Fish Ladder Reopens and the Sockeye are here!

After a thorough annual spring cleaning, the fish ladder at the Ballard Locks reopens tonight, just in time for the arrival of the sockeye salmon and Memorial Day weekend.  The sockeye are on their way.  Our insiders tell us that four sockeye were recently spotted in the area.

Of the 3 Pacific salmon species that use the fish ladder, the sockeye are the first to return each year, coming back from the Gulf of Alaska where they have been feeding for the last two to three years. The majority of the sockeye that pass through the Ballard Locks were hatched on the Cedar River and are returning there to spawn.

When we see the sockeye at the Locks they are silver in color.  It’s called the “ocean phase.”  The sockeye in this phase are easily identified from other salmon species by the lack of spots on their backs.  Adult sockeye will average from 24 to 30 inches in length.  They weigh from six to eight pounds.  As they journey through fresh water to the spawning beds their bodies will take on the distinctive red color called the “freshwater phase.”

After moving through the Ship Canal and lakes Union and Washington, the sockeye salmon will reach their spawning beds in late September or early October.  Each female will lay several thousand eggs in the gravel of the riverbed.  Salmon die after spawning, becoming an important part of the ecosystem as their decaying bodies return essential nutrients like nitrogen and phosphorus to the soil.

The fish ladder viewing gallery is open daily from 7 a.m.-8:45 p.m., there are displays there and in the Visitor Center (10 - 6:00 daily) with additional information on the salmon life cycle.

Salmon Season!

Head on over to the Chittenden Locks to see the sockeye salmon (link to our past article) moving through the fish ladder. The run is now at its peak, about 23,000 fish have passed through as of 7/5/11.

Some early chinook salmon have been spotted so if you see a larger fish with spots on its back in the viewing window, you are seeing a chinook (sockeye have no spots.) The chinook run will peak early August and then will come the coho salmon, the last of the 3 salmon species that use our fish ladder.

Don't forget the weekend concerts on the lawn- every Saturday and Sunday at 2 p.m.!

Spring Cleaning: Fish Ladder Cleaning Finishing Up This Week

The fish ladder has been undergoing its normal yearly maintenance from May 16 - 27 and will be reopening this Friday.

Check out the pics from the slideshow below or last year's Fish Ladder Spring Cleaning blog post!

Steelhead at the Locks (or not.)

Onchorynchus mykiss is a mouthful in more ways than one. It is tricky to say, and it tastes delicious! It’s also a fish that is very rarely seen in the viewing window of the fish ladder. At one time there were two to three thousand steelhead migrating through the Chittenden Locks in winter. Nowadays you are quite lucky to see just one!

What are Steelhead?

Steelhead are a type of Pacific salmon. Like other Pacific salmon, they rear in fresh water until they become smolts, then migrate to the ocean. This stage can last anywhere from about one to four years.

Once in the ocean, they can travel thousands of miles; they keep getting larger as they find larger food sources, usually in colder waters. This stage can also last from one to four years. Upon returning to their native streams, they will deposit eggs. Unlike their cousins the Coho, Chinook, Sockeye, Chum, and Pink salmons, the Steelhead are not always destined to die after they spawn; they may return to the ocean several times in their lives. In that way they are more similar to their distant cousins the Atlantic salmon. Steelhead are quite difficult to track, but some have been tagged and are known to have traveled all the way from the Columbia River basin to the Sea of Japan and back, in their lifetime.

If an Onchorynchus mykiss spends its entire life in fresh water, it is called a Rainbow Trout. They are the same species, but have differing lifestyles. Steelhead normally weigh about 8-11 pounds, but can get as hefty as 40 pounds or more. They are quite silvery in color, with many spots on all parts of their bodies, and a reddish or rainbow hue along their sides.

The run of Steelhead that came through the locks was a winter run and was therefore fully mature when they returned upstream. Summer runs come back younger and stay in the rivers until they mature.

So, What Happened to the Steelhead at the Locks?

The numbers of Steelhead have gone from about 2600 in 1983 to less than 10 in more recent years. It is difficult to get any numbers after 2008, when four fish were counted in the rivers that feed into Lake Washington. At that time only two redds were found; a redd is a nest with eggs in it.

The numbers of these fish in the Lake Washington system are so low that they seem to be on the verge of extinction. With that said, a few are seen every year and there are probably some that pass through without being seen or identified at all.

There are many factors that have contributed to their decline, such as destruction of habitat, pollution, man-made obstacles such as dams, ocean conditions and over-harvesting. It is also possible that some have decided to remain in fresh water and essentially convert to their Rainbow Trout mode. We also know that Steelhead prefer a fast, cold river to breed and rear in. Unfortunately, the water above the Locks is warmer than it was at one time, due to the urbanization of the environment.

