The way this works for O. mykiss is that they have different trajectories in order to optimize survival, and that some of these trajectories include resident forms. What this means is that individual offspring from steelhead can either residualize (sspend their entire lives in freshwater), migrate to sea in the spring at either one or two years old, and return again that winter or up to 4 winters later. This allows any one fish lots of options - for example, if El Nino kills all the anadromous fish - as it may be doing this year - resident fish survive better even though they produce fewer eggs and their offspring are much smaller. In good ocean years the anadromous fish predominate. In years when the river dries up, as it did in many places this past year, the resident fish take it in the shorts, while the anadromous fish have it made. The drought also killed off many juveniles, so in order for that one year class to be repopulated, anadromous fish return after spending anywhere from 1 to 4 years at sea, seeding the area with offspring. All these trajectories add up to maximum survival - take out any one and the chances of recovering after perverse natural events decreases.
So, if "property rights advocates" think that since there are lots of "trout" in the stream at the moment it's ok to delist anadromous steelhead, they better think again, because that's not what science shows. More likely, in order to recover unhealthy steelhead populations, the trout need to be ESA listed along with the steelhead.
By the way, I hate newspaper articles like this one, where the whole gist of the story is to make controversy by pitting people against each other