Special day for the ozone layer

Ozone, ozone layer, chloro-fluoro carbons... these may be words that you know well. You may have heard these words before and would be hearing them and reading about them once again this week. Why? Because today, September 16, is the International Day for the Preservation of the Ozone Layer or World Ozone Day as it's also known.

This year, the event is even more relevant as it marks the 20th anniversary of the signing of the Montreal Protocol on Substances that Deplete the Ozone Layer, the international treaty to protect the stratospheric

 ozone layer. So, aptly, this year's event is observed under the theme 'Celebrating 20 years of progress in 2007'.

In recognition of the importance of this Protocol and its achievements, various activities are being planned by countries across the world to celebrate this event and to further raise awareness on the protection of the ozone layer. Sri Lanka will also hold many events spearheaded by the Environment Affairs Ministry.

The Montreal Protocol, which was first signed in the city of Montreal, Canada on September 16, 1987, encourages countries to phase out the production and consumption of ozone depleting chemicals; around 191 countries have already signed it.

It includes guidelines such as countries phasing out their annual consumption of harmful substances such as CFC and R22.

The International Day for the Preservation of the Ozone Layer was proclaimed as September 16 by the United Nations General Assembly on December 19, 1994 to commemorate the date on which the Montreal Protocol was signed. States are invited to devote the Day to encourage, at national level, activities that promote the objectives of the Montreal Protocol and its amendments.

You may know that the ozone layer is what protects the Earth from the harmful radiation including UV rays that seeps down to Earth. However, large holes have formed in this layer over the years, as a result of the poisonous chemical substances and gases that humans have been releasing into the atmosphere.

But awareness about the depletion of the ozone layer and its effects has also grown over the years and people are working more towards preserving this layer which is vital for life on Earth.

Alternative ozone-friendly products are now being manufactured widely in all industrialised countries and many developing countries such as India, China and Brazil have also started manufacturing ozone-friendly products. Many modern products such as refrigerators, air-conditioners and chillers have labels denoting that they are ozone-friendly.

So, it's not all bad news, there's still some hope left. Now, that you, the future generation, know the harmful effects of ozone-depleting substances such as CFC, you can do your best to minimise their use and eventually ban them altogether. That should be the message that's sent out on World Ozone Day.

Wrong fish used to save species

A 20-year government effort to restore the population of an endangered native trout in Colorado, USA has made little progress because biologists have been stocking some of the waterways with the wrong fish, a new study says.

Advances in genetic testing helped biologists discover the error, which was called a potential black eye, but they said there is still hope for restoring the greenback cutthroat trout.

The three-year study, led by University of Colorado researchers and published online in Molecular Ecology, said

 that five of the nine populations believed to be descendants (young) of the endangered trout were actually the more common Colorado River cutthroat trout, which look similar.

The study said the results imply that the effort has "failed to improve the species' status."

Lead author, Jessica Metcalf, who recently completed her doctorate in ecology and evolutionary biology at the university, was optimistic (positive) about the ongoing restoration programme because four populations have been identified as "pure greenback cutthroat trout."

Bruce Rosenlund of the U.S. Fish and Wildlife Service, which is leading the recovery effort, said the agency is reviewing the study.

"The report is just a continuation of different expert inputs provided to the team for consideration for restoration," Rosenlund said.

Colorado and federal biologists have a goal of 20 self-sustaining populations of at least 500 fish each.

The cost of the programme was not available.Greenback cutthroat trout were historically found in the drains of the Arkansas and South Platte rivers in Colorado and a small part of Wyoming. They were declared extinct in 1937 because of overfishing, pollution from mines and competition from non-native fish.

Researchers said remnant (leftover) populations were found in the 1950s in tributaries (waterways) and provided brood stock for fish raised in federal and state hatcheries and released in their native habitat.The fish was added to the federal endangered species list in 1978.The greenback were believed to be in 142 miles of waterways, including in Rocky Mountain National Park, Rosenlund said.

The new study found the greenback cutthroat trout's range is only 11 miles of streams. The research results are a setback but state biologists believe the programme will succeed over the long term, said Tyler Baskfield, Colorado Division of Wildlife spokesman.

"We've been moving fish around in the state since the late 1800s, and now the new science comes in and all of a sudden it's a different playing field," Baskfield said.

University of Colorado professor Andrew Martin, the study's principal investigator, said that while the findings might give the recovery programme a "black eye", the hope is that biologists and agencies will move ahead on recovering the species before it goes extinct.

AP