From the busy BEES at Drexel University, worry that beach sand temperature 40 to 50 centimeters deep will be affected by the global warming air temperature rise of 0.8C over the last century, projected to increase. The models identified this as the leading projected cause of climate-related decline in leatherback turtles. They say “if actual climate patterns follow projections in the study, the eastern Pacific population of leatherback turtles will decline by 75 percent by the year 2100.” Gosh.
But they write in their press release as if the projections are actually happening:
Leatherback turtles, Spotila says, are in critical need of human help to survive. “Warming climate is killing eggs and hatchlings,” Spotila said. “Action is needed, both to mitigate this effect and, ultimately, to reverse it to avoid extinction. We need to change fishing practices that kill turtles at sea, intervene to cool the beach to save the developing eggs and find a way to stop global warming. Otherwise, the leatherback and many other species will be lost.”
It makes you wonder how the turtles ever survived the Roman Warm Period or the Medieval Warm Period or the early part of the Holocene?
Credit: Jolene Bertoldi / ZA Photos, via Flickr
Rising heat at the beach threatens largest sea turtles, climate change models show
PHILADELPHIA (July 1, 2012)—For eastern Pacific populations of leatherback turtles, the 21st century could be the last. New research suggests that climate change could exacerbate existing threats and nearly wipe out the population. Deaths of turtle eggs and hatchlings in nests buried at hotter, drier beaches are the leading projected cause of the potential climate-related decline, according to a new study in the journal Nature Climate Change by a research team from Drexel University, Princeton University, other institutions and government agencies.
Leatherbacks, the largest sea turtle species, are among the most critically endangered due to a combination of historical and ongoing threats including egg poaching at nesting beaches and juvenile and adult turtles being caught in fishing operations. The new research on climate dynamics suggests that climate change could impede this population’s ability to recover. If actual climate patterns follow projections in the study, the eastern Pacific population of leatherback turtles will decline by 75 percent by the year 2100.
Modeling the Ebb and Flow of Turtle Hatching with Climate Variation
“We used three models of this leatherback population to construct a climate-forced population dynamics model. Two parts were based on the population’s observed sensitivity to the nesting beach climate and one part was based on its sensitivity to the ocean climate,” said the study’s lead author Dr. Vincent Saba, a research fishery biologist with the NOAA National Marine Fisheries Service Northeast Fisheries Science Center, visiting research collaborator at Princeton University, and a Drexel University alumnus.
Leatherback turtle births naturally ebb and flow from year to year in response to climate variations, with more hatchlings, and rare pulses of male hatchlings, entering the eastern Pacific Ocean in cooler, rainier years. Female turtles are more likely to return to nesting beaches in Costa Rica to lay eggs in years when they have more jellyfish to eat, and jellyfish in the eastern Pacific are likely more abundant during cooler seasons. Turtle eggs and hatchlings are also more likely to survive in these cooler, rainier seasons associated with the La Niña climate phase, as this research team recently reported in the journal PLoS ONE. In addition, temperature inside the nest affects turtles’ sex ratio, with most male hatchlings emerging during cooler, rainier seasons to join the predominantly-female turtle population.
The researchers applied Saba’s combined model of these population dynamics to seven climate model projections assessed by the Intergovernmental Panel on Climate Change (IPCC). The climate model projections were chosen based on their ability to model El Niño Southern Oscillation (ENSO) patterns on the temperature and precipitation in the region of Costa Rica where this team has conducted long-term leatherback studies.
Hot Beaches, More Warm Years Threaten Turtles’ Recovery
The resulting projections indicate that warmer, drier years will become increasingly frequent in Central America throughout this century. High egg and hatchling mortality associated with warmer, drier beach conditions was the most significant cause of the projected climate-related population decline: This nesting population of leatherbacks could decline by 7 percent per decade, or 75 percent overall by the year 2100.
The population is already critically low.
“In 1990, there were 1,500 turtles nesting on the Playa Grande beach,” said Dr. James Spotila, the Betz Chair Professor of Environmental Science in the College of Arts and Sciences at Drexel. “Now, there are 30 to 40 nesting females per season.”
Spotila, a co-author of the study, has been studying leatherback turtles at Playa Grande in Costa Rica, the largest leatherback nesting beach in the eastern Pacific, with colleagues and Drexel students, for 22 years.
Poaching of turtle eggs was a major cause of the initial decline, and was once such a widespread problem that virtually no turtle hatchlings would survive at Playa Grande. Spotila and colleagues worked with the local authorities in Costa Rica to protect the leatherbacks’ nesting beaches so that turtle nests can hatch in safety. By catch of juvenile and adult turtles in fishing operations in the eastern Pacific remains a threat.
For the population to recover successfully, Spotila said, “the challenge is to produce as many good hatchlings as possible. That requires us to be hands-on and manipulate the beach to make sure that happens.”
