Among the most popular questions about the Los Angeles River are: "Is it okay to swim in the river?" and "Are the fish safe to eat?"
It shouldn't be surprising that recreation surrounds some of the most prevalent queries about the river. After all, a river used by the people is a river loved. Despite all this curiosity, there have only been a few studies of the wildlife in the Los Angeles River itself.
Among them is the Friends of the Los Angeles River's (FoLAR) 2008 fish study conducted in the Elysian Valley of the Los Angeles River. "It was so important to do a fish study in 2008 because before that, no one really knew what was in the Los Angeles River," says FoLAR special projects manager William Preston Bowling. "We then discovered that there were eight different species in the water. We also found some interesting historical footnotes, like the city of Los Angeles stocked tilapia in the '70s in the river to kill mosquitoes." Most importantly, FoLAR found that the fish were actually healthier and lower in mercury and toxic Polychlorinated Biphenyls (PCBs) compared to those found in the ocean. In its report, FoLAR writes that "The Glendale Narrows is one of the cleanest sections of the river" because the natural river bottom cleans itself and because of the high-quality cleaned water that comes out the treatment plants upstream.
But FoLAR's 2008 fish study was only part of the puzzle. Their hopeful results begged further questions: How do these results compare to the rest of the river? Are there different types of fish on other sections of the river? Are these fish similarly safe to eat?
After five years, FoLAR is finishing what it started by expanding it to two other locations: Long Beach and the Sepulveda Basin. "We'd like to establish a baseline of what's there," says Bowling. "No one's ever done that.'
To aid their efforts, FoLAR called on Los Angeles's fishing enthusiasts, who were attracted by the novelty of fishing the Los Angeles River at Long Beach, as opposed to "spending $200 or $300 fishing in the High Sierras." It was a happy marriage of science and sport, accomplished with the help of the Aquarium of the Pacific in Long Beach (who's also running another citizen science project on sea turtles).
Over four or five sessions, FoLAR stationed about thirty volunteers in fifty-feet increments along the Long Beach section of the Los Angeles River. Some fishermen waded in with feet right in the water to catch their prey. These are the river's newest citizen scientists.
Their mission: to catch fish, store in a bucket of water, and present their catch to three biologists, two from Resource Conservation District of the Santa Monica Mountains (RCD) (Rosi Dagit and Lizzy Montgomery), and one from University of California Cooperative Extension -- Los Angeles (Sabrina Drill). Some of the fish are then measured, weighed, and photographed. Biologists keep some specimens for further study. Others are thrown back to re-populate the river.
Once cataloging is finished, Dr. Richard Gossett from California State Long Beach, who was also part of the 2008 study, will be scrutinizing the fish's stomach content, as well as its levels of mercury, PCBs, pesticides, and flame retardant chemicals.
Results won't be available for another two years, estimates Bowling, but the questions it raises are exciting. "We want to see if there any other species living at the mouth of the Long Beach part of the river. We wanted to see if there is evidence of steelhead trout still remaining. The last steelhead hasn't been seen since the 1940s." Initial results will be reported sometime in August or September, says Bowling. Completing the trifecta, FoLAR is planning a similar effort on the Sepulveda Basin near the mouth of the river in a few months.
That's not all citizen scientist fishermen can do. Drill has established an iNaturalist page, managed by Montgomery, dedicated to recording the fish of the Los Angeles River. Fishermen can upload a photo of their L.A. River catch and where exactly it was caught. Much like iNaturalist does for birds, lizards, and insects, the L.A. River fish page creates a digital community where fishermen can boast of their accomplishments, but also build a record of the river's biodiversity, by simply whipping out their Android or iPhone cellphones.
FoLAR is even appealing to the recreational fishers, says Bowling, by hosting the second annual fishing throwback event called "Off Tha' Hook," one of only two days when Californians can fish the river without a need for a fishing license, this September 5 at North Atwater Park. At nine to ten in the morning, FoLAR is challenging fishermen and anglers to get their hooks into the rarest fish they can find on the river. These fish will again be thrown back into the waters, but not without study by biologists. By ten in the morning, families and children can learn the rudiments of fishing, while enjoying a bit of the river's serene atmosphere.
All the fun and games aside, cataloging the fish in the river is serious business, says Bowling. "It'll help to know what species is present in the river, so we know what special considerations to take when restoring the river."
Find out more about FoLAR's Fish Study program by contacting William Preston Bowling at WPB@FoLAR.org.