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The View from 60,000 Feet

The View from 60,000 Feet

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The View from 60,000 Feet

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  1. The View from 60,000 Feet Evolution and Diversity of Steelhead Ken Currens Pacific Coast Steelhead Management Meeting 2010

  2. Things weren’t always as they are now The present is often more interesting if we know something about the past West Africa, 1930

  3. Eocene North America 55-30 Million Years Ago Began with rapid warming Polar climates similar to Pacific Northwest today Tropical forests in Pacific Northwest Large lakes and inland seas; none of existing mountain ranges

  4. British Columbia 40-50 Ma Salmonidae already present • Included • Thymallinae • Coregoninae • Salmoninae Start of long-term cooling trend Eosalmo driftwoodensis

  5. Continued cooling allowed dispersal southward Late Miocene (10-5 Ma) The Sabertooth Salmon Oncorhynchyus (Smilodonichthys) rastrosus

  6. Continued cooling allowed dispersal southward Plio-Pleistocene (5-0.1 Ma)

  7. Fossil O. australis In Lake Chapala, Mexico

  8. Distribution of western trouts in North America about 1900 (from Behnke 1992)

  9. Diversity of extant western trouts Westslope cutthroat Yellowstone cutthroat Greenback cutthroat Bonneville cutthroat Coastal cutthroat Colorado River cutthroat Rainbow trout O. mykiss Mexican golden trout & undescribed trout Rio Grande cutthroat Whitehorse & Alvord cutthroats Gila trout Paiute cutthroat California,& Kern golden trouts Lahontan cutthroat Humboldt cutthroat Apache trout

  10. Extant distribution does not simply reflect colonization to the south Extant distribution does not simply reflect southward colonization Formation of mountain ranges Shaping old rivers & creating new ones Columbia basalts & Snake River flows Faulting in Basin & Range Volcanic lava floods Glaciation

  11. Extant distribution does not simply reflect colonization to the south Extant distribution does not simply reflect southward colonization No O. mykissin the Columbia River as recently as 70,000-50,000 years ago Formation of mountain ranges Shaping old rivers & creating new ones Columbia basalts & Snake River flows Faulting in Basin & Range Volcanic lava floods Glaciation

  12. Species & Subpeciesof North American trout Extant distribution does not simply reflect colonization to the south Pleistocene 2.6 Extant distribution does not simply reflect southward colonization Pliocene 5.3 Oncorhynchus Salmo Miocene 23 Oligocene Hucho Brachymystax Salvelinus 34 Oncorhynchus Salmo Eocene

  13. Two Morphologically Different Forms of Steelhead Trout Inland or fine-scale form with redband trout-like characteristics Coastal form Landlocked “redband” trout with cutthroat-like characteristics (Oncorhynchus sp.)

  14. Extant distribution does not simply reflect colonization to the south Coastal & Inland forms thought to reflect dispersal after isolation & differentiation in glacial refuges

  15. Derived Traits Most primitive forms of O. mykissoccur near Gulf of California Coastal rainbow trout & steelhead Mexican golden trout & undescribed trout Goose Lake, Warner,& Chewaucanredbands Columbia River redbands White River redband Catlow Valley redband McCloud redband Fort Rock redband Upper Klamath redband California & Kern golden trouts Primitive Traits

  16. Earliest O. mykissevolved around the Gulf of California & dispersed north Reached Columbia River 32-50K years ago ? Columbia Oregon Desert Basins Klamath Sacramento San Joaquin Gulf of California

  17. Tahoe Glaciation 32K years ago Glacial Lake Missoula Upper Fraser Puget Sound 10-15 K years ago ? Columbia Oregon Desert Basins Klamath Sacramento San Joaquin Gulf of California

  18. 5 B Columbia River L G B B B F G E F B E B B F G J B E E B F L G B B J F B F G J D B B A F E A D D B O B B A D A A B B A L B A A A J A A A B A A A A O B A H 0 A A A J A A A A B A B C B F E C C G C O O C C C C C C Intermediates? Harney (H), Catlow (I) Fort Rock (K) C C B C L I O B B H H G H H I Sacramento: Goose Lake (L), Warner Lakes (O) Chewaucan (J) N K Q N M N N N -5 Q Canonical Variate II K G M N N N N N N N M Klamath: Upper Klamath headwater (M), Upper Klamath Lake (N) Coastal Klamath mountains (Q) M M M M M M M M M -10 M M -15 5 -30 -25 -20 -15 -10 -5 0 Canonical Variate I

  19. Steelhead life-history contributed to greater O. mykissdiversity than often recognized Glacial Lake Missoula Upper Fraser Puget Sound ? Columbia Oregon Desert Basins Klamath Sacramento San Joaquin

  20. Large river systems were more important that glaciation in diversity of O. mykiss Glacial Lake Missoula Upper Fraser Puget Sound ? Glacial refuges & dispersal 37% Columbia 67% Persistence in large river systems Ability to Explain Differences Oregon Desert Basins Klamath Sacramento San Joaquin

  21. Basins now isolated from large river systems played key roles in the evolution of steelhead Glacial Lake Missoula Upper Fraser Puget Sound ? Columbia Oregon Desert Basins Klamath Sacramento San Joaquin

  22. Things weren’t always as they are now The present is often more interesting if we know something about the past Fishing for Ancestral Steelhead in the Oregon Desert Basins, 1985