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Tag: coral reefs

The Radford Becomes a Reef Creating fish habitat

Posted on by david

What was once a 553-foot Navy destroyer has become the East Coast’s largest artificial reef. This summer, as tourism and natural resources officials from Delaware, New Jersey and Maryland looked on, the new “reef,” slowly sunk to the bottom of the Atlantic Ocean. The Del-Jersey- Land reef, (named for the three states involved in the project) took about four hours to make its 138-foot descent.

The USS Arthur W. Radford’s final resting place is roughly 28 miles northeast of the Ocean City inlet, midway between the Indian River and Cape May. The Del-Jersey-Land reef is a cooperative venture between the three states to enhance fisheries habitat through decommissioned and retired ships, and railway and subway cars. 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.

“It’s going to be a huge economic boost for Ocean City,” says Erik Zlokovitz, the artificial reef coordinator for DNR. “It is expected to attract bluefish, sea bass, weakfish, sharks and tuna, and that will attract charter fleets.”

The Radford was commissioned in 1977 and held a crew of more than 300. It patrolled Venezuela, Panama, Argentina, Brazil, Senegal, Oman, Bahrain, the Azores, Nova Scotia, Italy and Turkey. One of its final missions was deployment during Operation Enduring Freedom. The Radford’s homeport was Norfolk, Va.

The ship was named for Admiral Arthur Radford who served in three wars. He was onboard the USS South Carolina during World War I, in the Office of the Chief of Naval Operations during World War II and was Commander in Chief of the U.S. Pacific Fleet at the outbreak of Korean hostilities.

Taking nearly four hours to sink, the USS Radford is the largest ship to become a reef.

Jill Zarend-Kubatko is the Publication Manager in DNR’s Office of Communication.

Coral reefs under threat and losing fish habitat

Posted on by david

FIJI’S coral reef fisheries are under threat from climate change and the threats are greatest for people who will continue to depend on coral reef fisheries.

However, a new book Vulnerability of Tropical Pacific Fisheries and Aquaculture to Climate Change says there are options for sustaining food resources through tuna and aquaculture.

The book also says there will be winners and losers from climate change, and the way Pacific governments react and adapt will be vital.

Dr Johann Bell, a principal fisheries scientist with SPC’s Strategic Engagement, Policy and Planning Facility and one of the book’s three editors, said coral reefs were likely to suffer a lot of damage under the changing climate, and coastal communities in many Pacific island countries and territories would have to find new sources of food.

He said the good news was that Fiji had options – tuna catches were expected to increase in the waters surrounding the country with climate change.

“As coral reefs decline, communities can transfer some of their fishing effort to tuna by using inshore fish aggregating devices,” Dr Bell said.

“Higher rainfall levels are also expected to provide new opportunities to grow freshwater fish in ponds.”

Fiji’s Fisheries Department director Sanaila Naqali says Fiji is already taking steps to counter the expected effects of population growth and climate change on food security.

The book will be published by the Secretariat of the Pacific Community and was launched at the Conference of the Pacific Community in Noumea yesterday by James Batley, the deputy director general of AusAID.

The book was edited by Dr Bell, Johanna Johnson and Alistair Hobday, with the support of the Australian Agency for International Development (AusAID).

It includes contributions from 88 international scientists and took three and a half years to bring together. It also includes summaries for Pacific island countries and territories designed to provide easy access to the main findings for policy makers and other stakeholders.

Dr Bell says the final chapter in the book sets out ways that the Pacific nations can adapt to the new circumstances.Margaret Wise

Solutions range from installing more fish aggregating devices (FADs) to attract tuna closer to shore, to encouraging some communities to grow fish in freshwater ponds; and improving management of mining and forestry industries to prevent sediments and nutrients spoiling fish habitat.

Pacific nations face many pressures to sustain their fish resources and maintain a vital source of food, with climate change posing a fresh challenge.

Dr Bell says like Fiji, losers throughout the Pacific will be those who will continue to depend on coral reef fisheries.

“Higher sea temperatures, ocean acidification, and loss of important habitats like coral reefs, seagrass beds, mangroves and intertidal flats are expected to have a dramatic impact on the fish and shellfish that support many coastal communities.”

“Coral reefs are very likely to suffer a lot of damage under the changing climate, and coastal communities will have to find new sources of food.”

He said communities would need to transfer their fishing effort from coral reef fisheries to the rich tuna resources of the region.

A winner under climate change will be the freshwater fisheries that are so important to the inland population of Papua New Guinea.

The book also outlines the expected improvement of conditions for freshwater pond aquaculture.

But this will not be enough to feed the rapidly increasing populations of Pacific islands, and they will need to rely more on tuna as a source of food.

Dr Jimmie Rodgers, director-general of SPC, says the book is the most comprehensive analysis of the impact of climate change on Pacific fisheries and aquaculture, and the ecosystems that underpin these vital activities.

