Presentation on theme: "Anadromous Fish of the Bear Creek Watershed"— Presentation transcript:
1Anadromous Fish of the Bear Creek Watershed Teacher Presentation Pages- with accompanying text.
2THANKS TO: Aaron Maxwell for permission to use his presentation 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 Trout’s Healthy Waters Institute.THANKS TO:Aaron Maxwell for permission to use his presentation
3What 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.What are the benefits of being an anadromous fish?Ocean habitat is less variable and contains a large food source. Natural freshwater habitats have less predators and more protection for young fish.
4Bear Creek: Your Backyard, a Salmon’s Home 44 km long204 km upstream from the Pacific OceanTributary to the Rogue RiverMediterranean climate with an average rain fall of 50 cmDry summers, wet wintersNearly 180,000 people living in Jackson Co. = one of the most densely populated watersheds in OR
5What Are the Five Species of Pacific Northwest Salmon? largestChinook (King) lbs, max size 100 lbs!Coho (Silver) Up to 15 lbs.Note that these are pictures of males only. Names in parentheses are other common names.Chum (Dog) lbs.Sockeye (Red) lbs.Pink (Humpback) lbs.smallest
6What Are the Two Species of Salmon found in Bear Creek? Chinook (King) lbs, max size 100 lbs!Coho (Silver) Up to 15 lbs.Note that these are pictures of males only. Names in parentheses are other common names.
7Salmon Are AnadromousAn anadromous fish is one that spends part of its life in fresh and salt water.Fresh Water Salt Water(lakes, streams) (Ocean)Spawning Grow and matureLay eggsImmature life stagesfemale ChinookWhen salmon enter the salt water, their gills, scales, and blood change to survive in the salt water!Salmon are anadromous, spawning and hatching in freshwater, and maturing in salt water. Some types of fish do this in reverse, they are called diadramous. Diadramous fish hatch in the ocean and grow and mature in fresh water.Anadromous fish can survive in both fresh and salt water because their gills, blood, and scales are adapted to deal with changing water conditions. As young salmon prepare to enter the salt water their scales become silver and sleek making them better camouflaged from ocean predators. Their gills reverse the “salt pump”, enabling them to cope with salt water, and their blood adjusts to lower concentration of oxygen found in salt water by increasing the amount of hemoglobin and red blood cells.They also change their behavior, swimming in schools to avoid predators such as seals, whales and other fish in the wide, vast ocean.
8Can You Think of Any Other Anadromous Species Found in Bear Creek? Chinook (King) lbs, max size 100 lbs!Coho (Silver) Up to 15 lbs.Note that these are pictures of males only. Names in parentheses are other common names.
9Can You Think of Any Other Anadromous Species Found in Bear Creek? Chinook (King) lbs, max size 100 lbs!Coho (Silver) Up to 15 lbs.Note that these are pictures of males only. Names in parentheses are other common names.Extra Credit!!What is a non-salmonidanadromous species alsofound in Bear Creek.?(stay tuned for the answer)Steelhead (Rainbow)8 lbs, max size 40 lbs
13Stage 1- EggsThe female salmon lays her eggs in a nest called a redd. Redds are found in gravel beds in freshwater streams.The different species of salmon prefer different types of streams for spawning. For example, Chinook salmon spawn in streams with soft-ball sized pebbles, deep fast-flowing water in sunlit rivers whereas the Coho salmon prefers smaller shaded streams with small gravel layering the bottom of the stream.
14Stage 2 – EmergenceThe young that hatch from eggs are called alevins. They have a sac containing protein, sugar, minerals and vitamins which disappears as they grow older.These alevins live in the streambed between the layers of sediment, under the bottom of the stream.Alevins with Food Sac
15Stage 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.These alevins live in the streambed between the layers of sediment, under the bottom of the stream.trout.htm
16Stage 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.
