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It Takes an Entire Watershed to Raise a Fish. Watersheds and Fish Habitat. Alaska is blessed with an abundance of fish and other aquatic resources. Healthy fish populations depend on healthy watersheds.
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It Takes an Entire Watershed to Raise a Fish Watersheds and Fish Habitat
Alaska is blessed with an abundance of fish and other aquatic resources Healthy fish populations depend on healthy watersheds
Some fish, like rainbow trout, Arctic grayling & burbot, depend on watersheds through their entire life cycle
Pacific Salmon Rainbow trout (steelhead) and Dolly Varden have both anadromous and resident forms Hooligan Sheefish Lamprey others Depend on watersheds for all important life functions Use the ocean only for feeding, growth and development May spend 40 to 70% of their life in freshwater Anadromous Fish in Alaska
We must understand watersheds and freshwater fish habitat needsso we can preserve, protect and maintain these valuable resources
SURVIVAL • Fish must survive as individuals • Individuals must survive to maintain the population • Populations must survive to maintain the species
Fish habitat needs for survival - Feeding • Escape - Overwinter - Spawning - Migration
Juvenile and adult fish have different habitat needs for survival
Where do fish find their habitat needs? • For different • Species • Life stages • Seasons In a Watershed
What is a WATERSHED? • A watershed is an entire region (or “basin”) which drains into a river or river system • Usually includes sub-basins
People find their needs in a community Fish find their habitat needs in a watershed A watershed is like a community for fish
Each fish species prefer different food organisms and the fish go to where their food is found Young fish need different food than older fish People find food in restaurants or grocery stores Young people like different foods than older people Fish and people need food
People are more active during summer Winters may be dangerous for people to survive Fish are more active during summer; they eat more and grow faster Winter survival is difficult for many fish populations Different things happen during different seasons
People go to special places to meet friends or mates Different people have different ways to meet friends Each fish species has unique spawning time, place and strategy Reproduction is important
People move around a city by roads and trails When passage to different parts of a city is disrupted, people cannot find what they need Fish migrate to different parts of a watershed for different needs When passage to different habitats in a watershed is disrupted, fish become stressed Parts of a watershed are connected
People need: Food Security Seasonal activities Socialization/ Recreation Safe passage Fish need: Food Security/Escape Overwinter Spawning Safe Passage A watershed is like a city for fish
Food • Fish need food to grow • Bigger, fast growing fish survive better • Bigger females lay more eggs
Security/Escape • Fish need safe places to rest • Fish need places to hide from predators • Fish need refuge from both floods and drought
Overwinter • Cold water slows fish metabolism • Still waters freeze and are not available for fish • Cold, sluggish fish are more vulnerable to predation and freezing Anchor Ice over Rocks
Spawning • Without spawning and reproduction, a population cannot survive • Where individual populations cannot survive, a species cannot exist
Migration/Passage • Migration corridors allow access to different habitats • Important during all seasons • Different species and different life stages have different needs
Each fish species finds their unique habitat needs for different life stages in different parts of a watershed
A watershed includes components from the mountains to the sea • Glaciers • Tributaries • Lakes • Wetlands • Estuaries
Common Denominator: WATER • Every aspect of fish habitat depends on abundant, clean water • Quantity and quality are both important
Alaska Watersheds • 15,000 cataloged anadromous streams in Alaska (about half the estimated total) • Some watersheds are only a few sq. mi. • The Cook Inlet watershed is 47,000 sq. mi. • The Yukon River watershed is about 300,000 sq. mi. • About 365,000 miles of waterways in Alaska • Over a million lakes in Alaska
A watershed is a factory that makes fish • Different parts of the factory; i.e., habitats, have different functions • Each part (habitat) depends on the other parts • All of the parts work together to produce a product (fish)
The raw material is abundant clean water Energy comes from the sun and nutrients that drive the food chain to produce fish Watershed Fish Factory
Minerals leach from the land Organic matter comes from streambank vegetation (i.e., “riparian areas”) Anadromous fish are an important fuel source for many Alaskan watershed fish factories Nutrients in a watershed
Anadromous fish are important in a watershed • Feed in the ocean & accumulate “marine nutrients” • Some salmon may travel 3,000 miles during their feeding migration • Some chinook salmon may spend five years feeding in the ocean
Anadromous fish are important in a watershed • Carcasses are eaten or decay to release marine nutrients in the watershed • Marine nutrients are in the food chain, riparian vegetation, and groundwater • Some chinook and chum salmon spawn in the Yukon River 2,300 miles inland
Young anadromous fish live in the watershed until they become smolts and migrate to the ocean 1 - 3 (or more) years Adult anadromous fish need the watershed to spawn Resident fish species depend on watershed for their entire life cycle How Important is the Watershed?
Different species live in different places and eat different foods (e.g., young coho live in ponds; young sockeye live in lakes) Most growth is in late summer when water temperatures and food abundance are optimal How Important is the Watershed?
How can you help Protect Fish Habitats in Watersheds? • Learn about fish habitats in watersheds • Participate in a local watershed group • Learn about proposed changes and become involved • Beware of small, incremental but cumulative changes • Work to retain riparian areas
Contact ADF&G for information about anadromous streams: http://www.state.ak.us/adfg/ • Contact ADF&G or other resource agencies about activities that may affect fish and wildlife or riparian areas
It takes an Entire, Healthy Watershed to have Good Fish Habitat
It Takes an Entire Watershed to Raise a Fish Acknowledgements • Funding was provided by Conservation and Reinvestment Act (CARA) • Thanks to Anchorage Waterways Council, ADF&G staff, and others who provided review comments • Thanks to the many people who contributed photographs to make this possible • One last thing: • You can obtain a copy of this PowerPoint file from ADF&G, Division of Habitat and Restoration, Anchorage • 907-267-2285 • Bill Hauser • ADF&G – H&R