For centuries, spring-run Chinook salmon, among California’s most iconic fish, would rest for weeks in these historically cold waters after their brutal upstream journey. Then they would lay eggs and, finally, perish to complete one of nature’s most improbable life cycles. No longer. What once was a place where life began is now one of untimely death. The creek is simply too warm, an astounding 10 degrees warmer than average in some parts of these spawning grounds.