Received: 27 May 2016 | Accepted: 10 August 2016 DOI: 10.1111/eva.12416 ORIGINAL ARTICLE Ancestry and adaptive evolution of anadromous, resident, and adfluvial rainbow trout (Oncorhynchus mykiss) in the San Francisco bay area: application of adaptive genomic variation to conservation in a highly impacted landscape Maeva Leitwein1,2 | John Carlos Garza2,3 | Devon E Pearse2,3 1Technopôle Brest-Iroise, rue Dumont d’Urville, Institut Universitaire Européen de Abstract la Mer (IUEM), University of Brest, Plouzané, The streams draining of into San Francisco Bay, California, have been impacted by France habitat alteration for over 150 years, and roads, dams, water diversions, and other 2Institute of Marine Sciences, University of California, Santa Cruz, CA, USA impediments now block the paths of many aquatic migratory species. These changes 3Fisheries Ecology Division, Southwest can affect the genetic structure of fish populations, as well as driving adaptive evolu- Fisheries Science Center, National Marine tion to novel environmental conditions. Here, we determine the evolutionary relation- Fisheries Service, Santa Cruz, CA, USA ships of San Francisco Bay Area steelhead/rainbow trout (Oncorhynchus mykiss) Correspondence populations and show that (i) they are more closely related to native coastal steelhead Devon E Pearse, Fisheries Ecology Division, Southwest Fisheries Science Center, than to the California Central Valley lineage, with no evidence of introgression by do- National Marine Fisheries Service, Santa mesticated hatchery rainbow trout, (ii) populations above and below barriers within Cruz, CA, USA. Email:
[email protected] watersheds are each other’s closest relatives, and (iii) adaptive genomic variation as- sociated with migratory life- history traits in O.