17Stage 3 – Freshwater Rearing Steelhead fryRotary screw trap used to catch out-migrating fry
18Stage 3 – Freshwater Rearing How long do they stay? Steelhead- May stay in Bear Cr. and tributaries for 1, 2, 3, oreven 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 what’s the difference between rainbow and steelhead?
19The Difference?SteelheadRainbowSteelheadRainbow and steelhead are genetically identical. However, rainboware not anadromous. Rainbow live their entire lives in freshwaterand are therefore much smaller as reproductive adults and do notturn silver.
20Stage 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?As smolts make their way to the ocean, they pass through estuaries, places where salt and fresh water meet.As they travel to the estuary they become silver and sleek to “blend in” with the ocean, loosing their parr marks. By this time their blood and gills are equipped to cope with salt water.Notice the smolt no longer has body stripes. Shiny fish are better camouflaged in the ocean.
21Stage 5 – Ocean Migration and Growth Smolts migrate to the Pacific Ocean where they grow to maturityIn 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.Different species of salmon migrate different distances to reach the ocean. Some, like the Chinook (the largest salmon) migrate up to 1,200 miles to reach the ocean. How long they stay in the ocean also depends on the type of salmon. Some spend only months in the ocean, some, like the Chinook spend several years, allowing them to grow to such large sizes. The Chinook no longer commonly reaches weights of over 100 pounds due to selective fishing and dams on freshwater streams.
22Stage 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 = olfactionOnce the salmon enter the fresh water from the sea, they stop eating and transform into colorful (often bright red) fish with humped bodies and hooked jaws.They can “smell” their way back to the stream in which they were born because they imprint the unique chemistry of the water in their home stream.
23Stage 7 – SpawningSpawning 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.After traveling thousands of miles, surviving predators, and finding her way by smell, the female finds a redd site and lays her eggs. At the same time, a male is nearby to fertilize her eggs.Spawning is the final step for most species of salmon. Shortly after spawning, the fish die. Their carcasses wash up on the shore and are a critical source of nutrients (from the ocean) for the stream.The cycle continues.
24When 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.After traveling thousands of miles, surviving predators, and finding her way by smell, the female finds a redd site and lays her eggs. At the same time, a male is nearby to fertilize her eggs.Spawning is the final step for most species of salmon. Shortly after spawning, the fish die. Their carcasses wash up on the shore and are a critical source of nutrients (from the ocean) for the stream.The cycle continues.
25When 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!After traveling thousands of miles, surviving predators, and finding her way by smell, the female finds a redd site and lays her eggs. At the same time, a male is nearby to fertilize her eggs.Spawning is the final step for most species of salmon. Shortly after spawning, the fish die. Their carcasses wash up on the shore and are a critical source of nutrients (from the ocean) for the stream.The cycle continues.
26When 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 don’t utilize the tribs as much as Steelhead. They require pea-size gravel for spawning.After traveling thousands of miles, surviving predators, and finding her way by smell, the female finds a redd site and lays her eggs. At the same time, a male is nearby to fertilize her eggs.Spawning is the final step for most species of salmon. Shortly after spawning, the fish die. Their carcasses wash up on the shore and are a critical source of nutrients (from the ocean) for the stream.The cycle continues.
27Stage 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 CreekDecomposing salmon
28Extra Credit: What is another non-salmonid, anadromous species found in Bear Creek? Answer: Pacific Lamprey
29A 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.
30Other Cool Native FishCutthroat 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 fishfound in many areas in Bear Cr. Thisrelatively small fish builds egg nests underrocks, which the male readily defends. Prefersriffle habitatKlamath Smallscale Sucker- bottom feeding fishthat likes slow moving water. Moves into BearCr. from the Rogue to breed.Pictured is a Modoc sucker
31Threats 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.Clean spawning gravelGood complex habitatCan you think of examples of good habitat in Bear Creek?Poor habitat
32Threats 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
33Threats 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 bassBrown bullhead catfishBluegillBullfrog tadpole
34Where 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?
35Summary 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 salmon’s home.Coho female
36Disclaimer 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