Thursday 9 October 2014

Atlantic/Wild Pacific Salmon Crosses

This is the weekly article I wrote on fish that I have caught in the past decade that looked to me like crosses, and the first three mentioned looked like crosses with escaped Atlantic Salmon and wild Pacific salmon. I sent the col,umn to several lists and put it on: www.onfishingdcreid.blogspot.com.

Hybrid salmon – I mentioned last week that one of the fish we caught in Quatsino Sound was a chinook/Atlantic salmon hybrid and this sparked comment. The distinguishing feature was big black spots on the fish’ gill plate, a farmed salmon trait. On the other hand, it had a black mouth and looked and smelled like a chinook. I took it for a hybrid Jack and turned the hook.

This is the third fish in the past decade that I have identified as a chinook/Atlantic cross, all taken from Campbell River north. In all cases I turned the hook, as all were undersized Jacks, and thus not legal to take. I let 99% of all fish I catch go anyway, so would not have taken it if it had been legal.

In addition, I have caught two other odd crosses: a lavender Jack – a cross with a char? – from the North Island; and a Jack with three distinct stripes of grey on a blue background in the Nitinat where there are no Dolly Varden char.

I have an image of an 8 pound summer steelhead from the North Island, that upon looking closely at the images came to believe it was a coho/summer cross, they both being present in late fall. And the most common hybrid on Vancouver Island are cuttbows, a cutthroat/summer steelhead cross. I have caught/photoed dozens of these over the years, as well as seen spawning steelhead populations with lots of small fish, presumably cutthroats or residualized ‘rainbows’.

It was suggested that I should have photoed the Quatsino fish, retained it frozen, and sent it to DFO for DNA identification. Without doubt I will photo such fish in future – I have a waterproof camera and will carry it. And I have sent a note to Minister Gail Shea asking her to authorize me to retain such a fish and forward it to DFO for their identification.

Also commented on, I have two PDFs of interest: more than 7 million Atlantic salmon were released over earlier decades of the 20th century in BC, but as no spawning populations took hold that seems proof they cannot reproduce in BC rivers, hence we catch no adult Atlantics. I have wondered why and perhaps have the reason. Our rivers are severely damaged by logging practices, with shifting mountains of silt and small gravel still being disgorged a century later. We have monsoons of heavy rain in the fall, high temperatures with low O2 in summer and our rivers tend to be of high gradient.

Of the few Atlantic rivers I have seen, all were characterized by large boulders – not gravel – and flat; they received less rain and didn’t look logging damaged. Maybe these differences account for the lack of Atlantic spawning success in BC.

The second PDF is the pairing of eggs and milt from the five species of Pacific salmon, steelhead and Atlantic salmon. The result was negligible numbers of fertilized eggs, which is to be expected. In other words, the chances of hybrids are slim to none. I can send the PDFs to anyone who wants them, and will try to attach them when I put this post on www.onfishingdcreid.blogspot.com.

I would be interested to hear if any reader has also encountered Atlantics, as anecdotally we hear of them. Perhaps I have seen more because I fish more often than the average angler and in many different bodies of water, for example, I have fished 40 different rivers/estuaries on Van Isle as well as saltwater. I may just see more fish. For example, this year I have released about 500 salmon/trout/char, and will probably release another 100 before the end of the year.




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