In Florida, the population numbers of several sea turtle species are improving, including green sea turtles; but conservation groups are suing the Trump administration for not doing enough to protect green sea turtle habitat.
Jaclyn Lopez is Florida director with the Center for Biological Diversity, one of the groups that filed a lawsuit last week.
“We filed a lawsuit to try to compel the two agencies that manage our sea turtles, the Fish and Wildlife Service and National Marine Fisheries Service to designate critical habitats. Critical habitats are the areas of habitat that are necessary for the species’ survival. And includes the nesting beaches and offshore areas.”
SK: Where in Florida are places that need protection?
“Green sea turtles nest quite successfully in Florida. We have nesting sea turtles in nearly every coastal county in Florida. With the heaviest nesting just south of us, through Sarasota all the way down to Lee County. And on the opposite coast in that same area. So, those are the densest concentration of green sea turtles. We also have green sea turtles that are off of our coasts.
“So, we don’t have a proposal yet from the agencies as to where they consider the most important nesting beaches or offshore areas to be. And that’s what we’re hoping to get them to do, is that first step in determining where the necessary habitats are.”
SK: What are the threats that green sea turtles are facing?
“In nesting beaches, the threats that our green sea turtles — and actually, all of our sea turtles that nest on our shores — are facing, one of the historic impacts, are beach development. And one of the impacts there are the loss of dunes and protections that the dunes provide from things like even lighting. Which can disorient, especially, the hatchlings as they emerge from their nests and are trying to find a light that’s reflecting off the water. [Hatchlings] can get disoriented by lights from development from the roads. And dunes can protect from those. So, those are more, sort of, historic ongoing threats.
“But, now within the last decade or so we really been seeing accelerated sea-level rise at some of these beaches. And so, for example, on the east coast, we’re seeing more instances of tidal inundation of these nests. So, typically, when the sea turtles come to nest, they do it far enough up on the beach so that the nest itself won’t get inundated by water. [The nests] have to stay fairly dry for the sea turtles to hatch out of their eggs and successfully crawl back into the water. And if they do get inundated, then we see the hatchling survival rate really drop.
“With sea-level rise, we’re experiencing already increased inundation of the nests. And that’s just going to continue. And then, we’re also going to see, and have seen, a race to fortify our coasts with seawalls, with offshore breaks, with other hardening devices that can then impact the nesting beaches. By either creating accelerated erosion or sometimes even accretion in other areas. So, by interfering with the nesting through our adaptation to sea-level rise.”
SK: How has the warming of the oceans and of the atmosphere affected egg development in sea turtles?
“A really interesting development with sea turtles in Florida is we’re seeing near 100% of the hatchlings (are) female. And that’s because the sea turtle species that we have in Florida, their sex is temperature-dependent when they’re in their nests. So as temperatures rise, that determines, sort of turns on and off, whether they’re going to be male or female. When the temperatures rise they become female. And, already, we’re seeing near 100% of our hatchlings being entirely female.
“Which maybe on first blush might be a good thing because you only need one male to help with reproductive success of multiple females. But you still need some kind of ecological balance there. Especially when you take into account that the success rate of a hatchling reaching reproductive maturity, which for these sorts of sea turtles aren’t until they’re in their tens or teens, can be really great odds. Some people estimate it as 1 in 10,000. So out of one out of every 10,000 eggs that are laid, only one will reach reproductive maturity. And then, if you’re further reducing the odds of that being a male, then you’re going to start to see some significant population impacts in the next two decades.”
SK: Is there anything else that people should know about your lawsuit or about the population of sea turtles in Florida?
“Florida should be very proud of what we’ve done for sea turtles, to date. We’ve really helped to bring back sea turtles from a really bad place in their history. And especially green sea turtles have rebounded in their population. But the fight’s not over yet. Between sea level rise and the stresses imposed for the beaches and human effort to address sea-level rise. We need to really be putting all tools on the table, including mitigating greenhouse gases, just from the get-go. So not waiting until the greenhouse gasses are affecting climate change and that’s affecting sea level rise, but demanding action now from our government to set emissions reductions so that we’re not even getting to that point to begin with.”
Here’s a link to more WMNF stories about the environment.