Back in April of 2011, DFG rescued a bunch of adult green sturgeon trapped in stilling basins at the Tisdale and Fremont weirs. Green sturgeon is a listed species. Here is a link to the story we did on-topic:
Turns out that in less than a year, anglers reported capturing 2 of the 25 rescued green sturgeon. In crude terms --- not adjusted upward for issues like response rate and tag shedding --- that means 8% of those spawners were handled twice in a year.
That 8% (plus) 'contact rate' (analogous to harvest rate) is a very interesting statistic, because in our decades of tagging sturgeon we've tagged few adult green sturgeon in any given year (most were juveniles and sub-adults) and very few of those tags have been returned to us during the first year after release.
With a tagging study, you (reasonably) assume that what happens to the tagged fish is about the same as what happens to un-tagged fish. Catch-and-release of 8% of the adult green sturgeon in our system means handling those fish protectively is a big deal. Bigger than we've been thinking.
Please leave green sturgeon in the water and let them loose as soon as possible, so you won't be responsible for causing additional harm to them. They can't be legally pursued or possessed.
BDR-IEP Program Manager
California Department of Fish and Game
Bay Delta Region
4001 North Wilson Way
Stockton, California 95205
Phone (209) 948-3702
Phone (831) 372-2581
FAX (209) 946-6355