Fodder fish
Pacific sardine
SARDINOPS SAGAX
Formerly harvested in stupendous numbers (up to 700,000 metric tons per year), sardine populations finally crashed in the mid-1900s from rampant exploitation. At the time, they were ground into byproducts that went into several things including livestock feed, paint, soap and margarine. During the sardine’s absence, anchovy populations apparently soared, becoming the dominant prey item and encouraging Mexican birds such as elegant terns to shift their range northward in pursuit of their favorite food. Within the last decade, however, sardine populations have begun to rebound a bit. They have recently been observed returning as far north as British Columbia. Vast schools that include millions of sardines now live year-round south of Point Conception, where upwelling currents are less intense and the planktonic larvae they eat find refuge. Predators swimming into densely packed schools of sardines will be completely baffled as these fish part around them like seamless walls of shimmering mirrors.
KEY CHARACTERISTICS:
Sleek, spindle-shaped fish about a foot long, with a row of dark spots down its body.
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Threadfin shad
DOROSOMA
PETENENSE
Every morning at sunrise, schools of diminutive threadfin shad leave shoreline hiding places and dash for deeper waters. During the day they make a migratory circuit of the lake or river in which they live, devouring microscopic plants and animals along the way, and in turn being followed by hungry predators waiting for a chance to grab their own snack. But shad are expert at avoiding hungry fish such as bass. They congregate in dense groups where their silvery scaled bodies combine to create a virtual hall of mirrors. Threadfin shad spend their daylight hours gulping mouthfuls of water and pumping it across long, closely set gill rakers that filter out superabundant plankton. When introduced to California in the 1950s, no one knew how prolific they could be. Within 18 months of being introduced to Lake Havasu, 1,000 shad blossomed into several million fish that colonized the lower Colorado River. Today they are widespread in lowland waters throughout California.
KEY CHARACTERISTICS:
A silvery, 3-inch-long fish with a potbellied appearance and a lance-like ray behind the dorsal fin.
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Northern anchovy
ENGRAULIS
MORDAX
Victims of nearly every feeding frenzy on the Pacific Coast, the poor northern anchovy is a fish so abundant that everyone wants to eat it. Not only is this incredibly important fish on the menu for sea lions, pelicans, tuna and countless other predators, but it also supports one of the most prolific fisheries on the West Coast. It’s no wonder that to evade the gnashing teeth, striking bills and swirling fins of their many predators, anchovies huddle in massive schools for protection, creating confusion by turning and flashing their silvery bodies in unison. In such numbers, schooling anchovies have so many eyes looking out that it becomes extremely difficult for a predator to launch attacks without being seen. So significant is the fishery for humans that after anchovy populations crashed in the El Nino of 1972-73, a switch was made to soy proteins, resulting in the clearing of vast swathes of the Amazonian rain forest for agriculture.
KEY CHARACTERISTICS:
A slender fish that grows to 7 inches long, with metallic blue-green upper-parts and silvery body.
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Red
shiner
CYPRINELLA
LUTRENSIS
The red shiner spreads like a weed, surviving in incredibly diverse habitats. It originated in the Mississippi River and reached California when fishermen dumped it into local waters. In 1979, an advisory committee to the Department of Fish and Game asked that the fish, only found in the Colorado River at the time, be banned as bait for fear that it would infiltrate state waterways. But department staff folded under pressure from the bait-fishing industry, and these fish are widely sold as bait. The problem with red shiners is that they tolerate a remarkable range of temperatures as well as highly disturbed and polluted waters such as canals, ditches and reservoirs. They not only out-compete native fish but also apparently feed on their larvae, adding pressure on some of California’s threatened native fishes. Spawning shiners broadcast their eggs widely so the sticky eggs can adhere to a variety of substrates, an unusual reproduction strategy that appears to be successful.
KEY CHARACTERISTICS:
This small fish has silver sides and a compressed body; breeding males’ fins turn red-orange.