What are good behaviors at the Imprint Pond?
- Salmon fry are easily stressed, but with a little care, they will behave as naturally as possible
- Move slowly and avoid casting shadows if possible – you don’t want to look like a predator to the fish!
- Whisper or talk in low tones
- Put nothing in the tank, including fingers (water may be contaminated with bacteria)
- Don’t kick the tank or run or stomp feet
What kind of fish are in the Imprint Pond?
- Chum salmon; the word chum comes from the Chinook language word tzum meaning “spotted” or “marked”
- Oncorhynchus keta is the scientific genus and species name
- Dog salmon is another common name referring to the canine-like teeth that develop during the spawning tim
Why are the fish swimming all together? Schooling?
- Fish evolved to swim in schools primarily to better protect themselves from predators (Wikipedia search)
- A group may appear to be a larger fish; tightly schooling of sheer numbers may confuse predators
How many fish are in the Imprint Pond?
- About 38,000 salmon fry as of late April 2018, including school fish from the Salmon in the Schools program
- 30,000 salmon eggshatched and self-released by the 3rd week in March
- 35,000 salmon fry were imprinted and fed and released on February 2, 2018
- 35,000 salmon fryplus about 3,000 school-raised fish will be released on Saturday, May 12, 2018
How are the fish released?
- The stand pipe bucket is unscrewed and the fish flow out of the drain pipe with the water into Venema Creek
- Fish are released as the sun goes down (dusk) so that visual predators like birds leave the area for their nests
How long will the fish fry stay in Venema/Pipers Creek before entering Puget Sound?
- Chum salmon fry seek the estuary soon after they are release from the Imprint Pond, 2-7 days
- Naturally emerging Chum salmon fry from creek bed nest also seek the estuary in 2-7 days
- Chum and Pink salmon share this trait whereas Chinook, Coho, and Sockeye spend up to 2 years in freshwater
What do the fish in the Imprint Pond eat?
- Ground, dried fish meal with added minerals and vitamins; provided by Grovers Creek Salmon Hatchery
How do we feed the fish?
- Note the daily shift feeding amount in the Logbook (visitors and field trips might alter this amount)
- Start at the front-right corner with either the honey bear feeder (small kids) or measured spoons
- Bend down low and sprinkle food very low (close to the water surface) and slow
- Sprinkle slowly until the entire front feeding zone is covered (lots of surface area for lots of fish)
- Wait for current to take the food around and to gauge how much they are eating
- If the food is gone with a cycle of the current, feed more as noted above
- If the food comes around at the surface after a cycle of the current, feed the same or less as noted above
- Feed the daily shift amount or more if the fish seem eager and there is time, less if they are not eating well
How much do these salmon fry eat?
- Fish are fed a daily shift amount (3 times per day, 7 days per week)
- After becoming free-swimming fry (90-120 days from fertilization), we feed 1/8 cups 3 times per day
- Every week or so the amount is increased as the fish grow; we are now feeding 2 ½ cups 3 times per day
- These fish began feeding on March 10 (arrived on Mar 7) and have been feeding for about 50 days (April 28)
Who feeds the fish?
- Fish feeders are Salmon Imprint Stewards and volunteer for Carkeek Watershed Community Action Project
- Every Spring, there 21 Salmon Imprint Stewards feeding fish 3 times per day, 7 days per week
What is imprinting?
- Salmon imprint while developing from fertilized egg, to alevin, to fry, to smolt
- Salmon memorize the smell of their home (natal) waters while imprinting
- Once imprinted, salmon can find their way back to their home waters in 3-5 years to spawn
- Salmon use special cells in their nostrils to record the mineral/chemical signature of their home waters
- Imprinting allows fish that were raised elsewhere to be re-imprinted to new home waters
- While salmon are developing, they can be taught to forget their school aquarium or distant hatchery waters
How do adult salmon find their way back to their home waters?
- The salmon fry in the Imprint Pond were hatched across the Puget Sound in water from Grovers Creek. If they had been released from there, they would return to Grovers Creek as adults.
- Instead, they are kept in the Imprint Pond on Venema Creek long enough for them to ‘forget’ Grovers Creek and ‘remember’ Venema Creek instead.
- The term for ‘remember’ in this case refers to imprinting.
- Salmon uniquely ‘memorize’ (are imprinted with) the chemical and mineral signature of the water that, in the case of our Chum salmon fry, runs down from the neighborhoods of Broadview and Greenwood — the Piper’s Creek Watershed.
