Regarding John Williams’ letter, “Delta smelt in a can,” (Dec. 30), the delta smelt has not colonized southern California reservoirs, a fact apparently not realized by all who read the 2013 April Fool’s Day post on California Water Blog.
In any event, a blog does not constitute a scientific study. The grain of truth in the April Fool’s Day blog is that a number of northern California fishes such as tule perch, hitch, prickly sculpin and Sacramento blackfish have made the arduous journey from the delta to southern California reservoirs and established populations there. If there are smelt in any southern California reservoirs, they would most likely be wakasagi, a Japanese species introduced in the 1950s as a reservoir forage fish and now widely established in the state.
Professor of fish biology
University of California, Davis