The response to the ISRP preliminary comments reviews the problem of poor recruitment of white sturgeon from post-hatch juveniles to yearling age fish. Using a generalized simulation of natural recruitment from spawning by individuals released from artificial production, the sponsors suggest this could be an important solution to making sure white sturgeon are not extirpated before the cause of recruitment failure is solved. Sponsors refer to, and provide, a white sturgeon recovery plan developed for the upper Columbia River (above Chief Joseph Dam) in the United States / Canada trans-boundary region.

In addition to the comments the ISRP provided in the preliminary review, the ISRP stresses here that artificial production actions for white sturgeon, other than those in the historically isolated Kootenai River which is a recognized Distinct Population Segment under the ESA, should consider the species in the Columbia River Basin as a whole, not just isolated reservoir populations. In the upper Columbia River White Sturgeon Plan attached to the proposal, there is a summary of genetic data that suggests that historically gene flow was likely contiguous among the anadromous reaches and that there is currently reduced gene diversity in the upper regions today. The brief culture plan presented in the proposal is a modest increase in the number of families reared currently in Canada from parents captured in the trans-boundary region. The ISRP is not convinced that this adequately addresses all the issues of gene diversity and population viability that arise in this type of endeavor, and consequently do not conclude that it is scientifically defensible. If the sponsors develop future proposals for using artificial culture of white sturgeon, the ISRP urges that even though a proposal may focus on a solution to a problem in a single segment of the mainstem Columbia, it should incorporate a broader perspective on the historic and desired future interrelationships (interbreeding) of sturgeon from across the basin.