03.27.07
Isolation
Sometimes creatures migrate onto the land, and sometimes the land creates its own. When the land creates its own, it does not do so arbitrarily. Every creature is an expression of its creator. Even the immigrants express the character of the land, it is sure, for the mere fact that they have found their place in the community is a reflection of the community, but no creatures express the character of the land quite like the natives.
Some lands, it turns out, are more creative than others. The secret to their creativity, so Charles Darwin discovered, is isolation.
The Pacific Coast is home to a familiar species of trout that is split into two subspecies; one, the steelhead, that lives at sea and spawns in the Pacific tributaries, and another, the rainbow, that lives an entirely landlocked, freshwater existence.
Pacific streams present varying degrees of isolation from the ocean. The Kern River is an extraordinary case, as its waters naturally reach the ocean only in Spring, when flows are high enough to escape the lakes of the Tulare Basin. When the Kern was a free river, it would flow into Kern Lake upon spilling into the Tulare Basin. If the river was high enough, Kern Lake would spill over into Buena Vista Lake. When Buena Vista Lake filled, it would overflow into Goose Lake, and the overflow would continue from there to Tulare Lake. When Tulare Lake overflowed, its excess waters would flood toward the San Joaquin.
At high flows, fish had an opportunity to migrate up and down the basin waterways, but the waterways would dry quickly, and the lakes would recede and even dry as summer and autumn progressed. The basin streams that flowed directly from the Sierra Nevada, the Kings, Kaweah, Tule, etc., were not as isolated as the Kern, because their path to the sea was only impeded by the ample waters of Tulare Lake and their own intermittent character. A fish that ascended up the Kern from Tulare Lake, on the other hand, would have a much longer journey through a chain three smaller, intermittent sinks.
Once fish got above Kern Lake, the river might be perennial, but the Sierra would present its own obstacles. The falls and cascades dropping off the Kern Plateau were the final barrier. Beyond that barrier live the California golden trout.
The domains of the three varieties of golden trout consist of four streams, from west to east: the Little Kern, the Big Kern, Golden Trout Creek, and the South Fork Kern. The Little Kern subspecies is the most endangered, and perhaps the most visually striking. The Big Kern subspecies is relatively indistinct from other rainbow trout, and is thus a rainbow trout by name. The remaining subspecies, the California Golden Trout, inhabits the two adjacent streams, Golden Trout Creek and the South Fork Kern, is perhaps the purest example of golden trout.
