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Earth Australia Science

Sea Turtles Under Threat As Climate Change Turns Most Babies Female (futurism.com) 177

Posted by BeauHD from the existential-threats dept.
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.
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Sea Turtles Under Threat As Climate Change Turns Most Babies Female More

Sea Turtles Under Threat As Climate Change Turns Most Babies Female

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  • Yeah but (Score:5, Funny)

    by SCVonSteroids ( 2816091 ) on Friday January 12, 2018 @07:36AM (#55913845)

    Imagine being a part of THIS 1%.
    Women. Everywhere.

    I'm starting to like this climate change thing.

    • Be careful . . . it might not work out as you plan . . .

      "Death! Death by Snu-snu!"

      • Be careful . . . it might not work out as you plan . . .

        "Death! Death by Snu-snu!"

        Beats getting hit by a bus.....

        To quote my old friend Richard Pryor:

        "Cause if I had a choice, now, men, you know the truth when I tell you if you had a choice between dying in some pussy or getting hit by a bus, which line would you be in? I know which line I'm gonna be in. I'm gonna be in that long mother fucker, jack. "

        Damn...I miss him and old George Carlin...back when comedians were funny, not afraid to say anyt

    • Re: (Score:2)

      by umghhh ( 965931 )
      single male in a female society - that means there are no male role models and you are just a strange female so nobody likes you.
      Looks like a goal of #metoo-ers.

      • Re: (Score:2)

        by tsa ( 15680 )

        This.
        When I was in high school I was in a class with 27 females and three males, myself included. Quiet but strange.

        • Re: (Score:1)

          by Anonymous Coward
          I don't believe you. A class that was 90% female was quiet? ;P

      • Re: (Score:1, Funny)

        by Anonymous Coward

        Imagine having a whole planet of people claiming you raped them.

        • Re: (Score:1)

          by Anonymous Coward

          Imagine having a whole planet of people claiming you raped them.

          Harvey Weinstein can picture that.

    • Re: (Score:2)

      by kackle ( 910159 )

      Imagine being a part of THIS 1%. Women. Everywhere.

      I'm starting to like this climate change thing.

      Or "how he stopped worrying..."

    • have you seen a male sea turtles honey-do list? Their weekends are spend mowing lawns, picking up dry cleaning and fixing fences.

    • "Imagine being a part of THIS 1%.
      Women. Everywhere."

      That's exactly why they do it. The conditions are good and since one male can fertilize dozens of females, it's the way to go if you want to multiply your genes real fast.

    • Re: (Score:2)

      by antdude ( 79039 )

      But you will be too old or dead for them. ;)

  • Denial (Score:3, Insightful)

    by The Evil Atheist ( 2484676 ) on Friday January 12, 2018 @07:36AM (#55913847)
    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?
    • Better yet, is Jim Inhofe (Fuckhofe) going to turn up to the Senate and throw a male turtle down on the floor?

    • Re: (Score:2, Insightful)

      by Opportunist ( 166417 )

      It's the damn feminists and SJWs and that they only make the male turtles identify as female.

      • Re: (Score:2, Insightful)

        by dwillden ( 521345 )
        Or did the researchers just assume the genders of all the turtles? What if most northern turtles are more liberal and prefer to identify as female until breeding season? Whereas the more conservative southern turtles don't believe in such gender fluidity? ;)

    • If you know anything about reptiles you'd know this happens in cycles to take advantage of food surpluses. Reptile eggs tend to be female when incubated at higher temperatures and male when at lower temperatures. Meanwhile, one male can impregnate many females. Generally speaking a warmer incubation temperature correlates with a warmer climate and in turn greater food supplies as it means more algae growth, more baitfish consuming the algae, etc. This means in a few years when the current clutches of se

      • The "O! My god! The planet is overpopulated!" freaks would argue otherwise. Lets reduce females to 10% of the population ...

    • Re: (Score:2)

      by DeBaas ( 470886 )

      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?

      It's all the Soy milk that ends up in the water. Let's blame the hipsters!

