Tuesday, 7 October 2014

Provincial Framework for Steelhead Management in BC

The Ministry of Forests, Lands and Natural Resources Operations released a document for steelhead management in July of 2014. Intended as a high level document, the policy sets province-wide standards that will be used to interpret and implement local management efforts in specific areas of the province. See: http://www.env.gov.bc.ca/fw/docs/ahte/provincial_framework_steelhead_management_bc_july_2014.pdf.

The province has to produce enhancement efforts in the context of a wild steelhead based fishery, taking into account different stakeholder interests, and in the context of salmon harvest in both saltwater and freshwater, that have differing levels of mortality for steelhead. The primary focus is to provide recreational and aboriginal, fisheries consistent with long-term sustainability of wild steelhead populations.  Then there are the exceptional fisheries that are classified to make them retain peak experiences. The report points out that it also has to be considered that there are alternate freshwater retention fisheries supplied by the Freshwater Fisheries Society of BC.

The important word is ‘wild’ because enhancement efforts tend to reduce wild steelhead numbers, and most of coastal waters, with notable exceptions like the Skeena and its world famous tributaries, like the Sustet, have populations seldom exceeding 100 to 200 adults in a wild run. Maintaining genetic diversity is its own goal, but the context is different runs having different marine survival rates, with environmental shifts lasting a decade, but that can influence recovery or decline for up to several decades.

The document is 29 pages of varying density and will take a couple of hours to read. Two of the appendices warrant your considered look. Table A-2 lists all the summer and winter runs in BC. A Van Isle angler typically considers the east side for winter steelhead and the west side for summers. But the actual runs don’t necessarily mirror common perception. There are only 8 summer runs on Van Isle’s east coast, compared with, as expected, a larger number of populated drainages on the west side, at 23; for winter steelhead, there are 28 on ECVI, but a much larger number on WCVI, at 72. Not expected. But many drainages are short, or have limited productivity areas, say the Franklin, for instance, on WCVI.

Do read the Abundance and Productivity section in the appendices, p20-21, because it discusses natural productivity variables with reference to actual rivers in BC, many of which you will know. A northern BC smolt may take five years in the Upper Sustet to reach smoltification, while in the Chilliwack (aka, the Vedder) it is one to two. The following Status section discusses productivity over time – as much as several decades. And the counterintuitive inverse pattern of abundance in the 1980s and 1990s for northern and southern stocks.

There are over 400 stocks of wild steelhead in BC. Stocks north of Bella Coola improved in numbers in the 1980s and were considered healthy in the 1990s. Southern stocks doubled in size in the 1980s but suffered severe declines in the 1990s with many reaching the extreme conservation concern, for example, the Englishman. Surprisingly, the declines were most extreme in southern ECVI rivers with enhanced runs – leading to the conclusion that enhancement can only be justified in terms of providing a retention fishery for anglers. Then, in 2009, numbers for some southern Van Isle rivers began climbing, including the Cowichan. Knowing the rest of the rivers of this group, and that they are very wild and fragile, I leave it to you to look them up yourself.

Appendix 5 lists the annual hatchery-delivered smolt release figures for Van Isle rivers and the rest of BC. The Stamp, for instance was 70,000 winters and 30,000 summers in 2013; the Quatse and Cluxewe winter numbers were 15,000 and 20,000 respectively.

Of interest, some steelhead runs show a shift away from anadromy at low abundance, meaning they residualize as freshwater residents. Having caught steelhead of 1 – 2 pounds in many VI rivers, I have often wondered about their origin. In the Big Q, a hatchery river, May can be an exceptional month for bushy, white, dry Mayflies for obviously sexually mature ‘rainbows’ of diminutive size, which as most reaches of the river are easily reached and are empty of these fish throughout the year, may suggest a localized, short saltwater phase.

You may be surprised to know that the long-term counting fence facility on the Keogh River provides the only direct measure of marine survival for steelhead in BC. Of course, the angler survey has collected data for a long time as well – since 1967.

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