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Sea Turtles Under Threat As Climate Change Turns Most Babies Female (futurism.com)
A new study published in the journal Current Biology found that as much as 99 percent of baby green sea turtles in warm equatorial regions are being born female. "The study took a look at turtle populations at nesting sites at Raine Island and Moulter Cay in the northern Great Barrier Reef, an area plagued with unprecedented levels of coral bleaching from high temperatures," reports Futurism. "The researchers compared these populations with sea turtles living at sites in the cooler south." From the report: Using a new, non-invasive hormone test, the researchers from the U.S. National Oceanic and Atmospheric Administration (NOAA) Fisheries Department and the Queensland Department of Environment and Heritage Protection found that while 65 -69 percent of the turtles from the southern region were female, between 86.8 and 99.8 of turtles tested in the northern region were female, depending on age. The sex of green sea turtles, along with some other species of turtles, crocodiles, and alligators, is not regulated by the introduction of sex chromosomes at key points during early development, as seen in humans and other mammals. Their sex is actually influenced by the temperature at which the eggs are incubated, with warmer temperatures more likely to lead to females. The difference between predominately male and predominately female hatchlings is only a few degrees, such as that formerly found between the cool, damp bottom of a sandy sea turtle nest and the sun-warmed top. The ages of the female turtles in the north suggest that this population has experienced temperatures that cause this imbalance since at least the 1990s. Given that the warmer temperatures seen in northern Australia have been distributed around the globe, experts predict that other sea turtle populations in warm regions are also following the same trend.
Imagine being a part of THIS 1%.
Women. Everywhere.
I'm starting to like this climate change thing.
I tend to rant.
I wonder what ad-hoc excuse the denialists will come up with this time. A mythical "pause" in the rate of increase of female sea turtles? Sea turtles that live in a specific layer of the upper atmosphere that doesn't fit the trend exactly? Sun spot effects on sea turtle embryonic development? They found a male sea turtle once, so the trend doesn't exist?
Those who do not learn from commit history are doomed to regress it.
With a 99% female population, I fear the remaining males will die from nagging.
Hmm, maybe there's an Occupy Wall street joke in there somewhere,
The abstract does not mention why this might be a problem. It says "results show a moderate female sex bias (65%â"69% female) in turtles originating from the cooler southern GBR nesting beaches" which indicates that there are southern beaches which are cooler. So uh, more females born, more eggs laid, more offspring, turtles spawn where turtles can spawn, and the range where they spawn changes but... what else changes?
I'm willing to accept that this might lead to too few males for a viable population, if somehow turtles are different from basically any other animal on earth, and one male can't service many females. However, the paper also says "Although increased breeding frequency, as well as polygynous behavior of male turtles, may help mitigate skewing offspring sex ratio [39], it is unknown how many (or what minimum proportion of) males is sufficient to sustain sea turtle populations."
IOW, your headline is FUD. Slashdot as usual.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Climate changes have never been even remotely as quick (i.e. destructive) as they are now. For evolutionary adaptation, multiple generations are needed, and the current changes are just too damn fast to adapt to. For a timeline reference, please see https://xkcd.com/1732/
Won't the males who do survive produce offspring more likely to be male in higher temperatures. I would expect a dip in pupulation (as 1% males can't fertilise all the females) but in the long run it would correct
We might know that if the study showed a historical ration record, but unfortunately it is just a one time snapshot and therefore tells us nothing about how the population ration trends or cycles.
A cyclic warm period in that exact location just ended. Re-run the study in 5 years and let's see what happens. You can't predict a trend from a single data point.
"We receive as friendly that which agrees with, we resist with dislike that which opposes us" - Faraday
Comment removed based on user account deletion
Yes! But... fragmentation of populations and other stresses put on wild populations by human action make it harder for them. So, if the whole coast was fine to use, the turtles would surely adapt (they've made it through some rough times like the Cretaceous extinction, after all). With less coast to use due to humans, it is harder to be sure.
Sea turtles under threat as majority being born are female....
THIS IS PROBABLY THE BEST NEWS WE'VE HEARD ABOUT SEA TURTLES IN YEARS!!!!
Why?
Okay, let's just use our brains. And for a moment, in order to simplify, I am going to use humans in order to reduce the variable set (as sea turtles lay batches of eggs).
Lets say there are a 100 people. What is the maximum number of new babies that can be born?
Let's say, it was a 50/50 population of male/female. The maximum with typical births is 50 babies born.
The maximum births would be achieved by a population of 99 females, and 1 male. Yes, a single fertile male human being could fertilize 99 human females (and likely enjoy it too). Giving 99 new babies, though the human race would suffer from genetic diversity issues.
The nightmare scenario is not more females being born, but more males. If we had 99 males, and only 1 female...the birth rate is 1.
What this report really points too, is a potential rebound for sea turtles. If we have 10 to 90 ration, we are looking at potentially seeing a lot lot more sea turtles. Why might this be? Okay, they blame the warmer sea temps. And they may in fact be a factor, but lets look at the standard life equation. Population increases occur when there is habitat and food. Presently, there is talk about a increase in jellyfish populations, with some regions seeing a 40%-60% increase.
http://www.isciencetimes.com/a...
This means more availability of sea turtles prime food. Okay, so now consider the correlation. More food, turtles not having to range as far, so they're staying in the warmer regions. Big glut of jellyfish, saw one article exclaim that global warming was going to cause jellyfish to take over the ocean. So now, one of the prime predators of jellyfish is setting the stage to take advantage of this jellyfish bloom.
THIS IS GREAT NEWS!!!
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As for the coral reef die offs/bleaching. Yes, that gets blamed on global warming. However, there are a number of scientists who have said that is a mere secondary issue. The primary cause is extremely high levels of agricultural pesticides, (designed to kill arthropods and invertebrates), that are affecting the reefs - particularly off the coast of Australia.
Similar to the bee die offs, which were repeatedly blamed on global warming, until strong evidence began showing that pesticides, such as nicotides and others were largely responsible. And with both colonies (bees and coral) what we see is a conjunction of issues. Pesticides weaken the species, which become more susceptible to illnesses (parasites particularly with bees, and a herpes virus with coral reefs).
http://e360.yale.edu/features/...
https://www.realnatural.org/dy...
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IF YOU CARE ABOUT THE ENVIRONMENT, you need to STFU about global warming. Because whether it is occurring or not is irrelevant. (Trust me, the earth has been much warmer, life thrived, vegetation increased, deserts shrunk, granted human coastal villages and cities may be under water...but humans adapt.) However, global warming is being used to mask the multitude of real and threatening environmental problems.
> Deforestation used to be a topic. We've not stopped cutting down rainforests, nor looked at using rapid renewables such as hemp for paper or bamboo to replace our 2x4's.
> Pesticides and herbicides used to be a topic. Now, all the die off of species are blamed on global warming. Some of these chemicals are genetically destructive and can persist for decades, centuries, perhaps even milleniums.
> We used to talk about waste, landfills, etc. But we don't...we only talk about global warming.
Global warmin
Sea turtles have been around for hundreds of millions of years. In fact, they reached gigantic proportions during the Cretaceous period. Perhaps because of abundant food supply. I wager jellyfish thrived in the oceans when the equatorial surface water temperature reached a 108 F.
Yes you read that correctly, sea turtles existed at a time when the water temperature peaked at 108 F. Presently, the peak for equatorial surface water appears to be around 86 F. So when we exclaim that one or two degree change is going to cause destruction of the sea turtle population, while historical science shows they thrived at temperatures that were 20 degrees warmer. You kind of look like an idiot.