Once uncountably numerous, the Delta smelt was placed on state and federal endangered species lists in 1993, stopped appearing in most annual sampling surveys in 2016, and is now, for all practical purposes, extinct in the wild. At least, it was. Then, in December, state and federal biologists released more than 12,000 adult Delta smelt, born about a year earlier in a University of California, Davis laboratory, into the lower Sacramento River in an effort to draw the species away from the brink of oblivion.