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SSRAA's Summer Coho
Program
PROJECT LOCATOR: Neck Lake is on the
eastern coast of Prince of Wales Island draining into Whale Pass. The
island is characterized by steep forested mountains where 60 to
200 inches of rain falls each year. You can drive to Whale Pass from
the Craig/Klawock area on Prince of Wales or travel by boat or float
plane from off island communities. SNOW PASS COHO:
Snow Pass Coho are summer coho that currently return to both Burnett
Inlet Hatchery and Neck Lake. What is a summer coho? A summer coho is
a true coho that behaves like a sockeye. There are several small stocks
of these fish in SE Alaska. They return to lake systems in early summer
and ripen for spawning for several months in the deep cool waters of the
lake. They enter tributaries of the lake and spawn at the same time the
more common fall coho enter streams to spawn. The Snow Pass fish
originally came from Reflection Lake in Behm Canal and are now reared at
Burnett Inlet Hatchery and in Neck Lake. These fish are generally the
first coho to enter the market each summer.
EGG COLLECTION:
About 2 million eggs are collected and fertilized each year at Burnett
Inlet Hatchery from adult fish returning to that site. After the fry
hatch about 1.6 million are moved by plane to net pens in Neck Lake
while 200,000 are retained at Burnett Inlet as broodstock for the coming
generation. The fish retained at Burnett Inlet are reared at the
hatchery for a year and then released as yearling smolt weighing between
25 and 30 grams.
NECK LAKE PRESMOLT
PROJECT: All the fry moved to Neck Lake are reared in net pens
through the summer and well into the fall of the year. At some point in
November half the fish are released into Neck Lake while half are
retained in the pens. At this point the water in Neck Lake is very cold
and the fish enter a dormant state somewhat similar to hibernation with
mammals. Through the winter the fish in the pens are not fed and it is
likely the fish released in the lake feed very little if at all. As the
water warms in the spring the fish in the pens are once again fed,
likewise the free-swimming fish in the lake begin eating as the
phytoplankton and zooplankton blooms occur. As the fish change to ready
themselves for migration to saltwater, a change we call smolting, we
release the fish from the pens. At this point the coho leave the lake
over the small barrier falls at the outlet of Neck Lake and move to
saltwater in Whale Pass and then Clarence Straits. From there they move
quickly through the SE Alaska archipelago and to the open ocean where
they remain for 14 months. After 14 months at sea, those fish that have
survived will return to the systems they left as smolt, some going to
Burnett Inlet while the majority of the fish return to the small stream
below Neck Lake.
THE NECK LAKE
FACILITY: Water from Neck Lake flows through a pipeline and into a
single large raceway below the barrier falls. The falls prevent adult
coho from entering the lake. The fish are attracted into a fish pass at
the base of the falls and climb to the raceway where they are held.
RETURNING ADULT
COHO: The first Snow Pass Coho returned to Whale Pass in 1998.
Large numbers of these fish are harvested annually in traditional
commercial gill net and troll fisheries, primarily on the north end of
Prince of Wales Island, as they make their way back to Neck Lake and
Burnett Inlet. The local sport fishery in Whale Pass gets intense for
about a month as the fish school off Neck Creek waiting for rain before
they move into the stream.
ENTERING
FRESHWATER: Finally, with each low-pressure event, the fish come up
the fish pass in small waves. These fish are unique, they will not move
into freshwater without rain. Week-long periods of high pressure and
sun see large schools build in the lake off the creek. The schools
continue to grow until the weather changes. As the fish sense the
pressure drop, which is usually associated with rain, they begin to move
with the next tide.
HARVEST:
While a full harvest is 4,200 adults, this number is related to the
number that can be transported to Ketchikan in one trip rather than the
number that could otherwise be harvested. If the water is not
excessively warm, the raceway can hold more than 6,000 adult fish. When
there are sufficient fish in the raceway for harvest they are crowded
toward the front of the raceway. The fish in the front of the raceway
enter a hydraulic lift, or fish elevator. The fish in the elevator are
lifted from the water and flow into the harvest line.
HARVEST LINE:
As the fish slide from the elevator they are immersed in a bath that is
supersaturated with CO2. The bath serves to anesthetize the
fish. The fish are quickly removed from the bath and killed and bled.
They then pass through several rinse totes and are immediately placed in
slush ice. A full harvest results in 4,200 fish in 32 totes of slush
ice. When the fish are running strong, we may harvest 3 or 4 times in a
week.
TRANSPORT TO
MARKET: Within several hours of harvest the slushed fish are picked
up by a local trucking firm. The fish are hauled to Hollis where they
are loaded on a small ferry and moved in several hours to Ketchikan.
They are quickly custom processed on the Ketchikan waterfront, placed in
50-pound wet lock boxes, and refrigerated. The next step is to get the
fish to Seattle. In some instances they are flown to customers while
most often they are moved on the Alaska State Ferry System to Bellingham
and Seattle. The fish generally reach Seattle within 36 to 48 hours of
actual harvest. Because of the short time between actual harvest and
the market; these are among the freshest fish in the Pacific Northwest
fresh fish market. Historically, while we expect the numbers to
increase, up to 50,000 fish have been harvested in a summer. SSRAA has
trademarked the name Snow Pass Coho so that customers know what they are
buying when they purchase these fish.
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