Monday, May 04, 2015

Subtle differences.

Looking at the photos of the little silver fish I caught in Eyemouth Harbour last week I noticed that a couple of them looked subtly different to the others. After doing a bit of research I now think the two fish in question may not have been sea trout. Here they both are.

Two little silver fish. With both note the small mouth, single large spot on the gill plate, the long pectoral fin (more obvious in the first photo), the lack of spots beneath the lateral line, the plainly coloured adipose, pelvic and anal fins and finally the forked shape of the tail. On the second photo note the markings on the flank towards the tail.

Comparing them to these fish which are most certainly sea trout.

Note the larger mouths, multiple spots on the gill plates, the short pectoral fins, the spots below the lateral line and the less deeply forked tail fin. On the first fish note the red colouration on the adipose fin.

Then consulting the following very useful drawing that can be used to distinguish salmon parr from juvenile brown trout.

Salmon parr top and brown trout below. Salmon parr have (a) a sharper snout, (b) a smaller mouth, (c) only one to four spots on the gill cover with often one larger one, (d) a longer pectoral fin, (e) highly defined "parr marks" and no spots below the lateral line, (f) plainly coloured adipose, pelvic and anal fins and finally (g) a deeper pointed tail.

I have come to the conclusion that both of them were in fact salmon smolts. Obviously I'll be quite happy if I am correct as it will be another species towards to my fifty species from Scottish saltwater challenge but before I amend my catch records I'd welcome any comments on my identification of these two fish.

Tight lines, Scott.

8 comments:

  1. I think your right Scott.

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  2. Think you're right there Scott.

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    1. Thanks Martin. Have you ever caught a salmon (at any stage in its development) whilst fishing for sea trout in the open sea?

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  3. Also I agree, I am pretty sure those are salmon.

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  4. No, but I did have one fish off the Tay estuary that caught my eye a few years back, will try and find the picture.

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    1. The life cycles of both species are quite complex and also fascinating. Look forward to seeing the photo if you find it. :-)

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