“The reality is that there will be countries in the Pacific with increased populations and fewer fish to eat. We ignore the book at our peril because it comes up with sound scientific analyses, hard-hitting key messages and policy options,” he said.

“It gives Pacific leaders the opportunity to look 20 years ahead and plan for the future.”

Coral reefs in crisis…..

Posted on by david

Coral reefs in crisis – But they have vast potential

Humans are stopping proper functioning of reefs
April 2011: In an unprecedented collaborative analysis, scientists from 49 nations demonstrated that the ability of reef fish systems to produce goods and services to humanity increases rapidly with the number of species.

COMPLEX: But coral reef systems function best
when there is more biodiversity

However, growing human populations hamper the ability of reefs to function normally, with the most diverse reef fish systems suffer the greatest impairments from stressors triggered by human populations.

‘Coral reefs provide a range of critical goods and services to humanity – everything from nutrient cycling to food production to coast protection to economic revenues through tourism,’ says Camilo Mora at Dalhousie University in Canada and lead researcher of the study. ‘Yet the complex nature and large-scale distribution of coral reefs is challenging scientists to understand if this natural ecosystem will continue working to deliver goods and services given the ongoing loss of biodiversity in coral reefs.

Study involved 2,000 coral reefs worldwide
‘Numerous experiments have shown that biodiversity has positive effects on several ecosystem processes, although the number of species required to ensure the functionality of a given process is fairly low, as many species often have similar ecological roles,’ says Michel Loreau from Canada’s McGill University, a co-author of the study. ‘What remained largely unknown, however, was whether the results of experimental studies reflect what happens in real ecosystems.’

To fill this unknown, 55 researchers, in a two-year study, collected the necessary data to determine whether biodiversity influences the efficiency of reef fish systems to produce biomass, and if so, work out the role of humans in such a linkage.

The team collected demographic data on human populations as well as environmental and biological data on the identity of species, their abundances and body sizes in almost 2,000 coral reef locations worldwide. The data on abundance and body size were used to calculate the cumulative weight of all fishes on each reef (also called standing biomass), which is one of the main services reef fishes provide to humanity through food supply but also a very close proxy for how effectively ecosystems produce biomass.

‘The more biodiversity the better’
‘The results of the study were stunning,’ says Kevin Gaston at Sheffield University. ‘While experimental studies have elucidated that the biomass production of ecosystems stabilises after a certain number of species is reached, this field study demonstrated that the production of biomass in reef fish systems did not saturate with the addition of new species.’

‘This study shows, quite simply, that the more biodiversity, the better,’ says Marah Hardt with OceanInk. ‘The benefits appear limitless, if we allow ecosystems to operate at their full potential.’

Michel Kulbicki of the French Institute for Research and Development said: ‘This strong relationship clearly indicates that species interact in such a way that their combined effect is larger than the addition of their individual parts and that the loss of species can have far-reaching consequences in the functioning of coral reefs.’

The study also demonstrated that standing biomass reduced with increasing human density, although for the same number of people the reduction of biomass was significantly larger in more diverse ecosystems.

‘Curbing human population growth is at the core of finding ultimate solutions for the protection of biodiversity’
‘It’s been usual to expect that diverse ecosystems could lose a few species without it mattering very much because the high redundancy of species should allow the replacement of any species that is lost,’ said Peter F. Sale, assistant director of the Institute for Water, Environment and Health of the United Nations University, who was not involved in the study.

‘The results of this study now suggest that we do not have such insurance and that reef ecosystems are at greater risk from human pressures than we previously thought.’

The negative impact of humanity on reef fish systems can be widespread, as some 75 per cent of the world’s coral reefs are near human settlements and could worsen, as 82 per cent of countries with coral reefs are expected to double their human populations within the next 50 to 100 years.

‘Unfortunately, we find again and again that our global population cannot be sustainably supported without the deterioration of the world’s natural resources and the resulting backlash on human welfare,’ says Mora. ‘Thus, identifying socially and politically acceptable solutions to curb human population growth is at the core of finding ultimate solutions for the protection of biodiversity and the prevention of unnecessary hardship.’

‘This is a critical situation,’ says coauthor Sebastian Ferse from the Leibniz Center of Tropical Marine Ecology. ‘It underlines once again that current management approaches are insufficient to protect marine biodiversity on a large scale, and that holistic approaches combining natural and social systems are needed.’

However it was not all doom and gloom. The study reported that at least 25 per cent of the world’s reefs remain distant from direct human effects. Those reefs are located on small and isolated areas where human habitation is sparse. ‘These few reefs are in stark contrast with degraded sites, and may still be able to act as sources to replenish others. This is a fortunate situation that can buy us some time while we figure out effective solutions to this coral reef crisis.’

artificial fish habitat at fishiding.com

 

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