    • Yeah I mean it couldn't be something like Estrogen Analogs in the water from decaying plastics could it ?

      https://www.newscientist.com/a... [newscientist.com]

    • I would like to see what they historical population ratio has been over the years, and if there is a trend, an anomaly, or if this is in the band of typical. They apparently compared two different regions and assumed they should have the same ratio. They also assume that they know which turtles came from which region

      Here, for the first time, we use genetic markers and a mixed-stock analysis (MSA), combined with sex determination through laparoscopy and endocrinology, to link male and female green turtles foraging in the Great Barrier Reef (GBR) to the nesting beach from which they hatched.

      But they have no way to prove if this method is accurate because they are not allowed to disturb the hatch lings.

      I don't question AGW, but I do question any conclusions drawn from this study

      • I would like to see what they historical population ratio has been over the years, and if there is a trend, an anomaly, or if this is in the band of typical.

        So would the scientists.

        In truth, the only way to determine if this is a problem is to study the species and if they go extinct, then determine why.

        Typically, an imbalance at this level puts a species at risk by virtue of the one gender having to be genetically perfect. Get a few males with some messed up chromosomes or sterile, and that number starts ticking even lower.

        Certainly at the 1 percent male level, most females will not reproduce.

        Anyhow, we learn about these things by studying them.

        • I would like to see what they historical population ratio has been over the years, and if there is a trend, an anomaly, or if this is in the band of typical.

          So would the scientists.

          In truth, the only way to determine if this is a problem is to study the species and if they go extinct, then determine why.

          Incorrect. They can monitor population trends and cycles, then determine when things are out of the normal range.

          Certainly at the 1 percent male level, most females will not reproduce.

          "Most" females may not need to reproduce in a given year to maintain the population. What is the typical ratio range? That information is not provided. Also note that there are more than 1 percent males in the total population. They are limiting the low male ration to only those they believe were from one breeding area.

          There is clearly not enough information to draw any conclusion. But don't l

          • I would like to see what they historical population ratio has been over the years, and if there is a trend, an anomaly, or if this is in the band of typical.

            So would the scientists.

            In truth, the only way to determine if this is a problem is to study the species and if they go extinct, then determine why.

            Incorrect. They can monitor population trends and cycles, then determine when things are out of the normal range.

            Define "normal range: Especially in a long living animal like a sea turtle. http://www.fpir.noaa.gov/PRD/p... [noaa.gov] Then there is that "historical" bit in the mix. This is where problems occur. You hit on it yourself, so I wouldn't be in such a hurry to diasagree with me agreeing with you.

            Animal species populations fluctuate all the time. Sometimes wildly. Chipmunks are a good example, and one that most of us could verify. Some years there are dozens running around my back yard, then a year later, almost none.

            • I was pointing out that there are no conclusions that can be drawn, you are arguing with me so I assume you think some can be drawn.

              So, what have the population ratios from that breeding ground been historically? You seem to think we have the data even though the study itself indicates we don't.
    • Comment removed based on user account deletion

    • Really?
      WRT the article it seems reasonable to ask: why has nature evolved the observed gender bias/temp correlation? does the gender bias plateau? is the gender bias 'fixed' or will it too evolve to the change? Those questions are not answered so a prediction seems more like a linear guess than anything else.
      For example:
      If you took a sampling of domesticated chickens from chicken factories over the past three decades you would have noticed a staggering increase in breast size that alarmingly coincides w

  • 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,

  • ORGY (Score:1)

    by stooo ( 2202012 )

    (male) Ninja turtles have a mega orgy

  • Why is this a problem? (Score:5, Insightful)

    by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Friday January 12, 2018 @07:41AM (#55913865) Homepage Journal

    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.

    • It's a problem because the aquatic ecosystems have been balanced carefully over millions of years, numnuts. You know what ecosystems are, right? Nature cannot correct fast enough to keep up with the destruction that we're imparting on it. Just because it doesn't affect your immediate ability to stuff your fat face with potato chips while you do nothing productive for the world doesn't mean it's not important.
      • Stupidest comment of the day. Ecosystems are not "balanced carefully over millions of years". Shit happens, and life adapts.

      • Do you understand that what we are seeing IS that balance in action?

        > Jellyfish populations UP due to warmer climate.
        > Sea turtles giving birth to more females to enable the population of sea turtles to increase in correlation to the increased abundance of their primary food source.

