Inside Coho

To no great surprise the forecast for coho in southern BC in 2016 released this spring did not make for encouraging reading, amplified by a similar outlook for nearby US origin coho stocks that in general had been enjoying considerably higher survival rates over the past decade.
With certain exceptions, for most of the past twenty years the presence of coho in the Strait of Georgia has been scarce to non-existent until late summer when the maturing fish have been encountered as they head for their home rivers. 2013 was an exception, providing easily the best inside coho fishing of the modern era, with coho around in lesser numbers during summer 2014 although the impression was of more simply because of the ability to retain one wild coho per day.
Once again coho were largely absent from inside waters in 2015 until late summer so against that background it is a welcome surprise to find out about a strengthened presence of coho in the Strait of Georgia this year, starting in early June. They showed up in a wave, apparently from the south or Juan de Fuca Strait direction and between French Creek and the Gulf Islands and over to the lower Sunshine Coast area there were quite a number encountered by anglers. As the month progressed the fish spread up the Strait of Georgia so that by the Canada Day weekend some boats caught half a dozen in a trip around the bottom end of Quadra Island.
Even more encouraging is there’s a moderately strong mark rate in the mix, about 20% on average, adipose fin-clipped hatchery origin coho legal for retention. The number of hatchery coho around in 2016 represents the final year of the latest “normal” production regime, with numbers declining starting next season as the reduced egg-take targets that began in fall 2014 begin to play out in lower numbers of marked fish present in the fishery. DFO is convinced that lower hatchery production – again – will result in higher survival so the net abundance of retainable coho will be the same but personally I have my doubts.
Since the beginning of the mass marking program to facilitate the mark selective fishery for coho in southern BC starting around the year 2000 the numbers of both hatchery produced coho and the percentage that are adipose clipped have both steadily declined, a concern in a predominantly hatchery only retention management scheme.
The Quinsam River hatchery now produces only one-third the coho it did in the 1980’s and the Puntledge River hatchery no longer produces smolts, instead because of persistent high summer water temperatures it now outplants the fry in the upper watershed by early summer, most of which are not fin-clipped. These are but two examples of the trend in Canadian hatchery coho production.
For twenty years it has been quite evident that for more than most salmon species in southern BC coho have been suffering from poor (and sometimes that’s a generous assessment) marine survival during their first six months at sea but increasingly they’re now facing a double whammy because of persistent dry weather during recent summers. The fondness of coho to populate the smallest of watersheds and the low to non-existent precipitation for months on end means that the freshwater survival of southern coho has declined overall as well.
Despite a little more precipitation recently, with certain exceptions once again authorities have closed rivers to fishing across southeast Vancouver Island as the area is now considered to be in a Stage 4 drought – extremely dry. Despite an improved snow pack on island mountains last winter the record heat and dryness during April and May eliminated any hopes of avoiding the extreme low flow conditions now present.
Persistent conditions like these will continue to keep the brakes on any allowed exploitation of wild coho in inside waters for the foreseeable future. Despite this there’s a need to find out what wild stocks are present in the lower Johnstone Strait/Strait of Georgia area and, as importantly, when so to facilitate this a number of anglers and guides have signed up to take tissue samples from wild coho encountered when fishing. With the use of a paper punch a small disc of tail fin can be quickly removed from a live fish without harm before quickly releasing it.
The tissue samples are then sent to the genetics lab at DFO’s Pacific Biological Station in Nanaimo where the samples are run. The genetic map of both chinook and coho salmon in the Pacific Northwest is well understood and even if the exact watershed can’t be determined certainly it can be keyed to the general area e.g. ECVI or lower Fraser.
The hope is that over time a reasonably clear picture of when and where the coho stocks of most concern e.g. Interior Fraser, are present in any given fisheries management area such that opportunities for limited wild retention may occur in future years subject to various constraints. Such fine-tuning would be a big advance over the current almost blanket non-retention regulation over inner south coast waters.
So as I said earlier the fact that coho have showed up around inside waters this summer is a welcome surprise, I hope they keep coming! Meanwhile retention of wild coho at present is illegal around SBC waters with the exception of inside the surfline on WCVI and in parts of area 12. Should you happen to catch one please exercise great care when handling these fish, ideally don’t even bring them in the boat.