Presentation on theme: "Anadromous Fish of the Bear Creek Watershed. The Bear Creek Watershed Virtual Tours were created with funds provided by the Bear Creek Watershed Education."— Presentation transcript:
Anadromous Fish of the Bear Creek Watershed
The Bear Creek Watershed Virtual Tours were created with funds provided by the Bear Creek Watershed Education Partners through a grant from the Oregon Watershed Enhancement Board with additional funding from Oregon Trouts Healthy Waters Institute. THANKS TO: Aaron Maxwell for permission to use his presentation
What are anadromous fish? Fish that spend part of their life cycle in freshwater habitats and ocean habitats. Salmon, steelhead trout, and lamprey are the anadromous fish species in the Bear Creek watershed. These fish spend much of their life in the ocean, but must return to the freshwater streams they were born in to reproduce.
Bear Creek: Your Backyard, a Salmons Home 44 km long 204 km upstream from the Pacific Ocean Tributary to the Rogue River Mediterranean climate with an average rain fall of 50 cm Dry summers, wet winters Nearly 180,000 people living in Jackson Co. = one of the most densely populated watersheds in OR
What Are the Five Species of Pacific Northwest Salmon? Chinook (King) 30 lbs, max size 100 lbs! Coho (Silver) Up to 15 lbs. Chum (Dog) lbs. Pink (Humpback) 2-5 lbs. Sockeye (Red) 7 lbs. largest smallest
What Are the Two Species of Salmon found in Bear Creek? Chinook (King) 30 lbs, max size 100 lbs! Coho (Silver) Up to 15 lbs.
Salmon Are Anadromous An anadromous fish is one that spends part of its life in fresh and salt water. Fresh WaterSalt Water (lakes, streams) (Ocean) Spawning Grow and mature Lay eggs Immature life stages female Chinook When salmon enter the salt water, their gills, scales, and blood change to survive in the salt water!
Can You Think of Any Other Anadromous Species Found in Bear Creek? Chinook (King) 30 lbs, max size 100 lbs! Coho (Silver) Up to 15 lbs.
Can You Think of Any Other Anadromous Species Found in Bear Creek? Chinook (King) 30 lbs, max size 100 lbs! Coho (Silver) Up to 15 lbs. Steelhead (Rainbow) 8 lbs, max size 40 lbs Extra Credit!! What is a non-salmonid anadromous species also found in Bear Creek.? (stay tuned for the answer )
Do You Know the Difference? Source:
A Look Inside the Mouth Source:
Stage 1- Eggs The female salmon lays her eggs in a nest called a redd. Redds are found in gravel beds in freshwater streams.
Stage 2 – Emergence The young that hatch from eggs are called alevins. They have a sac containing protein, sugar, minerals and vitamins which disappears as they grow older. Alevins with Food Sac
Stage 2 – Emergence When do Salmonids In Bear Cr. Emerge? Chinook, Coho, and Steelhead eggs begin hatching in late winter. Alevins stay hidden in the spawning gravel until the are developed enough to move and feed in calmer waters in the early spring. Often observed in pools along Bear Cr. trout.htm
Stage 3 – Freshwater Rearing Once they have consumed the food sac, juveniles called fry, emerge from the stream-bed and feed on aquatic insects. Some salmon species head immediately for the ocean, some stay in fresh water for up to 3 years. During their trip to the ocean they undergo the changes to help them live in salt water, this is called smoltification. Notice the bars called parr marks, which help the parr camouflage in fresh water streams.
Stage 3 – Freshwater Rearing Steelhead fry Rotary screw trap used to catch out-migrating fry
Stage 3 – Freshwater Rearing How long do they stay? Steelhead- May stay in Bear Cr. and tributaries for 1, 2, 3, or even 4 years before leaving. Chinook- Begin leaving Bear Cr. in the early spring and generally swim directly to the estuary. Coho- Also leave Bear Cr. in the spring, but will stay within the Rogue River watershed for up to 2 years before migrating out to sea. Extra Credit!!! So whats the difference between rainbow and steelhead?
The Difference? SteelheadRainbow Steelhead Rainbow and steelhead are genetically identical. However, rainbow are not anadromous. Rainbow live their entire lives in freshwater and are therefore much smaller as reproductive adults and do not turn silver.
Stage 4 – Estuary Rearing Smolts transform into ocean fish in estuaries. Their scales, gills and blood change to survive in salt water. They must avoid Herons, Kingfishers, and other fish in the estuary! Where is the estuary that salmon from Bear Cr. use? Notice the smolt no longer has body stripes. Shiny fish are better camouflaged in the ocean.
Stage 5 – Ocean Migration and Growth Smolts migrate to the Pacific Ocean where they grow to maturity In the ocean, they grow to large sizes, the Chinook once reached over 100 lbs. These sleek fish must survive orca, seal, sea lion, and fisherman predation.