        This observation is proof that the aquatic ecosystem balance is in fact WORKING, not that it is breaking.

    • "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. "

      This statement demonstrates an incredible amount of ignorance. A huge number of animals on earth do NOT engage in polymagous behavior. Frankly, it is not true that 'one male can service many females' for many many animals, for a variety of reasons.

      While it is true that physical possibility exists for most

    • Turtles actually spawn on the same beach where they were hatched.

    • Re: (Score:2)

      by pots ( 5047349 )

      what else changes?

      The entire turtle population in the north part of the reef goes extinct, the turtle population in the southern part of the reef is the only one left. That's a change.

      You seem to be suggesting that the northern turtles will just know that their babies (who they never see) are being born with skewed genders, and that they just need to move south to solve this problem. South, into... uninhabited territory? No, the south already has as many turtles as it can handle (not a huge number).

      Also, even if a sing

  • 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
    • Could be a question of time constants. Do you adapt before it wipes you out?

    • 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.

    • Re: (Score:1)

      by Anonymous Coward

      It depends. If the change occurs on a small scale of time nearly the only chance is that enough individuals have got already the traits to reproduce in a higher temperature setting. The individuals with this trait will have a reproductive advantage and the gene will propagate (You cannot count on a new mutation, the timescale is too short). But there is a lot of BUTs :

      - if the population is there for a long time in a stable environment the genetic diversity is low by genetic drift, the chance of having the

    • Re:Won't this self correct? (Score:4, Interesting)

      by Gilgaron ( 575091 ) on Friday January 12, 2018 @10:38AM (#55914515)
      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.

    • Green sea turtles take between twenty and fifty years to reach sexual maturity.

      A 2C change over 100,000 years -- roughly normal for geologic history -- would almost certainly produce the kind of adaptation you are envisioning. But speed that up by a factor of one thousand and you've got a different picture. 100 years represents between two and five generations for green sea turtles. A century isn't long enough for polygenetic adaptation to this magnitude of change; the only possibility of population survi

      • A 2C change over 100,000 years -- roughly normal for geologic history -- would almost certainly produce the kind of adaptation you are envisioning.

        According to this article [newscientist.com] Ice Ages turn on a LOT faster than this. The article claims that it was originally thought it took a decade or two, now they have it down to a matter of months (if correct). Human-induced climate change seems to be on the order of decades.

    • Won't the males who do survive produce offspring more likely to be male in higher temperatures.

      It should do since turtles have been around for the past 200+ million years which has included more than a few ice ages and warmer periods. Human-induced climate change is a serious issue but half-true stories like this designed to imply a looming disaster just play right into the hands of the denialists.

  • The rate of population growth is proportional to the size of the female population, not the male. One male can fertilize multiple females. Consequently, males are not as important to sustaining or growing the population as females are. While an entirely female turtle population would be bad, the rate of population growth is maximized at some point above 50% female. The more often turtles are to encounter each other during mating season, the fewer males are required to maximize population growth. So if

    • "Global Warming Causes Sea Turtle Population Explosion"

    • The rate of population growth is proportional to the size of the female population, not the male. One male can fertilize multiple females.

      The paper actually addresses this point, and says we don't know if the males can take up the slack. But that hammers home the point that the headline is bullshit. We don't actually know if they are under threat. This might actually lead to larger populations. We don't know, which is why this story is FUD when presented with this headline.

      • Let's see, just put aside monogamy for a moment. How many women do you think you could fertilize in a year.

        Let's really up the ante. Lets say 99% of the male population die off, and there are now a 100 women for every one man. And well, a lot of them, a really, really a lot of them want to have both sex and babies. So they're at your door lining up...

        Well, if timed to ovulation (which most other species send signals to alert so mating occurs then), then they could fertilize quite a few.

        I wager that I pe

    • Stop using your brain, reasonable discourse, logic, and science to make arguments against Global Warming. You're arguing from a scientific standpoint against a religious dogma. ;-)

  • Reptiles have been around for a loooong time. They've adapted to the most effective strategy.

    Warmer temperatures means more food. Females produce more eggs. One male can fertilize a LOT of eggs.

    This produces more turtles to eat the food produced by warmer temperatures

    So the question is "Why is what's happening in North Australia a problem?"

