• Genetic Switches Help Fish Adjust to Fresh and Salty Water
• Fish populations drop in North Atlantic
• Philadelphia Scientist Solves Evolutionary Mystery of Land Plants
• AIDS in fishing communities: a serious problem, frequently overlooked
• Leading veterinary experts of 28 countries call for more vigorous bird flu control
• Aquatic Resources and Fisheries
• News from the FAO Regional Offices
  

February 14, 2005

UC Davis researchers have discovered two key signals that tell fish how to handle the stress of changing concentrations of salt as they swim through different waters.

Not many fish can travel between saltwater and freshwater. To maintain the right internal salt level, their gills must pump up salt from freshwater but excrete it in the ocean.

"Fish that can survive both environments are able to resist many kinds of stress," said Dietmar Kueltz, an assistant professor of animal science.

Kueltz's team wants to understand the chain of signals that control the stress response in these fish. They experimented with tilapia, moving the fish directly from a freshwater tank to one holding seawater. They observed a rapid increase in the levels of two transcription factors: proteins that flip specific genes on and off in the tilapia's gills.

Now, Kueltz says, his team will use its findings to identify the next steps in the pathway of stress signals.

"When you find transcription factors regulated by stress, you have a tool in your hands that you can use to search for genes" further down the pathway, he explained. "This work will help us understand why some fish tolerate stress well," said Kueltz. Such fish might be better able to survive other stresses, "like climate change or exposure to toxins from agricultural runoff."

Kueltz's work was published in the Jan. 10 online edition of the Proceedings of the National Academy of Sciences. His work was funded by the National Science Foundation.

Miami, FL, Feb. 11 (UPI) -- Predatory fish populations in the North Atlantic have decreased 90 percent in the past 40 to 50 years, Canadian researchers found.

Sharks are particularly vulnerable to extinction because they grow slowly and produce few young, researchers from Dalhousie University in Nova Scotia. Although species such as cod and billfish produce many young, few eggs survive to maturity, they said.

Sharks and billfish frequently are caught with targeted food fish, such as swordfish and tuna.

The researchers analyzed mostly North Atlantic cod communities and found some schooling areas showed a 90 percent to 99 percent depletion of cod population.

Closures in certain areas helped the recovery of haddock and other species, but not cod. The researchers suggested reducing fishing mortality of certain sensitive species, reducing bycatch, using spatial closures to initiate recovery and establishing permanently closed marine ecosystems in key areas such as spawning grounds.

The study was funded by the Pew Institute for Ocean Science and the Census of Marine Life.

"The management actions taken today will determine whether we enjoy biologically diverse and economically profitable fish communities 20 or 50 years from now," said Ellen Pikitch, the institute's executive director.

The Academy of Natural Sciences' Botanist Debunks Long Held Theories

A botanist with The Academy of Natural Sciences has succeeded in identifying the ancestor of the first plants to grow on land, in the process debunking two generally held theories and solving a mystery that had confounded scientists for more than a century, it was announced today.

The finding, published in this week's issue of the journal Science, has broad implications for the advancement of plant science. Some 470 million years ago there were no plants living on land anywhere on Earth. Plants lived only in water. Today there are more plants living on land than exist in all the world's oceans and lakes, and plants are a vital food source for the world's population.

Using the relatively new technique of gene sequencing to examine the DNA of ancient land and water-based plants, Dr. Richard McCourt, Associate Curator of Botany at The Academy of Natural Sciences, and his colleagues determined that the earliest terrestrial plants shared a common ancestor with a common group of green algae called stoneworts. They also put to rest the theory that plants made the transition to land from oceans; rather, they invaded land from freshwaters such as streams and ponds.

"In just the last decade we've seen the development techniques to study gene sequences that made our study possible," said McCourt, who along with colleagues at the University of Maryland publishing their research in this week's Science with the title, "The Closest Living Relatives of Land Plants."

When McCourt began studying pond scum 20 years ago, he didn't really expect that his research would help solve one of the long-standing conundrums of evolutionary biology: What were the aquatic ancestors of the first plants to invade land?

