An Unexpected Oasis
An industrial factory looms over a developed landscape. Parking lots littered with cars overlook a river surrounded by concrete and an uncrowded bike path. The whir of factory noise is harmoniously accompanied by the hum of a highway in the distance. Oil rigs are drilling nearby. Plastic bags and debris circle in the eddies created by the factories outflows.
A red tailed hawk circles above as a snowy egret surveys the rivers rocky banks. Suddenly, a circular head the size of a grapefruit emerges from the surface. A green sea turtle takes a breath and disappears into the murky waters.
Long Beach, CA, just South of Los Angeles is not a vision of natural beauty, and certainly not where one would expect to find a sea turtle. Yet somehow this concrete landscape is teeming with life. Far from the crystal clear tropical waters where we envision sea turtles, there is not just one but many turtles. They aren't lost, they are thriving. Attracted to the warm water outflows from power plants who use the channeled water as a cooling system, the turtles have found an unlikely refuge in the San Gabriel River.
The turtles flock to the hotspots in the river, and are thought to be there year round. A biologist from the National Marine Fisheries Service, Dan Lawson, found these turtles about 8 years ago. Since then he has involved NMFS Marine Mammal and Sea Turtle division based in La Jolla, CA to attach acoustic tags in hopes of learning more about these urban dwelling reptiles. Lawson has also spearheaded a citizen science project, enlisting animal loving volunteers armed with cameras, to observe the turtles. Each turtle has unique arrangements of face scales that allow them to be identified using imaging software.
Staring out into the area in front of the warm factory water, I spot at least 10 turtles, Lawson estimates there are more than 70 living in the area. There is still a lot to learn about this turtle population. How did they find these hotspots more than a mile inland? What are they eating? Where did they come from?
The turtles are facing many threats. Marine debris such as plastic bags which are strewn about the river, can often be mistaken for food by turtles and other marine life. They can fill their stomachs with undigestible plastic, so they feel full but this can lead to starvation.
Turtles can also get tangled in trash and old fishing lines, which can prevent them from feeding and swimming in some cases. Speeding boats in the river have been known to hit turtles. Lawson says 2016 was a record year for turtle standings, whether or not this has to do with rising populations or more turtles dying, he isn't sure.
The future of the turtles warm water is also uncertain. The factories in this area are planning to stop using the river as a cooling system over the next few years. Under the Clean Water Act, warm water emissions can be considered an environmental pollutant. In this case might be helping the turtles survive this harsh environment. It's unclear how the removal of warm water will affect the turtles and if they'll stick around.
Lawson mentioned to me that he is worried that some people in the area might want to eat the turtles, which I hadn't considered. The area is relatively remote and poaching is a difficult thing to enforce. As he left I headed back to my car to grab my camera. As I returned, I walked up to find two teenage boys, standing over the warm water outflow where the turtles flock, with machetes. In disbelief, I continued walking towards them in hopes of understanding what they were doing. As they saw me approach with my camera, they quickly ascended the concrete steps and disappeared down the bike path. No matter their intentions, there is no doubt that this unlikely oasis is not with out its risks. I breathed a sigh of relief as the turtles continue to swim lazily in the current. No matter what their future may hold in the river, they are safe here for another day.
To get involved with the sea turtle citizen science project, click here.