- Studies suggest that the geo-magnetic alignment in Earth’s substrate is also imprinted as the fish make their way out of the Puget Sound, the Strait of San Juan de Fuca and into their migratory patterns in the Pacific Ocean.
- After 3-5 years, ocean-run Chum salmon find their way along migratory patterns influenced by current and the imprint/memory of geo-magnetic directions towards their home region.
- The imprint/memory of the waters of Pipers Creek Watershed is thought to be detectable from as far away as 50-100 or more miles from Pipers Creek by the adult salmon that were released as fry from Venema Creek.
- A strong enough memory and suitable conditions (e.g., temperature, tide, stormwater flushed from the Pipers Creek Watershed into Puget Sound) will attract adults into their home waters (native/natal stream) to spawn.
- Conditions may occasionally drive fish into similar, but non-originating streams.
Which direction is the current flowing in the Imprint Pond?
- Water flowing into the Imprint causes the current to flow clockwise (look at the inflow pipe in the pond)
Where does the water come from and go to?
- Venema Creek water comes from an in-creek intake pipe upstream at a higher elevation than the Imprint Pond
- Creek water flows from the intake pipe 200 ft through a service line (pipe) and into Sedimentation Tank #1
- Creek water flows from Sedimentation Tank #1 slightly downhill to Sedimentation Tank #2
- Creek water flows from Sedimentation Tank #2 slightly downhill to the Imprint Pond creating a clockwise current
- Creek water doesn’t overflow the Imprint Pond because a short a stand pipe allows creek water to flow out
- Water flows from the stand pipe (screened white bucket) through a buried pipe downhill into Venema Creek
Which direction are the fish swimming?
- Fish tend to flow against any current in order to maintain control of their position in the water
- Fish that turn and swim with the current will be swept in that direction, which is usually intended
- Fish in the Imprint Pond tend to swim in the counter clockwise direction
How much water is in the Imprint Pond?
- The Imprint Pond is rated at 1,000 gallons and circulates about 900 gallons of creek water.
Where do we get the fish?
- Chum salmon have been given to CWCAP by the Suquamish Tribe’s Grovers Creek Salmon Hatchery since 2004
- The hatchery is about 30 minutes Southwest of Kingston, WA – a 30 minute ferry ride from Edmonds WA
- Grovers Creek Salmon Hatchery: 23175 Indianola Rd NE, Poulsbo, WA 98370 (360) 598-3142
How long have the fish been in the Imprint Pond?
- We keep the fish from 3 weeks to 2 months depending on several variables
- 3 weeks is more than adequate time for the imprinting process and ample feeding
- The larger the salmon fry are when released, the better their survival rate is
- Most of the fish that will be released on May 12, 2018 will have been in this tank for 64 days
When will these fish be released?
- 30,000 salmon eggshatched and self-released by the 3rd week in March
- 35,000 salmon fry were imprinted and fed and released on February 2, 2018
- 35,000 salmon fryplus about 3,000 school-raised fish will be released on Saturday, May 12, 2018
How many fish do we get/release each Spring?
- 80-100,000 Chum salmon fry are received/released from CWCAP program every Spring
When will these fish return to spawn?
- These salmon fry return to these home (natal) waters to spawn after feeding in the Pacific Ocean for 3-5 years
When is the best time to see adult spawning salmon at Carkeek Park?
- Typically, Chum salmon spawners are first seen in Pipers Creek in the 3rd week of October and are gone by the 2nd week of December
- Typically, the number of Chum salmon peak in the third week of November
How many fish return to spawn?
- Carkeek Watershed Community Action Project samples each fish that dies every fall to determine spawning success
- This survey requires that we count and record information about every dead fish
- Though the percentage of adult salmon returns are extremely difficult to relate to releases 3-5 years early, O.5% or less are thought to return to the Pipers Creek system each fall from past releases
What are those other two large blue tanks in the Imprint Compound?
- The two blue tanks near the Imprint Pond are Sedimentation Tanks.
- Sedimentation tanks have no fish, but 3 screens each to block sand and silt from entering the Imprint Pond
- As creek water flows from Sedimentation Tank #1 to Sedimentation Tank #2, sand and silt settles at the bottom of the tanks while clear water flows on to the Imprint Pond
Why do we have bird nets?
