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Skeena Tyee Test Fishery
 In-Season Sockeye Escapement [HTML] [PDF]- In-Season Daily
Salmon Indices [HTML] [PDF]
- Daily Salmon Indices [HTML]
The most up to date
Skeena Tyee test fishery data is available here:
http://www-ops2.pac.dfo-mpo.gc.ca/xnet/content/salmon/testfish/sockeye/tyee_gillnet.htm
You may be prompted to register for a free account to
access the website.
This old site will be updated occasionally through
the remainder of the 2011 season. It is the intention to have the new
website as the only source of Tyee test fishery data on the web in 2012.
Please forward any comments or concerns regarding the new website to peter.hall@dfo-mpo.gc.ca.
Tyee Test Fishery
Gillnet test fishery
operations have been conducted at Tyee in the lower Skeena River since
1955, in order to evaluate the magnitude of Skeena River salmon and
steelhead trout returns.
This program was
developed to provide daily estimates of sockeye escapements through the
commercial fishery. The data obtained from this operation, combined with
estimates of the commercial catch in Area 4, provides a complete picture of
the sockeye and pink runs as they develop each year. This information is
considered essential for the effective management of all Skeena salmonid
species.
The estuary of the Skeena River exhibits the greatest tidal
fluctuations on the Canadian Pacific coast. Tidal differences of over six
meters, common during spring tides, generate tidal currents of three to
four knots in some areas. Debris-carrying tide rips, unusual current
patterns, and sandbars make the setting of a commercial length gillnet in
the Tyee area a very difficult procedure. The net is allowed to drift
within a channel measuring two to five kilometres
long and 0.8 km wide that runs parallel to the northern shoreline of the
river.
The net that was used
until 2002 in the Skeena test fishery is an undyed,
fibrous nylon gillnet of 200 fathoms total length and 20 feet depth, made
up of ten equal length panels of mesh sizes 3.5 inches to 8 inches. Starting in 2002 a new net has been used based on the popular 6
strand "Alaska Twist" net used by commercial gillnetters.
Set times for the Skeena test fishery vary according to
two parameters. The first of these is the tide height, i.e. the height of a
particular tide above Chart Datum. The second factor is the discharge of
the river. Spring freshets generally reach their peak in the month of June
and taper off gradually throughout the summer.
Sets are made on both
high and low water slack during daylight hours. This usually results in
three sets a day, but sometimes only two can be made. Drifts must be
exactly an hour long.
Daily escapement
estimates are calculated for sockeye salmon. Although they are not
calculated for the other species (chinook, coho, chum, pink and steelhead), relative abundance
and timing is determined by comparing the calculated indices for a given
year to those recorded in previous years.
Problem understanding
the indices? Click
here for assistance.
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