Net Loss: A History of the Vanishing Steelhead Trout in Southern California | KCET
Net Loss: A History of the Vanishing Steelhead Trout in Southern California
Come winter, the steelhead should be running up Southern California's many flat-bottomed rivers and creeks. They once took their cues from the powerful storms that roll ashore between November and March, dumping heavy rain on upcountry watersheds. When the mud-soaked rush swept downstream, breaching low-water sandbars in coastal estuaries before churning into the ocean, that's been the millennia-old signal for the steelhead trout: it's time to spawn.
In the past, Oncorhyncus mykiss iridium took full advantage of this mix of meteorology, hydrology, and biology to nose into the South Coast's rivers: from the Santa Ynez River and Mission Creek to the Ventura and Santa Clara; from the Los Angeles, San Gabriel, and Santa Ana to the Santa Margarita, San Mateo, and San Luis Rey. Large-bodied--steelhead can pack upwards of 55 pounds on a 45-inch frame; and beautiful--their dark-olive back is delineated from its iridescent silver underbelly by a luminous pink stripe, these powerful swimmers needed every ounce of storm-fed streamflow to help them navigate up to the perennial, cool freshwater pools in coastal-range canyons.
Their difficult passage was a kind of homecoming, for after several years at sea they were returning to the sites of their birth. Like salmon, steelhead trout are anadromous: born in freshwater, within twelve months or so they experience a physiological transformation known as smoltification that allows them to survive in the ocean's harsher chemistry. Propelling their migration toward saltwater are the same winter floods that later will guide them back to their high-country spawning grounds.
This cycle endured for thousands of years, a piscine movement between habitats riparian and marine that has been the mark of each ecosystem's enduring health. Healthy they were, too, if one can judge by the teeming numbers of steelhead that used to ply Southern California waterways. The Santa Ynez in Santa Barbara County, for example, is thought to have supported the largest run of steelhead south of San Francisco: in the winter of 1891, observers stationed at its mouth tallied "great schools of young salmon" heading upriver.
It has been along time since anyone has witnessed its like. Since the early twentieth century, more and more people have crowded into SoCal valleys, nestled into its foothills, and pushed up into its highlands. To insure that these varied terrain serve our needs, we have manipulated the environment to such an extent that we have essentially wiped out the indigenous steelhead population.
Our weapon of choice has been concrete. Those pounding rains, whose annual runoff flipped on the steelhead's reproductive switch, were a different kind of harbinger for the human settlements sited along these same watercourses. To protect against damaging floods, federal, state and local agencies funded the construction of dams big and small, and an interlocking network of channels, ditches, and drains to impound and divert stormwater. In 1920, the Santa Ynez's Gibraltar Dam sealed off a portion of that river's historic spawning grounds and the Bradbury Dam (1953) delivered the coup de grace; as fatal was the Mitilija Dam (1948) sited on the Ventura. These and other dams impeded and confused the steelhead's migratory impulse.
Surely their confusion was only magnified by extensive groundwater pumping for thirsty farms and urbanites that reduced streamflow; bridge-and-highway infrastructure that ripped apart riparian ecosystems; and bulldozed sprawl that buried seeps, wallows, and springs.
No less befuddling has been the human ambition to rearrange these rivers in our image. We worship the linear and find comfort in a geometric order that SoCal's alluvial streams defy. Following the path of least resistance, their course through the local gravely soils have varied depending on the season. After the Los Angeles River squeezes through the Glendale Narrows, for instance, its path to the sea could shift north or south across a vast floodplain; its mouth has followed suit, ranging from Santa Monica Bay to the San Pedro (and at one point it even flowed into what is now Long Beach harbor). Steelhead trout had no trouble adapting to this hydraulic variability, but real-estate developers, engineers, and urban planners have not been as flexible. Their sense of propriety and property, bound up with their abiding faith in technology's ability to box up the wild, led to the pouring of yards upon yards of concrete to turn the 50-mile river into a culvert, straight and true.
This is not a landscape that steelhead could love. By the mid-20th-century, its southern populations had begun to crash; sixty years later, the U. S. Fish and Wildlife Service estimates that its numbers have declined precipitously, by upwards of 99%. What has worked for us has killed them.
This deadly outcome is symptomatic of a larger conundrum: to restore historic steelhead runs will require reconstructing the historic conditions that nurtured their anadromic lifecycle. That's not going to happen, in large part because few of the dams--and the reservoirs that they have created--will be removed. But this reality has not stopped people from trying to revive the world the steelhead once knew. Buoyed by the passage of state and federal clean-water legislation; encouraged by laws protecting endangered species and wild and scenic rivers; and optimistic that ecological analyses can properly guide restoration projects, grassroots organizations have been pushing, suing, and working with governmental agencies to repair what earlier generations tore asunder.
For the past twenty years, the Environmental Defense Center (EDC) of Santa Barbara has been fighting to bring back steelhead to local waters. Most recently, in collaboration with the Army Corps of Engineers and city planners, it has helped redesign the concrete channel that frames Mission Creek, essentially punching holes in it to slow its flow; and plans call for the creation of step pools and rock weirs to facilitate fish migration. In Ventura County, the Matilija Coalition has been working diligently to remove the eponymous dam blocking the Ventura River, modify bridge structures, and regenerate the riverside canopy of oak, sycamore, and willow. Similar efforts are also underway at the mouth of Malibu's Solstice Canyon Creek. EDC's Brian Trautwein spoke to the hopes of many Southern California activists when he predicted that on Mission Creek "we'll restore passage for migrating steelhead and bring this remarkable and resilient species back from the brink of extinction."
Less sanguine news has surfaced in northern San Diego County. Since 2003, the California Coastal Conservancy and its partners have spent hundreds of thousands of dollars trying to revive the San Mateo Creek steelhead population. Despite killing tens of thousands of invasive fish and frogs, in late January 2011 the conservancy threw in the towel. Its failure is attributable to a number of site-specific problems. Camp Pendleton blocked its efforts to restore the creek's lower stretch, a critical hindrance made all the more difficult by the group's inability to extirpate steelhead predators that have continued to stream into the creek's upper watershed from private ponds. The local irrigation district carped that this particular setback revealed a systemic flaw in the very idea of restoration: "If on a smaller, more manageable watershed like the San Mateo they are unable to make progress," Don Smith, director of water resources for the Vista Irrigation District, told the San Diego Union Times, "what makes them think they are able to make progress on a much larger and more complicated watershed?" The Conservancy's response is clear: it has shifted its funds to other sites because it remains convinced that it can return the steelhead to its native habitats.
So are the Friends of the LA River (FOLAR). Under the inspired leadership of poet Lewis MacAdams, its members have worked tirelessly to help Angelenos reimagine this massive concrete channel as a natural river. To achieve this first required public access to the river's steep and hardened banks, then locked behind chain-link. To cut through the fence and open up the space, FOLAR and its allies envisioned a series of pocket parks tied together by walk-and-bike trails. One of these, set within the Glendale Narrows, and now planted with indigenous flowers, grasses, and trees, is Steelhead Park. Its naming is not by happenstance. "It took more than forty years to screw the river up," MacAdams famously wrote in Whole Earth Review in 1995. "I'm sure it will take more than forty years to bring it back to life again. From the beginning we said that not until...the steelhead trout were swimming up the river to spawn...would Friends of the Los Angeles River's work be done."
Until such time, this tranquil spot must stand as mute testimony to the thrashing, silvery surge that once roiled Southern California's free-flowing rivers.