fishiding.com

Artifical Products grow fish

First Coast may need to help bolster key industry – fishing

 First Coast anglers see fishing spots disappearing so quickly they say it’s time to create new fishing grounds to bolster an industry that the state says brings half a billion dollars into the local economy every year.
Scott Shine, a member of the Jacksonville Waterways Commission, said he is looking into ways to add more access to fishing in North Florida before the economic impact does permanent damage to the recreational fishing industry.
A Waterways Commission subcommittee has been formed to examine adding artificial reefs just offshore and in the St. Johns River.
See the dozens of unique artificial fish habitat models, fish attractors and fish cover used at fishiding.com, the leader in proven science based, fish protection.
The federal government has closed several offshore fishing spots in recent years because of depleted fish stocks. There are also large tracts of water that have been placed off limits to vessels around military installations for security reasons.
“While we grow and while we’re seeking opportunities for tourism, we’re not growing our access to waterways on the same level that we’re experiencing in the growth in population,” Shine said.
RestrictionsThe recent restrictions cover hundreds of miles of ocean off the Southeast coast of the United States. Along the First Coast, those restrictions are hampering an industry that generates about $556 million a year for Northeast Florida, according to a report Shine drafted in January based on a 2010 Florida Fish and Wildlife Conservation analysis.
Shine based his figures on the North Florida share of fishing licenses sold in the state along with other factors, such as fishing industry tracking data the state agency used to develop estimates.
Recent federal regulations restricting offshore catches of grouper, red snapper and other fish are already beginning to take their toll on the area recreational fishing industry.
“We’ve been losing ground,” said Vic Tison, who runs a charter boat fishing service and is chairman of the North Florida Chapter of the Recreational Fishing Alliance. “We’re getting less and less areas to fish. Where’s that going to leave us?”
Adding to the frustration for anglers is a restricted zone instituted around Mayport Naval Station last year.
With little public notice, the U.S. Army Corps of Engineers added a 380-foot no-vessel zone on a 2½-mile stretch of water surrounding the base.
Tison said it has already blocked many of his charter excursions that used to sail near the base.
Roy Crabtree, the Southeast regional administrator for National Oceanic and Atmospheric Administration Fisheries, said the agency takes into account the economic impact when implementing restrictions. In addition, Crabtree said recreational and commercial fishing interests were represented on the panel that made the decisions.
SolutionsWhile Shine concedes there is little sports anglers can do about the restrictions, he thinks the problem can be mitigated by creating new areas for fishing.
He said creating artificial reefs within 3 miles of shore would put those waters under state jurisdiction, cutting the federal government out of the equation. In addition, Shine wants artificial reefs to be sunk in the St. Johns River near the Mill Cove area in order to offset the restricted zones around the Mayport base and Blount Island.
“It increases access to fishing opportunities,” Shine said. “The federal government is drawing boxes on a map that are shutting down fishing and access in those areas.”
Crabtree said Shine’s proposal could provide some increased access in the face of the federal restrictions.
“If they were to put artificial reefs in state waters over there, that may provide access in fishing for anglers of a variety of species,” he said.
Tison acknowledged Shine’s proposals could keep the recreational fishing economy stable.
“It’s very important,” he said. “We’re getting less and less areas to fish continually. … Anytime you put a rock down or a structure down in the water, it’s going to create fishing habitat, and that gives the anglers more areas to fish.”

By Matt Dixon 
Morris News Service

Artificial Reefs and Seagrass

Article of the Week 2 – Artificial Reefs

Posted by laymanc

Coastal ecosystems may be the most anthropogenically-altered on the planet.  Habitat loss, over-fishing, nutrient loading, and many other impacts have fundamentally changed the structure and function of these systems.  Many of these impacts operate over rather large spatial scales (think global warming or the loss of migratory fishes); however, most marine ecology actually is conducted at the smallest scales.  Foundational ecological theory took root in experiments conducted in coastal intertidal zones, often at scales of a meter or less.  But ecologists now are challenged to develop approaches that better fit the large scales at which human impacts are altering coastal ecosystems.

In terrestrial systems, “landscape” ecology is a well-developed sub-discipline.  Yet tenets of this are rarely applied in marine systems.  This study was among the first to do so and to use manipulative approaches as we constructed a series of artificial reefs in the Bight and specifically chose locations within different “seascape” contexts.  This allowed us to examine the importance of relatively large-scale (hundreds of meters) features in determining local fish community structure.  That is, instead of just examining small-scale aspects of the reef itself, we included much larger scale factors (such as seagrass cover) and used these to explain the makeup of fish communities.

See the dozens of unique artificial fish habitat models, fish attractors and fish cover used at fishiding.com, the leader in  science based, proven, fish protection.

We found that the amount of seagrass at large spatial scales was one of the most important features determining to number and identity of fishes using these artificial reefs.  Specifically, reefs that had more seagrass within 100 m had more fishes.  This may be explained by the fact that many reef species like grunts, snapper and lobster that use reefs during the day migrate out into the surrounding seagrass at night to feed.  However, not all species of fish responded to the amount of seagrass in the same way.  For example, the number of white grunts increased with more seagrass cover within the seascape, but the number of French grunts decreased.  This means that changes in the cover of seagrass within large areas surrounding reefs can affect both the number and types of fishes using reefs.  Human activities that cause even subtle changes to seagrass habitat can impact reef fish communities even before the complete loss of seagrass habitat.

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