I mentioned recently that elevated temperatures from climate could skew sea turtle sex ratios towards females. The featured news article highlights research which speculates that storm surges caused by increased hurricane (they call them cyclones in Austraila and India) intensity from climate change might lead to the flooding of green turtle nests in Florida, hastening their extinction. Why only the greens? Because they nest later than the other turtles and tend to be around during the height of the Atlantic hurricane season.
We know from previous research that loggerhead turtles have been nesting earlier because of elevated temperatures. Will the greens catch up. More pertinently, will there be enough survival of the early nesters of this generation to keep a viable population going while the whole population adapts? As with all climate change suspense thrillers, only time will tell… Depressing, at any rate.
More severe tropical cyclones expected as a result of climate change may lead to the extinction of the green sea turtle in some areas within 100 years, researchers say.
The cyclones are expected to threaten how well the turtles nest and hatch eggs, placing pressure on already endangered populations, some of which are also threatened by fish trawling.
Researchers including PhD candidate David Pike, from the School of Biological Sciences at the University of Sydney, report their findings online in the journal Oecologia.
The researchers studied more than 40,000 sea turtles nests on an uninhabited, 38 kilometre stretch of beach along the Atlantic coast of Florida from 1995 to the end of 2005.
Each night during this period researchers surveyed the beach for turtles emerging to lay eggs, or for tracks of turtles that had already deposited eggs.
The stretch of beach is home to the loggerhead, green, and leatherback sea turtles, which start nesting at the beginning in April and end in late September.
This nesting season largely coincides with region’s tropical storm season, which runs from June to November.
Leatherback turtles (Dermochelys coriacea) and, to a lesser degree, loggerhead turtles (Caretta caretta) get around this by nesting and hatching earlier.
Only nests laid late in the season are inundated with seawater during storm surges.
But green turtles (Chelonia mydas) nest last.
Their entire nesting season occurs during Florida’s tropical cyclone season, which means their nests and developing eggs are extremely vulnerable to being washed away and killed.
Researchers are concerned that increases in the severity of tropical cyclones in the future may cause green turtle nesting success to worsen.