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Why So Many Fish in Alaska?. ~ 60-65% of US Food Fish are Landed in Alaska WHY? 1. Alaska is Surrounded by Oceans a. Oceanographic Currents b. Ice Edge Considerations 2. Alaska’s Shoreline & Continental Shelf 3. Geological Nutrient Input into Alaskan Waters
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Why So Many Fish in Alaska? ~ 60-65% of US Food Fish are Landed in Alaska WHY? 1. Alaska is Surrounded by Oceans a. Oceanographic Currents b. Ice Edge Considerations 2. Alaska’s Shoreline & Continental Shelf 3. Geological Nutrient Input into Alaskan Waters a. Loess - Windborne Dusts b. Suspended Sediments in Rivers c. Volcanic Ash 4. Climate Controlled Nutrient Input
Ecology of Boreal & Subarctic Waters I 1. Define Ecosystem Health: Temperate & Tropical Systems - Definition is Species Diversity 2. Evolutionary Divisions in T&T Communities - Speciation by Niche Specialization 3. In T&T Communities: Nearest Neighbor Distance - Meters to Tens of Meters
Specialists Versus Generalists 1. Specialists a. Allows Escape from Direct Competition b. More Efficient - Greater Degree Fine Tuning c. Less Evolutionarily Flexible 2. Generalists a. Less Efficient - Tuned to Different Seasons b. Greater Exposure to Direct Competition c. Greater Evolutionary Flexibility
Ecology Boreal & Subarctic Waters II 1. Ecosystem Health in Boreal & Subarctic Waters - DefinedNot by Species Diversity 2. Evolutionary Divisions B&SA Communities - Generalists Predominate - Seasonal Differences 3. B&SA Communities Nearest Neighbor Distance - Monocultures Covering Vast Areas
Boreal & Subarctic Species 1. Ongoing Biological Research a. Cold Adaptation b. Reproductive Ecology c. Census of Marine Life 2. Needed Research a. B&SA Community Ecology b. Winter Physiology c. Stress, Disease & Monocultures
Boreal & Subarctic Ecology: Bottom Line 1. Use Caution When Attempting to Apply Ecological Principles Derived from T&T 2. Estimations of Over-Fishing Cannot Be Based On Comparisons with T&T Populations 3. Generalist Physiological Parameters Can Be Markedly Different from Niche Specialists 4. Boreal & Subarctic Waters can be Distinct in Their Ecology Compared with T&T 5. Caution: Potential Cryptic Sister Species: Cucumaria lubrica C. vegae assemblage.
1. Area of Continental Shelf 2. Length of Coastline 3. State’s Land Area 4. Number of Unpolluted Rivers 5. Boreal and Subarctic Waters 6. Extremes in Sunlight 7. Ample Nutrients 8. Huge Algal Blooms 9. Excellent Management Why So Many Fish In Alaska?
Human Migrations into North America Clovis Culture ~12,000 bp Probably Multiple Migrations Concept of Bering Land Bridge - Land Migrations Ice Free Corridor Coastal Migrations Some Newer Evidence Most Likely Sites Now Underwater
Linguistic vs DNA Data DNA Evidence Shows Not all Speakers share same DNA Evidence of Multiple Migrations Many after 10,000 ybp Bering Land Bridge Flooded 10,000 ybp Close Affinity with Siberians Newer Groups Moved Further South Tlinket & Haida among most recent