EXTINCTION 100 TIMES MORE LIKELY NOW

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Extinction risks vastly underestimated: study

Wed Jul 2, 1:41 PM ET

Some endangered species may face an extinction risk that is up to a hundred times greater than previously thought, according to a study released Wednesday.

By overlooking random differences between individuals in a given population, researchers may have badly underestimated the perils confronting threatened wildlife, it said.

"Many larger populations previously considered relatively safe would actually be at risk," Brett Melbourne, a professor at the University of Colorado and the study's lead author, told AFP.

There are more than 16,000 species worldwide threatened with extinction, according to the International Union for Conservation of Nature (IUCN).

One in four mammals, one in eight birds and one in three amphibians are on the IUCN's endangered species "Red List".

In a study released on Wednesday by the journal Nature, Melbourne said the current models used draw up such lists typically look only at two risk factors.

One is the individual deaths within a small population, such as Indian tigers or rare whales.

When a species dwindles beyond a certain point, even the loss of a handful of individuals can have devastating long-term consequences, Melbourne explained.

There are less than 400 specimens of several species of whale, for example, and probably no more than 4,000 tigers roaming in the wild.

The second commonly-used factor is environmental conditions that can influence birth and death rates, such as habitat destruction, or fluctuations in temperature or rainfall, both of which can be linked to climate change.

Melbourne and co-author Alan Hastings from the University of California at Davis argue that these factors must be widened in order to give a fuller picture of extinction risk.

They say that two other determinants must be taken into account: male-to-female ratios in a species, and a wider definition of randomness in individual births and deaths.

These complex variables can determine whether a fragile population can overcome a sudden decline in numbers, such as through habitat loss, or whether it will be wiped out.

"This seems subtle and technical, but it turns out to be important," Melbourne said in an email. "Population sizes might need to be much larger for species to be relatively safe from extinction."

The new mathematical tool will be most useful for biologists who want to assess the survival prospects of species such as marine fish whose numbers can suddenly fluctuate and for which data is limited, the authors say.

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RAIN, RAIN: GO AWAY!

It has been raining here for three days and nights. Not just rain, but downpours with high winds! Every tiny defect in the galvanized iron roofs of the people in Costa Rica has been exaggerated many fold. We've got big pots scattered all over the house and/or attic to collect the water from the leaks. It is impossible now to do any repairs because we haven't had even ten minutes of sunshine in which to work. This is a Central American country not far from the equator. And it has been COLD!

My wood-burning stove's chimney pipe burnt through a month ago, and I've been waiting for my neighbor and builder, Carlos, to finish another project so that he can come over here and make a new chimney. Now, with a big hole in the chimney pipe, I cannot use the stove to heat the house and dry out some of the air. And my solar hot water heater is no longer producing hot water. So no hot showers. I do have LP gas for my kitchen stove and we are only losing electricity sporatically (as usual) so no big problems with cooking or lights, etc. I have a huge back-up water tank holding potable water in case of national potable water service failures, but that doesn't look as though it will be a problem.

I have chronic sinus problems and now I've been having sinus bleeds and much pain for two days. A result of very low pressure systems over the country. Ouch!

But it could be much, much worse. We did have three little earthquakes a couple of days ago, but they caused no damage, thank goodness! Guanacaste Province in the north had been in the depths of a very serious drought! Cattle died and crops withered. Now they are suddenly dealing with major flooding.

I have just learned that this nasty weather system has been declared a tropical storm and is moving toward Nicaragua where it is expected to make landfall. Poor Nicas! The economy of Nicaragua is in shambles and Costa Rica is flooded with illegal immigrants fleeing starvation and seeking some kind of income to send to families in Nicaragua. So that poor nation certainly doesn't need more troubles! The tiny isthmus called Central America doesn't need more trouble. It has been plagued by war, disease, hunger, floods, earthquakes, and dictatorships! Costa Rica and Panama are making some progress toward a better life for its citizens, but the rest of Central America still has a long, long way to go.

Does it seem that this year has already been one of the most devastating in memory for natural disasters worldwide? Or am I seeing things with a jaundiced eye?

It is hard for people who have enough and more than enough security to carry them through any rough times to realize what the reality is for the people caught in the aftermath of a natural disaster. It is worse than a return to the stone age in terms of living day to day. It is surviving a minute at a time in constant fear and post-traumatic stress without enough food, water, or shelter and with the menacing possibilities that even worse tragedies lie ahead for survivors. We lucky few in this world who never have to live for months without bathing, with only enough water to sip a bit at a time, with scavenging for food, with cold, wet, and hunger gnawing at their bodies while grief and fear and anger battle in their souls - we lucky few cannot begin to imagine the true horror of these disasters.

And I wonder if this is not just a fluke of nature, but the beginning of the end. Is it too late to save life on this planet? Are we now facing another great extinction such as the one that wiped out the dinosaurs?

Don't just sit there shrugging! Do something useful! It's now or never, Folks!