Pacific
Region North Coast
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Babine River Counting Fence
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Large
Chinook Daily Counts 1990 - 2007 - [HTML]
[PDF]
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Daily
Coho Counts 1990 - 2007 - [HTML]
[PDF]
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Daily
Pink Counts 1990 - 2007 - [HTML]
[PDF]
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Large
Sockeye Daily Counts 1990 - 2007 - [HTML]
[PDF]
The Babine River Counting Fence
The Babine River salmon counting fence is located one kilometre
downstream of Nilkitkwa Lake, 360 km from the commercial fishing
boundary at the mouth of the Skeena River. The counting fence
was established in 1946 and is used to provide an accurate escapement
count of sockeye and other species of salmon entering Babine
Lake, where up to 90% of the Skeena River sockeye are
produced in any given year.
The counting fence is normally installed in early July depending on water levels in the
Babine River. Installing the fence entails positioning 66, 4 by 7-foot aluminium panels in
their respective places along the 330-foot frame that spans the entire width of the Babine
River. Seven holding traps, approximately 6 feet wide by 8.5 feet long are spaced across
the river on the upstream side of the frame. After all the panels are in place, each of
the seven traps is made operational by positioning sliding doors and counting chutes.
All species of salmonids are present in the Babine River with sockeye being the most
numerous. Large numbers of pink salmon are also present and spawn directly above the
counting fence. When post spawning mortalities occur, the fence soon becomes littered with
their carcasses, which are subsequently pitched over the fence. The fence is opened to
allow fish through from 0600h to 2200h daily and counting between these times is performed
in a series of two hour shifts by two, three, and sometimes, depending on the strength of
that days run, four persons. At the end of the salmon migration, the aluminium
panels are removed and the camp is closed down.
Sampling
Every day of the migration 25 sockeye are randomly removed from the traps for the
purpose of sampling. The procedure consists of sampling for sex, nose fork and hypural
lengths and general age, size and sex make-up of that years migration, therefore
enabling potential egg deposition to be estimated. Chinook salmon are sampled after
spawning as they are removed from the fence during that days deadpitch. All chinook,
with the scarce exception of those that are badly decomposed are sampled for scales, sex,
nose fork and hypural lengths, origin (hatchery or wild stock by adipose fin) and in the
case of females, egg retention. Pink salmon are sampled for sex and nose fork length. As
is the case with chinook, pink salmon are easily recovered from the fence during that
days deadpitch and it is at this time that the 100 daily samples are obtained. An
effort is made to stop and sample each coho with a missing adipose fin for scales, length
and sex.
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