Stage 6 – Spawning Migration After spending time in the ocean, salmon migrate back to the exact stream in which they were born. How do they know where to go? Smell and taste = olfaction
Stage 7 – Spawning Spawning occurs in the same stream in which the salmon hatched. Females select redd sites and deposit eggs. At the same time, a male fertilizes them, expelling his milt onto the eggs.
When and Where do Salmon Spawn in Bear Creek? Winter Steelhead- Adults enter Bear Cr. in December- May. Spawn in the upper portions of the main- stem of Bear Cr. and tributaries such as Neil, Wagner, and Walker Creeks. North Mountain Park is a good place to see spawning steelhead.
When and Where do Salmon Spawn in Bear Creek? Fall Chinook- Fall Chinook enter Bear Cr. in September- November and spawn shortly thereafter. Despite being the largest fish in Bear Cr., they prefer to stay in the larger waters and do not migrate upstream as far as steelhead or coho. You can even see spawning Chinook behind the mall in Medford!
When and Where do Salmon Spawn in Bear Creek? Coho - Coho enter Bear Cr. usually in January and February. They spawn almost immediately after reaching suitable habitat. Very few coho remain, in fact they are listed as Threatened under the ESA. You may have seen coho spawning in Ashland near Lithia Park this year. Generally coho prefer smaller streams for spawning than do Chinook, but dont utilize the tribs as much as Steelhead. They require pea-size gravel for spawning.
Stage 8 – Nutrient Recycling After spawning, the adult salmon die. At this point the decomposing bodies provide nutrients from the sea to the stream system. This is critical to the health of streams and rivers, feeding not only other animals, but also plants and even juvenile salmon themselves! During the winter you can smell salmon carcasses along the banks of Bear Creek Decomposing salmon
Extra Credit: What is another non-salmonid, anadromous species found in Bear Creek? Answer: Pacific Lamprey
A Little about Pacific Lamprey (An important and interesting native fish) Lamprey hatch from redds similar to salmon in Bear Creek. Juveniles called ammocetes are blind, filter feeders that embed themselves in sandy river bottoms for up to 7 years. Ammocetes then develop eyes and gills and migrate out to sea. Upon reaching the ocean they parasitize other fish and marine mammals by attaching themselves with suction- like mouths. Once fully grown and mature they release from their host, swim back to Bear Creek and spawn in the early spring.
Other Cool Native Fish Cutthroat Trout- a salmonid species found high in the headwaters of Bear Cr. Common in upper Neil Cr. Bear Cr. probably had anadromous cutthroat at one time. Reticulate Sculpin- a benthic fish found in many areas in Bear Cr. This relatively small fish builds egg nests under rocks, which the male readily defends. Prefers riffle habitat Klamath Smallscale Sucker- bottom feeding fish that likes slow moving water. Moves into Bear Cr. from the Rogue to breed. Pictured is a Modoc sucker
Threats to Fish Survival Temperature-most salmon cannot tolerate temperatures above 60°F. High temperatures means low dissolved oxygen. Bear Cr. often exceeds this threshold in the summer. Causes include water withdrawals, loss of riparian shade, loss of hyporheic flows, warm water inputs, dams that slow and warm the water … Loss of Habitat- Bear Cr. has been channelized over the years thereby reducing the complex habitat and spawning gravels required by salmon. Different life stages require different habitat. Good complex habitat Clean spawning gravel Poor habitat Can you think of examples of good habitat in Bear Creek?
Threats to Fish Survival Urban and agricultural pollution- many of the chemicals and nutrients we use enter Bear Creek untreated and harm fish. Poor forest practices- Removing trees near Bear Creek and clear-cutting steep slopes near headwater tributaries increase the amount of sediment which smothers developing eggs. Dams and diversions- Dams, irrigation diversions, and even road culverts may prevent fish from making it to suitable spawning habitat. Increased water velocity by culverts may also impede certain species of fish. ?? Are you poisoning salmon? Removal of riparian vegetation
Threats to Fish Survival Introduced Species- many species like bass, sunfish, and catfish may be fun to catch, but actually compete with, eat, and harm native fish and amphibian species. Bullfrogs, voracious non-natives, don t make matters any better. Where do you often find introduced species of fish? Do those places look like good salmon habitat? How does temperature factor? Smallmouth bass Brown bullhead catfish BluegillBullfrog tadpole
Where are the majority of fish barriers located? Which barriers do you think have the largest impact on fish? Can you name any barriers fish might encounter on the Rogue River?
Summary There are many species of fish that remain in Bear Creek. Because of habitat degradation many of these species, including salmon and steelhead, are threatened with local extinction. There is hope. Celebrate native fish by teaching others about their backyard and by thinking about what you can do to improve a salmons home. Coho female
Disclaimer and credits- Photos provided by Jason Bauer, Carson, and the internet. GIS contributors include Dick Best, Chris Zanger and Terri Eubanks. Technical info was derived from Bear Creek assessment provided by the Rogue Valley Council of Governments, and other sources. Thank You All