To answer that question, McCourt and the group spent several years sequencing several genes in a wide variety of land plants and aquatic green algae. And the answer is surprising in several ways, said McCourt. Of the thousands of species of green algae, commonly known as pond scum, in the world, it turns out the closest relative of land plants is a relatively complicated group of algae commonly called stoneworts. Growing up to several feet in length, the slender, threadlike algae have whorls of branches a few inches in length. Academy They are called stoneworts, said McCourt, because many of them are encrusted with lime, which may offer some protection from grazing animals. In contrast to many other green algae, which are single cells or relatively simple colonies or chains of cells strung together, the stoneworts grow upright with branches off a central strand of what are called "giant cells." These giant central cells have many nuclei and are several times the width of a human hair wide and an inch or more in length.

"The cells are so large that they are popular among plant physiologists because they're easy to manipulate," said McCourt. Other relatively advanced features of stoneworts include sexual reproduction using eggs and sperm, biochemical processes that are more similar to land plants than other green algae, and an early stage of development that looks like the early growth stage of a moss plant, one of the simpler types of land plants.

"These things have an extensive fossil record going back some 450 million years, which is as old as the first reliable fossils of land plants," McCourt noted. "In that way, they're kind of like the coelacanth," a lobe-finned fish believed to be extinct until it was caught off the coast of Africa about 60 years ago. Like these primitive fish that are considered relatives of animals that invaded land, stoneworts have remained unchanged in form up to modern times. "But the oldest stonewort fossils look basically like the ones you can find today in shallow ponds worldwide, so the first land plants must have evolved from a common ancestor with stoneworts much earlier-maybe several hundred million years earlier.

One other common misconception refuted by the group's research is that plants invaded the land from the sea. "You still read this in some textbooks," said McCourt. "But the stoneworts and several other near-relatives of land plants all grow in freshwater or mildly brackish water at most, and we have no evidence that they ever lived in seawater. That means that the first land plants probably invaded from a beachhead at the edge of freshwater streams and ponds."

The researchers, including McCourt and graduate students Kenneth G. Karol, Matthew T. Cimino, and their professor, Dr. Charles F. Delwiche at the University of Maryland are hopeful that their work can help other scientists develop stoneworts and other green algae as model systems to study how the features that make land plants so successful evolved from simpler structures in their green algal relatives.

This research was funded through a grant from the National Science Foundation's Partnerships to Enhance Expertise in Taxonomy (PEET) program.

FAO teams up with experts to suggest policy fixes

3 March 2005, Rome - It was in a fishing village on the Ugandan shores of Lake Victoria in 1982 that a new and terrible disease began to affect large numbers of people in Central Africa. At the time, the illness was known only as "Slim," due to the wasting affect it had on its victims' bodies.

In the years since, the disease -- today all too familiar to us as HIV/AIDS -- has evolved into a pandemic whose impacts are felt by people from all walks of life, in communities all around the world.

Some people, however, are more at risk of contracting the disease than others. Such "high risk" groups include sex workers, long-distance truck drivers, and urban youth.

But the population among whom HIV/AIDS was first identified in epidemic form -- fisherfolk -- has until recently been overlooked, with the consequence that they have been left largely beyond the reach of prevention, treatment, and mitigation programmes.

This neglect may be having devastating consequences, says Ichiro Nomura, FAO Assistant-Director General for Fisheries.

He points out that in recent years it has become evident that fishing communities in many developing countries in Africa, South- and South-East Asia and Central America suffer from very high rates of HIV infection -- rates that can be five to ten times higher than those in the general population.

"These elevated rates of HIV prevalence and the alarming death rate from AIDS in these communities place the affected fishing communities among the so-called 'high risk groups' that merit special consideration in the fight against the disease," Mr. Nomura says.

Far-reaching side effects

The burden of dealing with HIV/AIDS puts additional stresses on fishing households, preventing them from accumulating assets with their fishing income or spending it to improve their household food security.

Beyond these immediate impacts, HIV/AIDS is also undermining entire food production systems, systems that people depend on for their food and incomes. Fishing and a whole range of economic activities associated with it -- processing, transporting, net making -- make crucial contributions to household incomes in many developing countries, boosting food security and allowing a richer, healthier diet.

