Wednesday, April 22, 2009

Damaged Barrier Reef coral makes 'spectacular' recovery

Lucky combination of circumstances means corals have unexpectedly grown back within a year

Corals at the Great Barrier Reef

Coral at the Great Barrier Reef Photograph: HO/REUTERS

Sections of coral reef in Australia's Great Barrier Reef have made a "spectacular" recovery from a devastating bleaching event three years ago, marine scientists say.

In 2006, high sea temperatures caused severe coral bleaching in the Keppell Islands, in the southern part of the reef — the largest coral reef system in the world. The damaged reefs were then covered by a single species of seaweed which threatened to suffocate the coral and cause further loss.

A "lucky combination" of rare circumstances has meant the reef has been able to make a recovery. Abundant corals have reestablished themselves in a single year, say the researchers from the University of Queensland's Centre for Marine Studies and the ARC Centre of Excellence for Coral Reef Studies (CoECRS).

"Three factors were critical," said Dr Guillermo Diaz-Pulido. "The first was exceptionally high regrowth of fragments of surviving coral tissue. The second was an unusual seasonal dieback in the seaweeds, and the third was the presence of a highly competitive coral species, which was able to outgrow the seaweed."

Coral bleaching occurs in higher sea temperatures when the coral lose the symbiotic algae they need to survive. The reefs then lose their colour and become more susceptible to death from starvation or disease.

The findings are important as it is extremely rare to see reports of reefs that bounce back from mass coral bleaching or other human impacts in less than a decade or two, the scientists said. The study is published in the online journal PLoS one.

"The exceptional aspect was that corals recovered by rapidly regrowing from surviving tissue," said Dr Sophie Dove, also from CoECRS and The University of Queensland.

"Recovery of corals is usually thought to depend on sexual reproduction and the settlement and growth of new corals arriving from other reefs. This study demonstrates that for fast-growing coral species asexual reproduction is a vital component of reef resilience."

Last year, a major global study found that coral reefs did have the ability to recover after major bleaching events, such as the one caused by the El NiƱo in 1998.

David Obura, the chairman of the International Union for Conservation of Nature climate change and coral reefs working group involved with the report, said: "Ten years after the world's biggest coral bleaching event, we know that reefs can recover – given the chance. Unfortunately, impacts on the scale of 1998 will reoccur in the near future, and there's no time to lose if we want to give reefs and people a chance to suffer as little as possible."

Coral reefs are crucial to the livelihoods of millions of coastal dwellers around the world and contain a huge range of biodiversity. The UN's Millennium Ecosystem Assessment says reefs are worth about $30bn annually to the global economy through tourism, fisheries and coastal protection.

But the ecosystems are under threat worldwide from overfishing, coastal development and runoff from the land, and in some areas, tourism impacts. Natural disasters such as the earthquake that triggered the Indian Ocean tsunami in 2004 have also caused reef loss.

Climate change poses the biggest threat to reefs however, as emissions of carbon dioxide make seawater increasingly acidic.

Last year a study showed that one-fifth of the world's coral reefs have died or been destroyed and the remainder are increasingly vulnerable to the effects of climate change.

The Global Coral Reef Monitoring Network says many surviving reefs could be lost over the coming decades as CO2 emissions continue to increase.

Budget 2009: Darling promises 34% emissions cuts with world's first binding carbon budgets

Environmentalists warn that emissions targets are out of date

If they can actually do it, the government's pledge to cut global warming emissions by one third in just over a decade should transform the way the UK economy works.

However, critics warned that the cuts would still not be enough to avoid dangerous climate change, and warned that other spending pledges were not nearly enough to meet the target.

Darling has now promised to cut greenhouse gases by 34% by 2020 through so-called carbon budgets, which fix binding limits on greenhouse gas emissions over five-year periods. The 34% target is in line with the advice of the government's independent watchdog, the Committee on Climate Change. "This represents a step change in the UK ambition on climate change," said the budget report.

The budget report said the government "aims" to do this without purchasing controversial carbon credits from cuts made in other countries, but said these "offsets" could be a "fallback option". It also said the target cut would be higher if there was "satisfactory" global agreement on cutting emissions, but stopped short of committing to the higher 42% cut recommended by the CCC in those circumstances.

"These budgets give industry the certainty needed to develop and use low carbon technology – cutting emissions, creating new businesses and jobs," said the chancellor.

Nobody expected the government to reject the emissions targets put forward by its watchdog, which are designed to help reach a promised reduction of 80% by the middle of this century.

However, the formal announcement makes the UK the first country in the world to set legally binding targets.

Environmental campaigners and business groups commended the government on committing itself to firm targets. However, there were immediate warnings that not enough was being done.

Friends of the Earth, the charity which led a mass public campaign for the Climate Change Act which created the targets, said the 34% cut was no longer enough.

"Setting the first ever carbon budgets is a ground-breaking step - but the government has ignored the latest advice from leading climate scientists and set targets that are completely inadequate," said Andy Atkins, the organisation's executive director. "A 42% cut by 2020 is the minimum required if we are to play our part in avoiding dangerous climate change."