Spotila’s research team is already investigating methods such as watering and shading turtle nests that could mitigate the impact of hot, dry beach conditions on hatching success.
Link to this Nature Climate Change study: http://dx.doi.org/10.1038/NCLIMATE1582
Link to recent news release about a related study by this research team in PLoS ONE: http://www.drexel.edu/now/news-media/releases/archive/2012/May/El-Nino-Climate-Change-Threaten-Leatherback-Sea-Turtles/
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Maybe this is a bigger problem? From Wikipedia:
Asian exploitation of turtle nests has been cited as the most significant factor for the species’ global population decline. In Southeast Asia, egg harvesting in countries such as Thailand and Malaysia has led to a near-total collapse of local nesting populations.[62] In Malaysia, where the turtle is practically locally extinct, the eggs are considered a delicacy.[63] In the Caribbean, some cultures consider the eggs to be aphrodisiacs.
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“We used three models of this leatherback population to construct a climate-forced population dynamics model.
It’s turtles all the way down then
I watched giant turtles on a beach in Masira Island, Oman, dig their egg holes, lay about 100 eggs, fill in the hole and struggle back to the sea and all digging done with their back flippers. I even watched the young by the hundred dig themselves out of their holes and aim for the sea. All this at temperatures higher than those leatherbacks endure.
These conservationists forget that extinction is the ultimate fate of all species.
“We need to change fishing practices that kill turtles at sea, intervene to cool the beach to save the developing eggs and find a way to stop global warming.”
How about those mist sprayers they use in Disney World to cool the people waiting in line for Pirates of The Carribean?
What part of global warming theory is suppose increase the temperature of sand?
There is still plenty of good cash in the AGW scare bucket for ‘research’ even if the political will has gone out of its sails , its still seem to be the case that no matter how poor the ‘science’ you can always get funded if you produce the ‘right results ‘ to support the ’cause’
And it its meaningless models all the way with a ton of speculation throw in and science by press release , they your merely following what is clear the standard methodology for ‘climate science’
Will the rest of the scientific establishment realize why there silence over such ‘games ‘ causes science in general to look like a joke to the people , or are their ivory towers so high they simple can’t see understand why the see no evil , hear no evil , speak no evil of your fellow ‘scientists’ no matter what they do is a bad idea ?
Blaming every possible catastrophe and every “extinction” on CAGW is really getting a bit old. It also means money is wasted.
It is about time true environmentalists started shouting this crap down
The temperature of beach sand is most largely dependent on the intensity of solar radiation of the moment. Surely this should be fundamental for the folk of Drexel University. Solar radiation passes through the atmosphere at light-speed and impacts the surface of the sand. At noon on a bright and clear day that energy-exchange will pump up the temperature of the sand surface enormously. It will fry the soles of your feet. Some of that newly-acquired heat will conduct downward into the body of the sand, while the greater part will add temperature to the layer of contacting air that makes its way across the surface of the beach. It is probably largely in order to avoid getting their flippers and egg-laying apparatus scorched that turtles, in their wisdom, beach at night to conduct their egg-laying activities. Any 0,8K shift of the mean atmospheric will have no bearing worthy of mention on this overall -process. But, to have need to explain this process to the good folk of Drexel University… words fail!
My kin in Key West did more damage to the ickel turtles 100 years ago than any warmer can imagine. They hunted the suckers down and ate or sold them. Tasty too. Recipes on request.
The real endangered species are the Climate Scientists. With the lack of warming, the lack of sea level rise and the lack of any credibility in their predictions… surely we’ll see them go extinct in our lifetime.
I thought that most of the warmiing was projected to be nearer the poles.
How ever did they cool the beaches during the holocene climate optimum? Do all the beaches where leatherback turtles lay their eggs have the same temperature? We need to dig deeper.
“In 1990, there were 1,500 turtles nesting on the Playa Grande beach,” said Dr. James Spotila, the Betz Chair Professor of Environmental Science in the College of Arts and Sciences at Drexel. “Now, there are 30 to 40 nesting females per season.”
That is, numbers have fallen by 97-98 per cent over 22 years in which temperature rise has been modest. If anyone is seriously concerned about the turtle population, possible warming by 2100 is hardly a major issue. If the issues that caused the decline are not addressed, they will be soon gone whatever the temperature.
Well we are moving beyond cuddly looking polar bears but it is still designed to be an appeal to emotion. You humans must change your behaviors because of this possibility we are modelling. I mean look at that raised head. One of the primary elementary science curricula used in the US is designed to create just this kind of emotional bonding with cute creatures. The emotions are there at an unconscious level ready to respond to an future marketing campaign on danger.
It helps that the sea turtles only tend to be seen at times few people are on the beach. And that’s the reality even when the population is healthy. The child and then the adult though are primed to believe they are not seeing sea turtles because they are already endangered. Must change behaviors NOW if anyone is to ever see a sea turtle again.