And according to Benoit Horemans, Coordinator of the FAO/DFID Sustainable Fisheries Livelihood Programme in West Africa, the disease also erodes reliance on responsible fishing practices.

"For communities with very high levels of AIDS deaths, like those around Lake Victoria, fatalism can erode the commitment to long-term stewardship of fisheries resources," he explains.

These trends replicate what is occurring in the food production sectors of other rural communities ravaged by the disease, says Marcela Villarreal, FAO's focal point for HIV/AIDS.

"What has become clear is that HIV/AIDS is more than just a health problem, it is also a threat to sustainable rural development," she emphasizes.

Workshop puts spotlight on AIDS in fishing communities

Since 1988 FAO has been drawing attention to the implications that HIV/AIDS has for food and production systems in the developing world.

The Organization has developed a strategic framework for addressing the disease's repercussions on poverty, nutrition, food security and rural livelihoods, which includes a focus on fishing communities.

Working with international donor agencies like UK's DFID and Germany's GTZ, FAO is also supporting country- and sectoral studies on the disease in fisheries.

More recently, FAO has joined forces with a group of leading international experts on HIV in fishing communities to strategize on how to better carry out HIV/AIDS treatment and prevention programmes among fisherfolk.

The group recently came together at FAO headquarters to discuss that challenge -- and possible solutions.

Vulnerability to HIV/AIDS in fishing communities stems from a complex set of factors, according to presentations made at the workshop. These include: the mobility of many fishers; the fact that they have access to a daily cash income in an overall context of poverty and vulnerability; the availability of commercial sex in fishing ports, and; the subcultures of risk-taking found among some fishermen.

Planning an effective response

During their discussions the group produced a policy brief aimed at providing governments, international donors, relief agencies and others with recommendations on how to better respond to AIDS in fishing communities.

One of its main recommendations: tailoring health outreach programs to match the rhythms of daily life in fishing communities. Health ministries need to improve access to testing, advice, and care facilities by adapting them to the mobility and irregular working hours in fishing communities.

"Free testing or counselling won't do much good if it is scheduled at a time when everybody is out fishing," explains Mr Horemans. "Outreach programs need to be suited to the community in order to be effective."

Their mobility also means that fisherfolk can be left out of efforts to distribute anti-retroviral therapies in the developing world, participants at the FAO workshop also noted in their brief.

These challenges are why close collaboration between health sector professionals, rural development programmes, and organizations with specific fisheries-sector knowledge are required to effectively tackle the problem, according to Mr Horemans.

Control efforts still underfunded - combating bird flu should become top priority

25 February 2005, Ho Chi Minh City, Viet Nam/Rome -- An international conference on avian influenza in Asia has expressed major concern about the bird flu situation in the region.

Chief Veterinary Officers from 28 countries called upon governments in the region and the international community to make the fight against the lethal virus a top priority and to commit more financial resources to national and regional anti-bird flu campaigns.

The three-day conference ended today. It was jointly organized by the UN Food and Agriculture Organization (FAO) and the World Organisation for Animal Health (OIE), in collaboration with the World Health Organization (WHO).

Animal and human health experts agreed that one year after the bird flu crisis, progress has been made in the early detection of and rapid response to the disease. There are fewer outbreaks in the region today than were recorded one year ago.

However, the virus is still circulating among poultry, ducks and wildlife in the region and continues to pose a serious threat to human health and animals.

More funds and more vigorous bird flu control campaigns in affected countries could help to control the disease in birds and thus avoid the risk of a global avian influenza pandemic in humans.

Countries hit by the virus should take a more proactive approach to combat the disease at its origin. Funding for this approach is considered essential.

Continuous threat to humans

The virus circulation in poultry-producing rural and urban areas and marketplaces requires more attention, according to conference participants. As long as the virus continues to circulate among animals, it will remain a threat to humans.

Massive public awareness campaigns should sensitize poultry producers and consumers throughout the food chain about bird flu related risks. Farmers and veterinarians should become the main allies in detecting the virus at the earliest stage possible to trigger immediate control interventions.