Of all the factors have affected the Steelhead, none is as obvious and dramatic as the yearly visitation of the California sea lions. The most famous of these hungry predators was called Herschel. He arrived in 1983 and discovered that steelhead were pretty easy pickings at the Locks. That was when the steelhead run first began to decline.

Herschel, and other large male sea lions voraciously ate over half of the returning steelhead that returned to the locks for several years in a row. Although there were often as many as 40 or more sea lions in the area, it was observed that most of the devastation was usually caused by two or three of the largest ones.

While the steelhead counts have continued to decline, the sea lion counts have been growing. In 1972 the Marine Mammal Protection Act was first enacted. Since that protection was put in place, the number of California sea lions increased from around 50,000 to around 250,000. Each year shows a small percentage of increased population growth.

Numerous methods were employed to deter these Pinnipeds, (fin-footed mammals), but nothing was very effective. Some of the techniques used were underwater firecrackers, known as seal bombs; rubber bullets; acoustic harassment devices; nets; and poisoned fish. The sea lions were also trucked several times to other areas as far away as California, but always swam back. At best, these methods slowed the sea lions down, but not for long. Each time, they got wiser and more sure of themselves.

Meanwhile, the steelhead run has not been able to recover. The original run was a wild run; at one point a hatchery run was introduced with the hope of enhancing the numbers. Unfortunately, they competed with the wild fish instead.

There is no easy answer to this steelhead situation. What will become of the once wild steelhead run in Lake Washington? If a run still exists will it ever grow? Perhaps, we will have to go elsewhere to celebrate this beautiful fish, our state fish.

Article written for FoBL Blog by Stacey Gilbert

Information for this article was sourced from:

“Stock Report-Lake Washington Winter Steelhead.” wdfw.wa.gov 2009. 01 February, 2011. http://fortress.wa.gov/dfw/gispublic/apps/salmonscape/salmonscapeJSP/summaryStockReport.jsp?SasiStkNum=6154

Guterson, David. ”This Seal Doesn’t Have Everyone’s Approval.” http://sportsillustrated.cnn.com 1990. 23 January 2011. http://sportsillustrated.cnn.com/vault/article/magazine/MAG1137071/index.htm

“Steelhead.” www.kingcounty.gov. 2008. 05 January, 2011. http://www.kingcounty.gov/environment/animalsAndPlants/salmon-and-trout/identification/steelhead.aspx

It's Silver Time!

Coho salmon are commonly called silvers because of their shiny appearance. The coho run usually starts in mid-August and will peak around the second week of September, it is the last of the 3 salmon species to use the Lake Washington Ship Canal fish ladder.

Adult coho average 6 to 12 pounds and are identified by the fine spots on their back and upper tail lobe. If you have difficulty telling a coho from a Chinook, look at their mouth--the coho will have pale color flesh along their gum line while the Chinook will have dark color flesh at the base of their teeth (hence, young Chinook are sometimes called ‘blackmouths.’)

Coho return to spawn in their natal stream when they are about 3 years old, like all salmon species, the males develop the very distinctive hooked upper jaw (called a kype) and teeth in order to fight for dominance in the spawning beds. Some of the coho run will be returning to the hatchery in Issaquah, others will spawn in the local creeks where they were hatched.

Coho are found along the Pacific coast from San Francisco to Alaska.

All Hail the Kings!

The Chinook salmon are beginning to arrive at the Locks fish ladder.

Commonly called ‘king’ salmon because they are the largest of the Pacific salmon species, they are about 36” long and average 15 to 20 pounds. Seeing them in the fish ladder viewing gallery they are easily distinguished from the sockeye by the spots on their back and tail (sockeye have no spots.) The Chinook will also be larger and sometime have an olive green sheen on their bodies. The run will peak around the second week of August.

About 80% of the Lake Washington Ship Canal Chinook run is returning to the hatchery in Issaquah, the other 20% of the run will return to whichever river or stream where they were hatched 3-5 years ago. Hatchery fish are identifiable by the absence of their adipose fin (the tiny fin in front of the tail;) this fin is clipped off in the hatchery before the fish is released. Wild Chinook salmon are on the Threatened Species List.

Chinook salmon range along the Pacific coast from Alaska to California and they are prized as both a commercial and as a sport fish.

Sockeye Swimming Up the Ladder

Just like clockwork the salmon are returning to the fish ladder at the Chittenden Locks.

