Scientists attribute mammal extinction to climate change for the first time

Scientists attribute mammal extinction to climate change for the first time
A melomy from the Torres Strait, which gives an idea of the size of the now-extinct of Bramble Cay melomy
A melomy from the Torres Strait, which gives an idea of the size of the now-extinct  of Bramble Cay melomy
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A grassland melomy, a close relation of the now extinct Bramble Cay melomy
A grassland melomy, a close relation of the now extinct Bramble Cay melomy
A melomy from the Torres Strait, which gives an idea of the size of the now-extinct of Bramble Cay melomy
A melomy from the Torres Strait, which gives an idea of the size of the now-extinct  of Bramble Cay melomy
Bramble Cay in 2011
Bramble Cay in 2011
Bramble Cay in 2014
Bramble Cay in 2014
A Bramble Cay melomy in 2002
A Bramble Cay melomy in 2002
The researchers laid more than 900 traps in their latest survey
The researchers laid more than 900 traps in their latest survey
Researcher Natalie Waller checks a trap for a Bramble Cay melomy
Researcher Natalie Waller checks a trap for a Bramble Cay melomy
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Climate change is by definition a global phenomenon, but there are few locations feeling its immediate impacts like Australia's Great Barrier Reef. Just a month after local scientists were left reeling as warming seas triggered the worst coral bleaching event in its history, researchers are now reporting the reef's only endemic mammal species has become extinct as a result of rising sea levels, describing its demise as the first mammal species to be killed off by human-induced global warming.

The Bramble Cay melomy is a rodent that has lived on Bramble Cay, a tiny vegetated island in the Torres Strait off the northern tip off the Great Barrier Reef, for tens of thousands of years. But lately its diminishing population has raised concerns with ecologists, with surveys in the early 2000s detecting no more than 12 individual melomys scurrying about.

"In 2002 and 2004 low numbers of this species were recorded and we were concerned," Dr Luke Leung, ecologist at the University of Queensland, tells us. "By the time we got back to the island in 2011, we found no more of these animals. And the island is very small, you go to the beach and you can see everything. The absence of something is not because you couldn't find it, it's because it is not there anymore."

Bramble Cay in 2011
Bramble Cay in 2011

Leung and his colleagues returned to the island in August and September of 2014 in a last-ditch effort to sniff out any remaining melomys. Their work involved laying more than 900 traps and looking by daylight, but they found not a single trace of the now-extinct rodent.

"When we were there we found evidence of seawater inundation," Leung says. "So we can see the erosion, the tidal ingression onto the cay. The cay has a freshwater supply that supports freshwater plants, and when we were there we saw a major reduction in the plant community. No plants means no food for these vegetarian animals."

Leung and co-author Natalie Waller have just published a report on their findings, recommending that the status of the Bramble Cay melomy from endangered to extinct. In it they report that the area of the cay above high tide has decreased from around 4 ha to 2.5 ha between 1998 and 2014, the smallest size recorded for the island to date. Meanwhile, vegetation coverage dropped from around 2.2 ha to 0.065 ha between 2004 and 2014, a 97 percent loss over a decade.

"It has lost its vegetation cover, it has reduced in size, but the major impact is seawater inundation," says Leung.

The researchers laid more than 900 traps in their latest survey
The researchers laid more than 900 traps in their latest survey

The Queensland Government's Department of Environment and Heritage Protection website lists a number of factors that threatened the survival of the Bramble Cay melomy. The list includes the introduction of weeds, predators, novel diseases, and the fact that they appeared to inbred. But rising sea-levels, more frequent and severe storms and the resulting seawater inundation appears to be what tipped it over the edge.

"We can't really point the finger at any other thing," says Leung. "This species has persisted very well for a very long time on such a small cay. We found evidence of tidal surge killing the plants and leading to the disappearance of this species on the island, so we are very confident that this extinction was caused by climate change."

