Thursday, February 28, 2019

When it comes to climate change, a rat in the ocean is our canary in the coal mine. And insects are next.

This is the first of a two-part series on the climate change catastrophe assured to doom our planet - unless we do some pretty drastic things to stop it. The horizon is not weeks or months, to be sure, but it’s not too many years away. In this part I feature some new reports on signs of climate change - the extinction of species.

Extinction
Extinction is forever.
Bramble Cay Melomys has been declared
extinct as a result of climate change

You don’t expect a rat in the ocean. Neither did this rat expect to end its life in an ocean. But it and its brethren are gone - wiped out - extinct - from the loss of habitat due to rising sea levels. If we do not take heed, this little fellow could be a model of what will happen to our own species.

CNN reports on the Australian mammal becomes first to go extinct due to climate change.

A small brown rat which lived on a tiny island off northern Australia is the world’s first mammal known to have become extinct due to “human-induced climate change,” the government says.

The Bramble Cay melomys inhabited a small coral island on the Great Barrier Reef, measuring about five hectares (12 acres) and located in the Torres Strait, between Queensland state and Papua New Guinea.

The cause of its extinction was “almost certainly ocean inundation” from rising sea levels over the past decade, which had led to “dramatic habitat loss,” according to the 2016 report.

If temperatures continue to rise, nearly 8% of all species worldwide could become extinct, a 2015 study by the University of Connecticut found. Australia, New Zealand and South America are considered to be at highest risk

Insectageddon

Alarm bells should be ringing about the die-off of insects. The New Zealand publication, “stuff”, reports on an Insectageddon: a global crisis of insect extinction and population decline.

A recent review has demonstrated a “dreadful state of insect biodiversity in the world, as almost half of the species are rapidly declining and a third are being threatened with extinction”. This should be a substantial wakeup call. You should be concerned.

The review examined 73 studies that repeatedly surveyed insects for 10 years. Their analysis included work from Germany showing a 76 per cent decline in flying insect biomass over 27 years.

This insect Armageddon or “insectageddon” is a global phenomenon. Puerto Rico was found to have experienced up to 98 percent biomass loss in some rainforest habitats over a 36-year period.

New Zealand insects are in crisis too. We have very little data for the vast majority of our bugs.

Probably the best audit so far has shown 32.5 per cent of the invertebrate species for which we have data are threatened or at risk. A total of 49 per cent of our carabid beetle species are threatened or at risk. Extinctions have already occurred.

Entomologists are in agreement that an “insectageddon” is happening here: we’ve seen what is probably a long and gradual decline in insect species and abundance over several decades.

What is causing the rapid global decline of insects? The study points to habitat loss by conversion to intensive agriculture and urbanisation, pollution by synthetic pesticides and fertilisers, pathogens and introduced species, as well as climate change.

This insectageddon is catastrophic. …

… . Previous insectageddon studies have been published, with supporting media coverage and statements from other scientists (“if we lose the insects, then everything is going to collapse”). But then little else happens.

… Just as the insectageddon is a worldwide phenomenon, the lack of government action is similarly near global. …

The Guardian also reports on Plummeting insect numbers ‘threaten collapse of nature’. Exclusive: Insects could vanish within a century at current rate of decline, says global review.

The world’s insects are hurtling down the path to extinction, threatening a “catastrophic collapse of nature’s ecosystems”, according to the first global scientific review.

More than 40% of insect species are declining and a third are endangered, the analysis found. The rate of extinction is eight times faster than that of mammals, birds and reptiles. The total mass of insects is falling by a precipitous 2.5% a year, according to the best data available, suggesting they could vanish within a century.

The planet is at the start of a sixth mass extinction in its history, with huge losses already reported in larger animals that are easier to study. But insects are by far the most varied and abundant animals, outweighing humanity by 17 times. They are “essential” for the proper functioning of all ecosystems, the researchers say, as food for other creatures, pollinators and recyclers of nutrients.

Prof Paul Ehrlich, at Stanford Universityin the US, has seen insects vanish first-hand, through his work on checkerspot butterflies on Stanford’s Jasper Ridge reserve. He first studied them in 1960 but they had all gone by 2000, largely due to climate change.

Ehrlich praised the review, saying: “… that it is human overpopulation and overconsumption that is driving all the things [eradicating insects], including climate change,” he said.

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