There was also widespread criticism that the rest of the budget did not include enough money for renewable energy like wind and tidal power, and energy efficiency for homes and other buildings. The budget also promised up to four "demonstration" projects for carbon capture and storage for coal and gas power plants, and £60m of new spending on research and development of the unproven technology, but critics said these partial capture schemes were not enough if the government goes ahead with plans for up to eight new coal plants.

James Cameron, vice-chairman of Climate Change Capital, a low-carbon investment fund with more than US$1.5bn (£1bn) under management, said: "The idea of a carbon budget is to be applauded and must become a permanent feature of how we direct our economy. But the reality is that creating a low carbon economy requires more than high-level commitment. The scale of investment required is huge, and thus far the commitments to stimulate the economy and reduce emissions have been small gestures, albeit in the right direction. They have identified the correct areas to be targeting with strategic intervention but the orders of magnitude are much too small."

The budget report said a full strategy on how the targets will be met is due this summer, but that the "latest government modelling" showed it was on course to meet the 2020 and two interim targets.

"The strategy will strengthen the long-term policy framework, taking into account recent consultations on heat and energy saving, renewable energy and zero carbon homes," added the report.

Severe Texas Drought Threatens Coastal Wildlife

From: Ana Campoy, Wall Street Journal

A severe drought gripping Texas is causing unusually salty conditions along the Gulf Coast, upsetting the region's ecological balance and threatening coastal wildlife including oysters, crabs and whooping cranes, the most endangered crane species.

The drought is one of the driest on record for Texas and is currently the worst in the U.S., which has seen persistent dry weather across several Western states, Florida and even Hawaii, according to academic and government monitors. The scarcity of rain has reduced fresh-water flow from rivers and streams into coastal marshes, estuaries and bays that normally dilute the salt content of water from the Gulf of Mexico.

This spring, the only migrating whooping-crane flock that exists in the wild lost 23 of its 270 members to hunger and disease brought on by the dry weather, said Tom Stehn, U.S. Fish and Wildlife Service whooping-crane coordinator. That is a big blow to conservation programs that have worked over the past 50 years to slowly increase the number of cranes.

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New study shows widespread and substantial declines in wildlife in Kenya's Masai Mara

From: Jeff Haskins/ILRI , Muthoni Njiru/CGIAR

Nairobi, Kenya (22 April 2009)—Populations of major wild grazing animals that are the heart and soul of Kenya's cherished and heavily visited Masai Mara National Reserve—including giraffes, hartebeest, impala, and warthogs—have "decreased substantially" in only 15 years as they compete for survival with a growing concentration of human settlements in the region, according to a new study published today in the May 2009 issue of the British Journal of Zoology.

The study, analysed by researchers at the Nairobi-based International Livestock Research Institute (ILRI) and led and funded by World Wide Fund for Nature (WWF), is based on rigorous, monthly monitoring between 1989 and 2003 of seven "ungulate," or hoofed, species in the Maasai Mara National Reserve, which covers some 1500 square kilometers in southwestern Kenya. Scientists found that a total of six species—giraffes, hartebeest, impala, warthogs, topis and waterbuck—declined markedly and persistently throughout the reserve.

The study provides the most detailed evidence to date on declines in the ungulate populations in the Mara and how this phenomenon is linked to the rapid expansion of human populations near the boundaries of the reserve. For example, an analysis of the monthly sample counts indicates that the losses were as high as 95 percent for giraffes, 80 percent for warthogs, 76 percent for hartebeest, and 67 percent for impala. Researchers say the declines they documented are supported by previous studies that have found dramatic drops in the reserve of once abundant wildebeest, gazelles and zebras.

"The situation we documented paints a bleak picture and requires urgent and decisive action if we want to save this treasure from disaster," said Joseph Ogutu, the lead author of the study and a statistical ecologist at ILRI. "Our study offers the best evidence to date that wildlife losses in the reserve are widespread and substantial, and that these trends are likely linked to the steady increase in human settlements on lands adjacent to the reserve."

Researchers found the growing human population has diminished the wild animal population by usurping wildlife grazing territory for crop and livestock production to support their families. Some traditional farming cultures to the west and southwest of the Mara continue to hunt wildlife inside the Mara Reserve, which is illegal, for food and profit.

The Mara National Reserve is located in the northernmost section of the Mara—Serengeti ecosystem in East Africa. The reserve is bounded by Tanzania's Serengeti National Park to the south, Maasai pastoral ranches to the north and east, and crop farming to the west. The area is world-famous for its exceptional wildlife population and an annual migration of nearly two million wildebeest, zebra and other wildlife across the Serengeti and Mara plains.

Ogutu and his colleagues focused much of their attention on the rapid changes occurring in the large territories around the Mara Reserve known as the Mara ranchlands, which are home to the Maasai. Until recently, most Maasai were semi-nomadic herders—known for their warrior culture and colorful red toga-style dress—who co-existed easily with the wildlife in the region.

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