Of the 3 Pacific salmon species that use the fish ladder, the sockeye are the first to return each year, coming back from the Gulf of Alaska where they have been feeding for the last 2-3 years. The majority of them were hatched on the Cedar River and are returning there to spawn.

When we see them at the Locks they are silver color, called 'ocean phase,' and are easily identified from other salmon species by the lack of spots on their backs. Sockeye will average 6-8 pounds and 24-30 inches long. As they journey through fresh water to the spawning beds their bodies will take on the distinctive red color called 'freshwater phase.'

Moving through the Canal and lakes they will reach the spawning beds in late September/early October. Each female will lay several thousand eggs in the gravel of the riverbed where they remain for 3 months until hatching into tiny fish called alevins. Both male and female salmon die after spawning, thereby becoming an important part of the ecosystem as their decaying bodies return essential nutrients- nitrogen, phosphorus- to the soils along the streams.

The fish ladder viewing gallery is open daily from 7 a.m.-8:45 p.m., there are displays there and in the Visitor Center (10 - 6:00 daily) with additional information on the salmon life cycle.

Fish Ladder is Open! Sockeye are Swimming!

A source at the Ballard Locks has informed us that the fish ladder is open and sockeye salmon are swimming upstream.

Pictures and more words coming soon...

Spring Cleaning: Preparing the Fish Ladder for Salmon!

We're spring cleaning & getting ready for guests--the salmon are coming!

The fish ladder at the Chittenden Locks will be closed May 24-June 4 for annual cleaning, inspection and maintenance; the fish viewing gallery will be closed to the public during this time.

There actually was a fish ladder constructed in 1917 with the spillway dam; it was very primitive as we didn't know much about salmon migration in those days. The ladder was not very effective and many salmon moved upstream through the locks and were injured by boats and propellers or by hitting the barnacle-encrusted walls and gates.

In 1976 the Corps of Engineers completely rebuilt the ladder, increasing the number of weirs (steps, or waterfalls) from 10 to 21, and increasing the flow of water. The rush of water out of the base of the ladder attracts the salmon away from the locks, as salmon instinctively know to go against the flow to trace their way back to their natal stream. The smell and taste of their home stream in genetically imprinted while they are young and they follow that unique smell/taste back upstream to spawn.

Moving quickly up the waterfalls the salmon jump each step or swim through tunnel-like openings between each weir. Weir 18 of the ladder was elongated to make the fish viewing gallery possible; here the salmon often spend a few hours resting and acclimating to fresh water before continuing their journey upstream.

The sockeye salmon is the first salmon species to return to the Lake Washington Ship Canal each year, the early ones usually show up around mid-June and the run normally peaks in early July. The word sockeye is a corruption of "sukkai", the name for the fish used by the Native Peoples of southern British Columbia.

Chinook (king) and Coho (silver) salmon runs follow during the summer months.

Check back often for more information and updates on the salmon runs at the Chittenden Locks!

All photos courtesy of USACE/Historical Collection Lake Washington Ship Canal

Smoltificatious!

Ever wonder what those big white metal tubes were on the spillway dam at the Locks? Read on.

The Corps of Engineers has installed those tubes; they are smolt flumes designed to help juvenile salmon safely bypass the Locks on their migration out to the ocean.

Studies had shown that smolts (juvenile salmon) were having a difficult time going through the Locks, which is their only passageway from the Lake Washington basin out to Puget Sound. Fish would get injured or killed when pulled into the filling tunnels or going over the spillway dam. In 1995 a prototype flume was installed to determine their feasibility, when deemed successful the current models were built at the Puget Sound Naval Shipyard and installed in May 2000.

The 4 flumes are different sizes to better regulate the outflow of water from the freshwater lakes. The narrow outer ends of the tubes contain an electronic screen to read the PIT tags that are implanted in some of the smolts. PIT is "passive integrated transponder," a microchip type of tracking device.

Standing on the spillway dam late April to early July you may see dozens of small (4"-6") fish shooting out of the flumes with the water, these are the sockeye, chinook and coho smolts headed out to the ocean. What looks to us like a dizzying fall is "just another waterfall" to a smolt and is actually safer than going through the Locks. The cords strung across the spill basin help increase smolt survival by detering seagulls from diving down to feast on the young fish. The smolts remain in the lower basin area for a few weeks acclimating, feeding and growing before they continue their journey to the Pacific.

The term smolt comes from the word "smoltification" which is the biological process the juvenile fish go through which enables them to make the transition from fresh to salt water.

For more info, check out the USACE release on the installation of the smolt flumes.

Note: The fish ladder will be closed June 1-11 for its annual cleaning in preparation for the return of the salmon. Stay tuned!