- While the Imprint Pond lids are open, bird nets cover the openings to prevent birds from preying on fish fry
- Kingfishers and heron are regular predators that are able to pluck fish from the pond when the lids are open
- The bird nets are lifted when Salmon Imprinted Stewards are staffing the Imprint Pond to allow for feeding, maintenance, visitor feeding, and educational access
What are those smaller black tanks at the back of the Imprint Compound?
- Egg Incubation/Self-release Tank #1 is a 55 gallon tank in-line with the rest of the imprint system plumbing
- Egg Incubation/Self-release Tank #2 is a 5 tank in-line with the rest of the imprint system plumbing
- Each Spring we get 30,000 Chum salmon eggs from the Suquamish Tribe’s Grovers Creek Salmon Hatchery
- The eggs are placed on multiple trays inside the Egg Incubation tanks where they mature over about 3 months
- After becoming free swimming (trays have been removed) the tanks become Self-release tanks
- The free-swimming are not fed, but self-release directly into Venema Creek by way of a buried outflow pipe
- The egg that are added in the first week of January and gone (self-released) by about the 3rd week in March
How long are the Chum salmon at sea?
- 3-5 years
What do adult Chum salmon eat while at sea?
- Herring, other small fish, squid and crustaceans.
How do Chum salmon spawn in Pipers and Venema Creek?
- Adult Chum salmon are fully mature and ready to spawn shortly after they enter the freshwater of the Piper’s Creek system. Chinook and Sockeye salmon do not become sexually mature until they have spent months up to two years in freshwater. Exceptions include Pink and Coho salmon.
- Adult Chum salmon stop feeding perhaps 2-3 weeks before they enter Piper’s Creek in preparation to spawn. This physiological imperative triggers a diversion of energy towards maintenance of reproductive organs.
- Adults are strong swimmers, but poor jumpers (to 10-12 inches) and are restricted to spawning areas below barriers, including minor barriers that are otherwise easily passed by other salmon species.
- Females excavate a nest site (redd — collection of nests from a female) in clear, gravelly, moderate-to-high velocity streams.
- Female lays about 2,000 to 4,000 eggs, depending on size in multiple clutches with multiple males.
- Males (and females to a lesser degree) develop strongly hooked jaws and pronounced canine-like teeth, as well as significant color changes as they compete with other males to fertilize eggs that have been laid in the nests (redds).
- After eggs are fertilized, the female immediately covers the eggs with gravel and may guard the nest or build other nests that may be fertilized by other males.
- All Chum salmon die after spawning, often significantly deteriorated, about 10 days, more or less, after entering fresh water.
- Chum salmon are suited to the short run (lower reach) of the Pipers/Venema Creek system because they are ready to spawn immediately after entering the system. This is unlike long run (upper reach) stream species like Chinook (King) salmon.
- Chum salmon fry released from the Imprint Pond or emerging from the stream bed make their way to the estuary (Puget Sound) in favorable conditions (e.g. temp, current, tide) in 2-10 days
- Other Pacific salmon species such as Chinook, Coho, and Sockeye may remain in freshwater for 6 months up to 2 years before seeking the estuary.
What are those buildings across the road from the Salmon to Sound Trail? A hatchery?
- These building are a King County Metro Pump Station and Combined Sewer Outflow (CSO) Treatment Facility
What are those buildings at the top of the hill just before coming down into the park?
- Nancy Malmgren Environmental Learning Center (ELC), now a pre-school.
- Seattle Parks and Seattle Public Utilities office annex.
- Parks Maintenance Yard
Do naturally nested eggs in Pipers/Venema Creek survive to return as adults to spawn?
- Chum salmon are not tagged, fin-clipped or otherwise marked to indicate that they were raised in a hatchery, so it’s not currently possible to tell whether returning adult salmon were released from the Imprint Pond or emerged naturally from the creek bed nests.
- It is currently thought that the majority of the Chum salmon that return to the Pipers Creek system are hatchery-raised fish that were imprinted and released from the Les Malmgren Imprint Pond.
- Successfully laid eggs in redds (nests) in the fall are subjected to intense and powerful storm water flows during their winter and spring incubation times. Eggs are likely dislodged from these shallow nests and may not survive this challenge.
- It is possible that some spawning adult Chum salmon produce offspring that return to the Pipers Creek system. Until we can tag the fish we release from the Imprint Pond, it’s not possible to know if or how many fish may be returning from stream-spawned fish versus hatchery-inseminated fish.