If you really want to see one, change your behavior to walking on the beach at dusk and predawn. Instead of pushing for a return to windmills.
A bigger danger to sea turtles is artificial lighting. Turtle hatchlings are attracted to light and can wander inland towards homes and street lighting instead of the sea. Coastal Florida has regulations for light abatement on beaches. Also, as with TS Debbie, coastal erosion from storms can wipe out nests.
This posting by Wills adds some proper science as to why turtles choose to lay their eggs in sand ……..they have evolved in this way because:-
Time Lags in the Climate System
Posted on June 18, 2012 in WUWT by Willis Eschenbach
Guest Post by Willis Eschenbach
Did you ever sit on a hot sand beach and dig your hand down into the sand? You don’t have to dig very far before you get to cool sand … but even though it’s nice and cool a few handwidths down, the fact that it is cool doesn’t matter at all to either the temperature of your feet or to the temperature of the air.
………………………………………………………………………………………
PS—To return one final time to the sandy beach, my natural habitat, the diffusivity of dry sand is on the order of a = 1.3E-7 m^2 per second, with t = 86400 seconds for the cycle length (one day). Using those variables in Equation 2, we find that the depth z required to get only half the temperature swing of the surface sand is only 4 centimeters, or about an inch and a half …
Soooooo….. People were EATING the turtle eggs. Year after year. The turtles were very few in number because of this. Recently, people were prevented from eating the eggs. And so the turtles have recovered a bit. BUT! Global Warming! Hot sand! Oh noes! Send money! Spread the money on the sand! Hurray! See? The sand is cool! Now the turtles are saved again!
Human predation seems to be the major cause. That we have some ability to influence. Yet, these folks seem to use the decline as an excuse for funding/publications in their field. I should be surprised?
“…New research SUGGESTS that climate change COULD exacerbate existing threats and NEARLY wipe out the population…”
“…NEARLY wipe out the population…” Extinction means ALL of them will be gone. They added this so that just in case one turtle makes it to Jan 1st, 2100, they’ll be right.
Well, I’ve seen experimentally recorded data that disproves their model. The very famous and scientifically and intellectually honest Jack Cousteau (late) and also his son, have filmed (or videotaped), live and very uncooked turtles being snatched off the beaches by those evil Frigate birds; by the tens of thousands. Even crabs have been coming out of those very same sand Webers, and hauling those turtles back down to where they can cook them some more.
I don’t believe Jack would ever have lied to us with photo-shopped film of something they didn’t actually see happen; or pull tricks, like killing fish to goad sharks into a feeding frenzy, so he could film it for us American saps, so we’d pay for him to have his fun.
So I say they should put a bounty on Frigate birds, and sand crabs too; it is they who (what/that) are (is) killing all the little turtles; also they should stop people from making film of it for profit.
“The researchers applied Saba’s combined model of these population dynamics to seven climate model projections assessed by the Intergovernmental Panel on Climate Change (IPCC)”
Models? Garbage in = Garbage out. As soon as I hear the word “model” in one of these scare monger reports, all the rest is just noise.
Okay. How long will that quote from Wikipedia remain on their site?
I wouldn’t be surprised if the turtles can tell how hot it is and adjust the depth a couple of inches to accommodate, after all the warmest part of this interglacial is long over, so they’ve had several thousand years to practice.
As you say these turtles survived the Holocene Optimum _and_ the Eemian which was hotter. It is obvious that none of these researchers or their professors at Drexel are obviously ignorant of the evolution of turtles more than 200 million years ago.
It is worrying that a university that says “The Academy of Natural Sciences of Drexel University is America’s oldest natural history museum and a world leader in biodiversity and environmental research. For 200 years, the Academy has encouraged and cultivated the sciences, exploration of biodiversity and sharing discoveries with the public.” can display such ignorance. Perhaps they are putting too much into the Agenda21 ‘biodiversity’ meme and the ‘community outreach’ and too little into actually learning biology.
Don’t turtles dig their way down until they find sand at the right dampness and temperature? Be interesting to compare laying depths for various species at various incubating sites with ambient temperatures for the incubating season. I’m not a scientist, just saying.
Anyone who has had to scamper across a hot beach when they forgot their flip-flops, running from shady spot to shady spot … or digging the feet underneath …. knows more about the thermodynamic properties of sand than these chumps ever will.
Their numbers are wrong. It could be a decline of 4.72% per decade or 8.6% per year but not 3.3% or 7% per decade. No no no. My models are conclusive, and I used four of them. And no, you can’t see the data or the models. Later, I’ll model something else that might happen (but won’t).
Turtles, by the way, have no knowledge that the temperature of sand is dependent on depth. They have asbestos feet with no sensory organs.
Anyway, the surface of the sand will be hard and glassy, so they won’t be able to dig through anyway.
Tired of this yet?
Gerry