Some social media users are claiming that rising temperatures are affecting the ratio of male to female sea turtles in Florida. A post on Twitter claims that every sea turtle born in Florida this year is female, while the state has another record-setting scorcher of a summer.
If true, this could be a game-changer for the sea turtle population around the globe. But, is this claim legit? Here’s how we fact-checked it.
Start with a keyword search
This tweet also includes a photo of what looks like an article headline and subhead, so let’s start off with a keyword search to see what reputable sources have been saying about the sex ratios of turtle hatchlings in Florida this year.
We searched for “Florida turtles” + “all female” + “rising temperatures,” and a lot of articles from credible sources popped up with headlines that appear to match the text of the tweet. We clicked on an article from Reuters titled “Hotter summers mean Florida’s turtles are mostly born female.”
The first thing we noticed was that the headline says “mostly” and not “all.” It’s always important to read beyond the headline, so let’s check out what the rest of the article says.
Read past the headline
The reporter behind the Reuters article talked to scientists at the Turtle Hospital in Marathon, a city in the Florida Keys. Officials there confirmed that their researchers had been finding only female turtles in the past four years. The past four summers have also been notably hotter than usual, even by Florida’s standards, which plays a role in the determination of the sex of turtle hatchlings.
The Reuters article cites information from the National Oceanographic Atmospheric Administration, or NOAA. So I went right to the source, which is known as “reading upstream.” That’s the best technique to use when you’re reading an article or watching a video and the creator provides links to their evidence. On its “Ocean Facts” webpage, NOAA states that the sex of most sea turtles and alligators depends on the temperature of the developing eggs as they are incubated in the sand.
But, back to the article. While the researchers in the Florida Keys did find only female turtle hatchlings, it’s important to note that the study is only looking at one area of Florida. Since the state of Florida has some of the biggest nesting populations along the Gulf of Mexico, we knew we needed to get a better understanding of the full picture.
So, we reached out to some other scientists at the Mote Marine Laboratory & Aquarium in Sarasota. They told us that the claim that all turtles are being born female is “not nuanced enough, as it only takes into account a study in a specific area.”
The weather in Sarasota is slightly cooler, and researchers there have found some male turtle hatchlings. Jake Lasala, a researcher at Mote’s Sea Turtle Conservation & Research Program, confirmed that they found male turtle hatchlings at “at least two” of the nests that Mote monitors.
Lasala also provided important context: Sex bias has been observed in Florida turtle hatchlings since the ’90s. Lasala also referred us to this study out of Australia, which found that there was a female bias amongst not only turtle hatchlings, but also with juveniles.
But that doesn’t mean that the turtles in Florida aren’t under threat from rising temperatures. Lasala stressed that the turtle populations in Florida are skewing female, which he said is definitely a problem for sea turtle populations long term.
“We have had female biased populations for a really long time,” Lasala said. “However, with increased temperatures globally, we are looking at places other than just Florida and we are seeing the extent of that sex ratio skew actually to be more prevalent.”
Lasala clarified that it’s not always a bad thing to have a biased sex ratio — in slightly female biased sex ratio, there will likely be more offsping.
“But, in an extremely biased sex ratio, you could lose your genetic diversity and you could not have as many males to be able to continue having offspring,” Lasala explained. “We’re concerned that that’s the point that we’re getting to, but we’re not there yet.”
In order to monitor conditions on beaches with known turtle nests, Lasala and his team will be placing temperature sensors in the sand in order to take stock of temperatures.
We rate this claim “needs context.” While some scientists have only been finding female turtle hatchlings and turtle populations have been skewing female — which scientists are attributing to rising temperatures — it’s not correct to say that all the turtles that hatched in Florida this year have been female.
It can be really tempting to quickly reshare things you see on social media, especially when it’s about something you really care about – like the environment and animals. It’s always important to verify information before reposting on social media to make sure that you aren’t accidentally sharing misinformation.