    • So the question is "Why is what's happening in North Australia a problem?"

      Is the answer "Teenage Mutant Ninja Turtles?"

  • How many females eggs can a single male fertilize? It sounds like the previous "balanced" picture was 70% females anyways, now 86-99%, if the males can keep up fertilizing, wouldn't that mean that the "threat" they are under is exploding population (too many turtle babies)? Does the male turtle somehow take car of the babies and if so, how many can it take care of (even if not all, with more babies it still leaves a much more effective natural selection process)?

  • Suppose you've got a species where the female to male ratio is determined by temperature like sea turtles. And suppose that a higher temperature means more females.

    Since only females can lay eggs and female egg laying is the bottleneck in population growth it seems very likely that more females means more offspring.

    So this mechanism essentially says 'if the water temperature increases, increase the number of turtles'.

    Which is not actually bad decision - warmer waters have more sea life, i.e. they can feed m

  • And it isn't like they have been around for hundreds of millions of years and responded to climate changes all along the way. If this is the way they survive such changes perhaps the scientists should try to understand why this allows them to survive.

    • Re:Yah, right (Score:5, Informative)

      by TimothyHollins ( 4720957 ) on Friday January 12, 2018 @08:39AM (#55914063)

      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/ [xkcd.com]

      • Re: (Score:1)

        by Anonymous Coward

        You say "never", and then refer to a timeline that only shows the last few thousand years. If you want to convince your opponent, please don't use arguments that even your own side can see through...

        Besides, I'm pretty sure the quickest climate change (and one of the most destructive) - though that was cooling, not warming - was the one caused by the meteor and following ash cloud that killed the dinosaurs.

        Years of darkness will decrease temperatures very quickly.

      • What happened to the Medieval Warm period in that graph? Oh they say it only happened in Europe. Fake news!

        https://en.wikipedia.org/wiki/... [wikipedia.org]

        There's a whole bunch of temperature reconstructions here and all of them show both a Medieval Warm period and a Little Ice Age

        https://wattsupwiththat.com/pa... [wattsupwiththat.com]

  • I am sure the male turtles are happy about this

  • Re-run the survey in 5 years; el Nino just ended (Score:5, Insightful)

    by davide marney ( 231845 ) on Friday January 12, 2018 @08:52AM (#55914099) Journal

    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.

  • 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,...

    Interesting; what evolutionary ben

    • Well, if you have 99% of the population female and 1% male, unless they are monogamous, you can have 99% of the population procreating. It seems like a way to ensure lots of new baby turtles...

      • Re: (Score:2)

        by Eloking ( 877834 )

        Well, if you have 99% of the population female and 1% male, unless they are monogamous, you can have 99% of the population procreating. It seems like a way to ensure lots of new baby turtles...

        If this specie of turtle is independant and meeting between turtle isn't frequent, it could backfire. Not every male animal are like rabbit.

  • If the slight variations in temperature make 99% of hatching (identify as) female, the entire species would've died out through Ice Age, when 99% of them became males instead...

    The wildest accusations made by the believers of the Global Warming is that it is only a few degrees warmer now than it was 100 years ago. If that's enough to threaten the turtles today, how did they survive the ice ages of the past?

  • Let's use our heads.. (Score:3)

    by PortHaven ( 242123 ) on Friday January 12, 2018 @11:00AM (#55914647) Homepage

    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... [isciencetimes.com]

    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!!!

    ***
    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/... [yale.edu]

    https://www.realnatural.org/dy... [realnatural.org]

    ***
    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 are adaptable. (Score:3)

    by PortHaven ( 242123 ) on Friday January 12, 2018 @11:29AM (#55914827) Homepage

    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.

  • 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.

    Coincidentally, I've got 99 problems.

  • Because they use a technique of determining sex ratios WITHOUT HAVING TO KILL BABY TURTLES! Imagine that, they killed turtles in earlier studies to determine what the sex ratio of the hatchlings was. Mind boggling.

    "There are several challenges with directly estimating sex ratio at rookeries. At present, hatchling sex determination can be achieved reliably through histological examination of the gonads, but the sacrifice of live hatchlings carries ethical implications, and there is possible sampling bias i

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