Article: Earth Pulse

Tuesday July 7, 2009

Lost forever

More than 800 animal and plant species have gone extinct in the past five centuries while nearly 17,000 are now threatened with extinction, the International Union for Conservation of Nature says. An analysis of these numbers indicates the international community will fail to meet its 2010 goal of bolstering biodiversity, a commitment made by most governments in 2002.

The northern spotted owl of the United States is one of the thousands of species threatened with extinction.

Based on data released in 2008 in the union's Red List, the new IUCN analysis is being released now to precede the 2010 target year and to draw a connection between crises in the financial and environmental realms, said report editor Jean-Christophe Vie.

The new analysis shows 869 species became extinct or extinct in the wild since the year 1500 while 290 more species are considered critically endangered and possibly extinct. Species threatened with extinction include nearly one-third of amphibians, more than one in eight birds and nearly a quarter of mammals. By comparison, the 2004 Red List showed 784 extinctions since 1500.

The report said this is not a comprehensive list with only 2.7% of the 1.8 million described species analysed. The number of extinctions is "a gross underestimate but it does provide a useful snapshot of what is happening to all forms of life on Earth," the study authors wrote.

For land-based species, the main threat is habitat destruction through farming, logging and development. Climate change is not now the main threat to biodiversity but that could change, the report said.

In examining 17,000 species of birds, amphibians and reef-building corals, the report found a significant proportion that are not now threatened are susceptible to climate change, including 30% of birds, 51% of corals and 41% of amphibians that are not threatened now. – Reuters

Dying fields

The world's seagrass meadows, a critical habitat for marine life and profit-maker for the fishing industry, are in decline due to coastal development and the losses are accelerating, according to a global study.

The study found 58% of seagrass meadows are decli­ning and the rate of annual loss has accelerated from about 1% before 1940 to 7% per year since 1990. The study, based on more than 200 surveys and 1,800 observations dating back to 1879, found that seagrasses are disappearing at rates similar to coral reefs and tropical rainforests.

Scientists say seagrass processes waste dumped into the sea, helps stabilise ocean-bottom sediments in coastal areas to reduce erosion, provide nurseries for fish and shellfish and feeding grounds for larger marine creatures, including those that live in coral reefs. But the grasses can be damaged by polluted water from coastal development, decreasing water clarity, and by dredging and filling of meadows.

The study, by a team of scientists from the United States, Australia and Spain, found that 51,000 sqkm (29%) of known seagrass meadows have disappeared since 1879. In the early 20th century, heavy seagrass losses were noted in North America and Europe, where the industrial revolution led to rapid coastal development. Today, population growth in the regions bordering the Pacific and Indian Oceans are likely leading to the heaviest losses of seagrass, but those regions lack the scientific infrastructure to assess the loss, said Prof James Fourqurean of the Florida International University and a co-author of the study.

He said mitigation efforts have had some success in saving and restoring seagrass. For example, in Florida, where treated sewage water is often dumped in the ocean, water managers in Tampa changed their method of treating wastewater and failing seagrasses rebounded. – Reuters

Belching cows

Canadian scientists are breeding a special type of cow designed to burp less, a breakthrough that could reduce a big source of greenhouse gases responsible for global warming. Cows are responsible for nearly three-quarters of total methane emissions, most of it coming from bovine burps. Methane is 20 times more potent than carbon dioxide as a greenhouse gas.

Prof Stephen Moore of the University of Alberta is examining the genes responsible for methane produced from a cow's four stomachs in order to breed more environmentally friendly cows. He completed primary tests using traditional techniques to breed efficient animals that produce 25% less methane than less efficient animals. But more work needs to be done before the long-term impact is known. Moore's study was published earlier this year in the Journal of Animal Science.

"We are working on producing diagnostic markers for efficient animals. We are looking at the next generation of technologies that will enable us to determine the genetics of an animal through a blood test or testing some hairs that you might pluck from the animal," said Moore.

Another method already being used to reduce methane emissions is feeding livestock a diet higher in energy and rich in edible oils, which ferment less than grass or low-­quality feed.

Yoghurt producer Stonyfield Farm reduced emissions from their cows on an average of 12% by adding alfalfa, flax or hemp to livestock feed on a small number of its farms. – Reuters

This article was taken from: The Star Online: Go Green Live Green 7 July 2009