A MARTÍNEZ, HOST:
Often, when we tell animal stories, it's about how bad they're doing, which was the case for green sea turtles on the West Coast not too long ago. But a different story is playing out right now just south of Los Angeles, where those turtles are coming back in a major way - right in the middle of suburbia, in the San Gabriel River. Here's LAist's Jacob Margolis.
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JACOB MARGOLIS, BYLINE: Given how the San Gabriel River looks, it's tough to imagine that it's hosting what's likely one of the largest gatherings of sea turtles in Southern California. I mean, there's people speeding by on the 605 freeway. There's a suitcase floating by. And you've got to go down these huge concrete embankments just to get to the water.
Oh, yeah. That's really wet (laughter).
But when you do, sure enough, within no time at all, gliding just beneath the murky surface...
There we go - green sea turtle (laughter). This is amazing.
Green sea turtles like this one are often born on a beach about 1,600 miles away, in Michoacan, Mexico, where masses of these turtles pop out of their shells all at once and start scurrying towards the water.
JEFFREY SEMINOFF: The vast majority of those animals are not the lucky ones.
MARGOLIS: Jeffrey Seminoff is a turtle researcher with the National Oceanic and Atmospheric Administration.
SEMINOFF: They'll get picked off by ghost crabs or raccoons or birds or fish. They just don't make it. You know, less than 1 in 100 hatchlings typically make it to adulthood.
MARGOLIS: There are different populations of green sea turtles around the world, and many of them are either endangered or threatened - often due to habitat loss, ship strikes and accidentally getting caught by fishermen. The green sea turtles here in Southern California were listed under the Endangered Species Act in the 1970s. Their population was cratering - in part because they and their eggs were being harvested on their nesting beaches in Mexico. But by the early '90s, Mexico had taken new steps to protect them. And in the past five years, their population has exploded here.
SEMINOFF: It really does sort of distill down to the fact that if we don't eat them and we protect their nesting beaches, they're going to do quite fine.
MARGOLIS: Helping struggling animals isn't always that straightforward. But unlike other species of turtles, the green turtles near LA tend to live closer to the coast, reducing the risk of accidental bycatch and ship strikes. And with their numbers growing, they're expanding into new spots.
SEMINOFF: Twenty years ago, to talk about turtles up in Orange County was unheard of. Now it's pretty much a common sight, whether it's in Seal Beach National Wildlife Refuge or Bolsa Chica or in San Gabriel River.
MARGOLIS: Tina Fahy, NOAA's West Coast Sea Turtle Recovery Coordinator, took me to a spot in the river where the vegetation ends and the giant concrete walls begin.
TINA FAHY: I think it's only recently that we've really realized that green sea turtles are coming this far up the river.
MARGOLIS: Scientists have been surprised to see this many of them here. It's something that they still need to study to better understand. But they think that this highly developed area might be kind of a strange sort of turtle oasis. There's lots of algae to eat. The concrete walls seem to keep the water warm, and...
FAHY: An area like this that is relatively quiet other than the freeway noise, that doesn't have vessels, that doesn't have people with hooks and line, is actually a really good, protected area.
MARGOLIS: And as their population expands and waters warm due to climate change, the turtles could keep going further north, giving scientists an opportunity to study these resilient animals in totally new habitats.
For NPR News, I'm Jacob Margolis in Los Angeles.
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