Recovering sea turtle population to face challenges with climate change

Recovering sea turtle population to face challenges with climate change
Green sea turtles are recovering, but still face threats with climate change. (Image: NOAA Fisheries/Willem Staman)

HAWAII (HawaiiNewsNow) - While Hawaiian green sea turtles have been increasing their population for years, scientists are worried about the effects that climate change and sea level rise could have on turtles.

Irene Kelly, sea turtle recovery coordinator for NOAA, says it's the no. 1 concern for the threatened species. That's partly because honu rely on land that is sensitive to sea live rise and partly because temperatures affect the gender of turtles.

Warmer temperatures produce female hatchlings and cooler temperatures produce males. Kelly says that there is currently a "healthy" gender ratio on the Hawaiian Islands, but that isn't the case in other parts of the world.

A study out of Australia reported feminization of sea turtles in the Great Barrier Reef, which is off the coast of northeastern Australia.

The study found that turtles originating from warmer, northern nest beaches were up to 99.8 percent subadult females.

"The warmer the nest, the more females are produced," Kelly said. "That's also why turtles are sensitive to climate change. You need some cooler nests."

Most Hawaiian green sea turtles nest on the French Frigate Shoals in the remote Northwestern Hawaiian Islands, according to NOAA. That area is especially reliant on rising waters being that it is barely above sea level.

"They're more than 50 million years old, they have been adapting to changing oceans and lands for years and years," Kelly said. "It's just, how fast can they adapt to changing conditions now?"

Honu has been doing pretty well overall. NOAA is seeing a 5 percent increase in the population yearly. In 1973 there were only 67 females nesting annually and now there are almost 800.

Other threats to sea turtles include fishery interactions, fibropapillomatosis – which can cause sometimes life-threatening tumors – and injuries from boats.

In regards to recent volcanic activity, NOAA does not suspect the population to be greatly affected.

"It's unknown what the impact has been," Kelly said. "We don't believe there has been a mass mortality, at all."

She said NOAA's priorities are the previous concerns mentioned.

NOAA advises that the best way people can help with conservation efforts is to give turtles space, at least 10 feet, in the water and on land.

To report injured or dead turtles, nesting activities or baby hatchlings, call NOAA's statewide marine animal reporting hotline for sea turtles, monk seals, dolphins, and whales at (888) 256-9840.

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