What’s the difference between wild salmon, hatchery salmon, and farm-raised salmon?
- Wild salmon spawn in their home (natal) waters, their offspring develop in their natural environmental range, and then return to their home waters to spawn the next generation in their home waters. These fish are not adipose fin-clipped.
- Hatchery salmon are captured as they return to their home waters to spawn and are collected for their eggs and milt. The eggs and milt are mixed to produce the maximum number of fertilized eggs. Eggs are raised to some stage of fry development (2-3 months?) and then are released at various sites according to Fish & Wildlife permitting agreements. These fish then spend 95% of their life cycle in their natural environmental range and then return to their home waters to be captured and hatchery-reared into the next generation. Endangered species such as Coho and Chinook salmon may be adipose fin-clipped to differentiate them from wild salmon of the same species. Chum salmon released from hatcheries are almost never adipose fin-clipped.
- Farm raised salmon are commercially hatched from hatchery-fertilized eggs, reared in pens, fed prepared foods in pens, and harvested from pens. Regulations do not permit farmed fish to enter un-penned waters to guard against escape into the wild. In August 2017, more than 250,000 Atlantic salmon, according to state agencies, escaped from a Cooke Aquaculture Pacific net pen off Cypress Island, San Juan Islands. This has lead to cancellations of Cooke contracts and new restrictions on future farm fishing in Washington State waters.
- Imprinting – memorizing how to get back to home waters
- Camouflage – changing body colors to hide from predators
- Eyes – lidless, bird-like, views to each side, unlike forward bicameral mammal vision
- Gills – like lungs that extract oxygen from air, gills extract oxygen from water
- Fins – used to maneuver
- Muscles – used to give power to fins
- Home waters – the place to return to spawn, also known as natal or native waters
- Freshwater – birth and later, spawning waters (creeks, rivers, lakes)
- Saltwater – rapid and significant feeding and growth waters (estuaries, Puget Sound, ocean)
- Estuary – rapid growth area with mix of fresh and saltwater; tidal exchange
- Venema Creek – imprinting tributary of Pipers Creek; major tributary of Pipers Creek
- Pipers Creek – main channel where most fish spawn; Pipers Creek Watershed
- Puget Sound – estuary where salmon species smolt before migrating to the Pacific Ocean
- Pacific Ocean – adult feeding zone following food and temperature currents
- Watershed – all the water that flows to a common low location
- Eggs – newly fertilized with milt (male sperm)
- Eyed eggs – development within the egg showing dark eye structure
- Alevin – hatched egg with emerged fish body and attached egg/yolk sac
- Fry – early free swimming fish without scales
- Smolt – advanced juvenile usually migrated to estuary
- Feeding Adults – ocean going fish, silvery, follows food migration routes
- Spawning Adults – fish returning to home waters undergo extreme physical and physiological changes
- Male – provides milt (sperm) to nested eggs; intensely competes with other males; extreme spawning transformations (colorations, hunched backs, canine-like teeth, hooked jaws (kype)
- Female – build nests (redd) by turning sideways using tail; multiple nests, multiple mates, typically remains at redd site, guarding/tending/waiting for next mate
- Mating – pairing of male and female for the purpose of spawning which results in viable fertilized eggs
- Nest – Redd – females lay about 3000 eggs in multiple nests with multiple mates
- Death – in the Pipers system, fish die within about 10 days of returning to their freshwater home waters; females must find both a suitable gravelly zone and a mate
- Renewal – decomposing fish feed scavenging animals, bacteria, fungi, small plants, trees
- Chum salmon – common name from the word tzum, a Chinook language term that means “spotted” or “marked”
- Dog salmon – common name from the reference to spawners that develop extreme canine-like teeth
- Oncorhynchus keta – scientific name for Chum Salmon
- Anadromous fishes that hatch and spend a juvenile period in freshwater. This is followed by migration to and maturation in the ocean. Adult fish then migrate back up rivers—”anadromous” means “upward-running”—in order to reproduce in freshwater habitats. The length of the initial freshwater period and of the oceanic period vary greatly by species. Similarly, the length of the migration can vary tremendously. Some species travel hundreds of kilometers between their marine habitat and their breeding grounds, while others migrate only a short distance upstream from brackish water to reach freshwater spawning grounds.