According to the US Environmental Protection Agency, average global sea levels have risen at a rate of 0.11 to 0.14 in per year (0.28 to 0.36 cm). This is around double the longer-term trend between 1880 and 2013, where they rose at an average rate of 0.06 in (0.15 cm), which followed a preceding period of around 2,000 years with little change. So considering this accelerating trend, it's entirely possible that the Bramble Cay melomys won't be the last island inhabitants to have their worlds washed away by rising sea levels.

"Indigenous communities around the same area have also suffered from increased intensity and frequency of storm surges," says Leung. "Some communities have lost their freshwater supply because of sea levels and seawater surging into their freshwater dam. So it is happening in the Torres Strait in Australia and it is a real wake up call. It's a wake up call for Australia and perhaps a wakeup call for the world."

Leung's report on the extinction of the Bramble Cay melomys can be accessed online here.

Source: University of Queensland

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Wow what a quantum leap from claiming Climate CHANGE [still to scared to call it warming] caused and extinction then immediately stating as fact it is MAN MADE Climate change.
Give me the same dishonesty of the income redistributionists who use global cooling, warming, or the deliberately ambiguous CHANGE scare tactics, and I will pick two points in time to PROVE cooling, warming, change.
Just let me know the phony end result required and I can prove it.
The only people to blame for the existence of the "deniers" are the scare mongers in the global cooling, warming, change scam, who have been caught numerous times altering the data in their OWN emails and demanding to hide the decline.
Well I guess that explains the dinosaurs.
Y'know, with all that extra seawater (from the massively rising sea levels caused by the human-induced global warming) covering all the coral, I'm truly surprised that it has a chance to bleach out. Of course, warmer water is only one of a dozen potential causes of coral bleaching.
Regarding the little melomy meeses, are you sure it isn't exposure to all those powerful honkin' _cellular_towers_ which is killing them, instead of mankind? Or the thousands (millions?) of large birds in their habitat?
In any case, I'm hoping that these folks who are overly sensitive to AGWK (Anthropogenic Global Warming Kumbaya) also prove too sensitive to endure this horrible AGWK much longer. Even though it can't be proven.
Robert in Vancouver
I have lived beside the Pacific Ocean for over 30 years and haven't seen any change to sea levels at all. None. If sea levels were rising it would show up here on piers, seawalls, beaches, and other structures that we observe and measure.
Rising sea levels and most other man-made global warming 'evidence' does not hold up to honest scientific study.
Global warming theories are reported and acted on as if they were proven facts. It works the same as any other religious belief. You believe and act according to script because you want to or because you were taught to. Facts and proof are not required or wanted.
Rann Xeroxx
The climate has always been changing since gases existed on the Earth. The real question is does man exert an significant effect on the climate. The "science" of AGW has not proven that in the least. CO2 is not a significant greenhouse gas and the percent of a percent gas that man has added to the air is nothing.
Derek Howe
I think the world should put their flags at half staff tomorrow, to honor these little mice. They did nothing to deserve this, it was the evil humans who slaughtered them by warming up the planet. lol But seriously, I don't care if a little mouse species dies off. Over the eons the Earth has been here, species have come & gone. All we can do is make sure we are the species that is here to stay.
Daniel Harbin
All throughout history the climate has changed and the world and its inhabitants either changed or perished. One I can see is the Little Ice Age and the effect it had on grain production and therefore all life that revolved around it. People and animals adapted to the new conditions including food sources. Europe went from grains to tubers, or taters asI know em. The weather grew colder and some even speculate that the cold was the reason the USA won the revolutionary war.
Climate changes and it will always change and we and the animals will either adapt or perish.
The item I am looking for in this "Climate Change" science is repeatable results which is the hallmark of what science is all about. The science has models that are about as reliable and truthful as Joe Izzuzu (look him up).
I take a different tack on the global warming issue. You can either believe we have gotten pretty good at science and therefor trust the scientific community, or you can believe that all of our scientific advances were simply luck and we have no real understanding how things work. I'm in the first camp. Further, I believe that science is nothing if it is not predictive. So I'll send to any deniers all the chicken bones you want so that you can divine your futures from tossing them while you chant,"AGW is a lie". But please don't stand in the way of scientific research when you do.
