A discussion paper on possible new stock groupings (conservation units) for Fraser River chinook salmon : Document de travail sur les nouveaux agrégats possibles de stocks (unités de conservation) pour le saumon quinnat du Fraser

The geographical stock strata are: upper Fraser (those populations upstream of Prince George and including Nechako), middle Fraser (downstream of Prince George but excluding the Thompson), the Thompson River and its tributaries, and the lower Fraser (numerically dominated by fall-returning Harrison-origin fish) (Fig. [...] The early or spring run is comprised of populations for which the peak of migration through the lower Fraser River occurs before July 15; the summer run migrates through the lower Fraser between July 15 and Sept. [...] Glacial History and Colonization A brief overview of glacial history and the subsequent colonization of the Fraser River watershed by chinook salmon is provided to aid in understanding distribution of chinook salmon populations within the watershed. [...] As the ice retreated, a significant portion of the Fraser River drained through the Okanagan watershed and entered the ocean via the Columbia River. [...] Except for the Birkenhead (coastal stream-type) and the South Thompson populations (interior ocean-type), the geographic extent of the inland and coastal groups were thought to correspond with geographic distributions of stream- and ocean-type life histories reflecting post-glacial colonization of by two distinct ancestral lineages.