For thousands of years, native tribes have fished for at least seven species of native fish from the River. Two were eel-like species called "lampreys" -- the Pacific lamprey and the Pacific brook lamprey. Four were minnow-like species, including the Santa Ana sucker, the unarmored threespine stickleback, the arroyo chub, and the speckled dace. The river also supported a run of southern steelhead, large, ocean-going trout that would enter the river during mid-winter rains in order to spawn.
With the channelization of the river that begun in the 1930’s, all of these native species eventually have disappeared in the channel. Today, due to their global rarity, all but the chub are protected under state and/or federal law. All but the brook lamprey survive elsewhere in Southern California, including in the upper tributaries of the LA River, such as Big Tujunga Wash and Arroyo Seco.
The mouth of the LA River in Long Beach, which is now the Port of Long Beach, was originally a vast tidal wetland. It would have supported a rich community of fish, including abundant striped mullet, several species of flatfish, like California halibut and turbots, as well as gobies, and pipefish. Today, this fish diversity probably exists in a reduced form upstream to Willow St. in north Long Beach, where the channel turns cement-lined.
Remarkably, occasional sightings are still made of steelhead trout along such urban coastal waterways as Ballona Creek, suggesting they're still trying to swim upstream into the Southern California rivers. Lewis MacAdams, the co-founder of Friends of the River (FoLAR), is hopeful that the restoration of the LA River, which his organization has spearheaded, can one day restore the natural habitat that will once again attract the steelhead.
“They are the aristocrats of the river fish; they’re very picky and need fresh water and good shade to survive,” MacAdams said. “When the steelheads return to the Los Angeles River, the work of FoLAR will be done.”