Spreading the disease

The conference also recognized the link between farming systems and the spread of the virus, especially the proximity between farmed chickens and ducks in many backyard farms contributing to the circulation of the disease. In addition, the movement and marketing of live animals, not controlled by veterinarians, are a major cause of the spread of the disease.

The conference recommended several strategies to minimize the risk of virus transmission between species and to therefore protect humans. These include segregation in farm settings of chickens, ducks, and other animals such as pigs and a reduction in contact between these animals and humans.

Delegates called upon the global community to help with the financing of these costly but vital changes. More than $100 million would be needed to urgently strengthen animal health services and laboratories to improve virus detection and its ultimate eradication.

Several hundred million dollars would be required to finance the restocking of infected poultry flocks and to restructure the whole sector.

Bird flu control campaigns (virus detection, culling, biosecurity and vaccination) should respect social, economic and cultural conditions in each affected country.

The meeting agreed that vaccines can be a strong weapon in the fight against the disease in poultry. The possibility of vaccinating ducks should be explored.

However, the conference acknowledged the need to further study conditions in which vaccines can be delivered with minimum risk to human health.

The bird flu virus does not respect borders and needs a strong regional response. Existing regional cooperation networks recently established by FAO should be extended. Without proper funding, these networks will cease their activities within the next six months.

Countries are urged to report occurrences of the disease to the OIE in a timely and transparent manner. They should also share information on disease outbreaks and campaigns with neighbouring countries.

There are between 25 and 40 million village backyard poultry farmers in Cambodia, Indonesia, the Lao People's Democratic Republic, Thailand and Viet Nam. The majority of poor farmers keep poultry for income and food security.

In recent years, NRI has used its experience in fisheries and aquatic resource management to establish and lead a multi-donor Support unit for International Fisheries and Aquatic Research ( SIFAR ), based at FAO in Rome. SIFAR aims to develop a better international response to the research needs of developing countries, and its activities are focused on generating improved understanding of: the institutional and policy constraints on fisheries management; and the impacts of trade liberalization on poverty and vulnerability in developing countries. SIFAR's objectives include the identification of options for national and international fisheries, and for trade policies that promote sustainable development.

Fragile inland and coastal aquatic ecosystems often encompass artisanal fisheries that represent a key source of food and income for vulnerable populations. NRI provides advice on: cost-effective non-destructive fishing methods; post-harvest handling, processing, quality management, and trade; analysis of trade-offs between efficiency and welfare; and environmental impacts of fisheries. For example, in the Caribbean, NRI managed a DFID research project to describe and quantify coastal resources, livelihoods and impacts. The principal output was a region-wide database of the current state of coastal resources. Other outputs included: stakeholder perceptions of livelihoods, poverty and vulnerability; a synthesis and comparison of small-island, large-island and mainland community resource and problems; and proposals for future support to sustainable development in Caribbean coastal communities.

STREAM launch STREAM (Support to Regional Aquatic Resources Management) is a new initiative launched this month. Its objectives are to obtain a better understanding of poor peoples' livelihoods and how to use relevant existing and emerging information more effectively, in order to enable people to exert greater influence over the policies and processes that impact on their lives. It is explained in a STREAM brochure, and memorandum summary that are now available (contact ereby@enaca.org ). The development of country-specific implementation strategies for two pilot countries (Cambodia and Viet Nam) is a priority action over the coming months.

A diverse coalition of partners supporting the start-up of STREAM has worked together over the last 18 months to negotiate a shared vision, input different experiences and expertise into the planning process, and implement pilot activities in Cambodia and Viet Nam. This coalition will increase in size and diversity as STREAM expands into other countries, and awareness and understanding of the initiative increases among other stakeholders. The founding partners are: the Network of Aquaculture Centres in Asia-Pacific (NACA), the Department for International Development of the United Kingdom (DFID), the Food and Agriculture Organization of the United Nations (FAO) and the INGO Voluntary Service Overseas (VSO). STREAM is designed within NACA's 5-year Work Programme cycle to support stakeholders to achieve the long-term objectives.