A quick internet search turn this up:
Bramble Cay is a low-lying 9-acre sandy island, half of which is covered in grasses. It sits at the mouth of the Fly River of Papua New Guinea, the largest river by discharge in the south Pacific, with almost the same outflow as the Yukon River in Alaska. Sandy islands in river deltas are highly unstable. Their size and shape changes seasonally from erosion due to river outflow, changing currents, weather systems, etc. It is unusual to find mammals living in these inhospitable places because the ecosystem can change rapidly. Anyone who has ever boated past the tiny barrier islands off the southeast coast of the U.S. or the southern coast of Texas knows what these look like. Birds and crabs are the predominant animals.
It's highly likely that natural erosion is the reason for the rapid change that led to the demise of these rats rather than sea level rise, which averages a minuscule 1.5 mm a year globally, about the same as it's been for 145 years of tide gauge measurements. See the lower graph from tide gauge data at NASA's website:
The upper graph is from satellite measurements and shows roughly double the rate of sea level rise (3.4 mm/yr), but exactly the same trend with no acceleration. Why the satellite measurements differ from tide gauge measurements is subject to debate, but alarmists like to quote the satellite measurements because they're higher, conveniently ignoring the tide gauge data which still shows about half the rate during the same time period. There was no sudden "doubling" of sea level rise. Look at both graphs and you see no sudden jump in sea level rise. The satellite data starts in 1993 and overlaps with the tide gauge measurements and both show essentially the same trend, but the satellite shows double the rate of rise. It's likely that satellite altimeters can't accurately measure sea level to a fraction of a millimeter from hundreds of miles up in orbit.
I did all the homework that Nick Lavars, who wrote this piece, and Natalie Waller and Luke Leung from the University of Queensland couldn't be bothered to. Blaming it on "climate change" and "human-caused climate change" is so much more convenient for their narrative.
The report from the University of Queensland verifies what I said about rapid changes and erosion of a small sandy island located in the outflow of the largest river in the south Pacific. Here's the report:
"it is apparent that the island has undergone the marked changes in size and shape during the intervening five-month period...the cay now being larger (3.44 ha cf. 2.48 ha) and more elongate (370 m long in August–September 2014, but only 253 m in 12 March 2014)"
This is a known dynamic of sandy islands near the mouths of large rivers.
"Nevertheless, a worrying finding from the March 2014 assessment was that due to erosion by wind, waves and tides impacting on the island...the cay’s area above high tide had decreased"
"Furthermore, the herbaceous vegetation on Bramble Cay, which provides both food and shelter for the Bramble Cay melomys, declined dramatically from approximately 2.2 ha in 2004 to only 0.065 ha, equivalent to a 97% loss over a decade. Birds roosting amongst this vegetation in March 2014 further reduced habitat availability for the Bramble Cay melomys because the species is known to avoid areas in which numerous seabirds roost at night"
"A change in climatic conditions over this period is one factor that may have driven a decline in herbaceous cover on Bramble Cay"
"A more likely cause of the marked decline in vegetation cover is ocean inundation. With a maximum elevation of only 3 m, Bramble Cay is particularly vulnerable to sea-level rise and the impacts of extreme high water events. Seawater inundation as a result of storms and high tides has previously been identified as a threat to the Bramble Cay melomys because it kills vegetation and reduces the area of habitat present (Dennis 2012)."
It only takes one big storm to inundate and kill vegetation on a small sandy island only 10 feet high. Sure, enough, the report indicates this has happened before:
"Events involving at least the partial inundation of Bramble Cay have been documented on several occasions over the last quarter century"
Sea level rise will, of course, exacerbate erosion as the study explains in great detail. What the study leaves out is the perspective that global sea levels were roughly 16 feet higher during the warmest period of the previous interglacial period 125,000 years ago.
For at least the last 700,000 years earth has cycled between glacial periods (ice ages) followed by interglacials (warm periods) over roughly 100,000+ year periods as the IPCC notes here:
You're welcome.
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