Size of released sewin

[Tudor]

Can anybody explain the thinking behind what size a sewin should be when returned?
I read somewhere that the larger ones should be put back (over 20'' I think)
Is it that they are more likely to produce more offspring than their smaller brothers and sisters?
If this holds true for sewin, then why not for salmon as well?

[Teifi-Terrorist]

Can anybody explain the thinking behind what size a sewin should be when returned?
I read somewhere that the larger ones should be put back (over 20'' I think)
Is it that they are more likely to produce more offspring than their smaller brothers and sisters?
If this holds true for sewin, then why not for salmon as well?

I am certainly no expert Tudor, but this would be my input:

The 20" (50cm) example is something Llandysul Angling Association implemented last season – this equates to a fish of around 3.8lbs and larger being released. This was to protect some of the larger spawning fish, especially since the nets catch only those of around 2.8lbs and above, so a greater need to protect those that did make it through. A measurement is much better than a weight limit, as I can assure you this is one instance where those looking to dodge the ruling would underestimate the weight of their catch. There is no question when it comes to overall length, which is easier to gather than weight too in order to quickly release a fish that falls outside of these parameters.

As a rule, the larger fish tend to be females (probably on a ratio of 2-3 if not larger) and obviously the larger the female the greater the amount of eggs she carries (similar to that of salmon; around 800 per lb). A small male can still fertilise a large female.

Protecting these larger specimens not only means more eggs and offspring but also safeguarding large fish genetics. There is a cut-off point, however, where the fertility rate of, for example, double figure sea trout would be in question (can depend more on age than weight, as some fish would have gained this weight a lot younger, so will still be very fertile), with the 3-8lbs fish being of particular and most benefit. Again, sadly the size targeted by the coracle and seine nets.

On the plus side for those that do like to take a fish or two (me included, and these measures are always about sustainability rather than 100% C&R) the fish below the 20” measurement are the best for the table.

As for salmon; quite possibly and more likely than not. A lot of the arguments ring true for the salmon. However, on Llandysul Angling Association, for example, we now have a week limit of 1 salmon and a season of 3 (these are carcass tagged). In addition, with the nets ceasing on the 31st of August, they tend not to impact the salmon as much as they do the sea trout runs. I cannot see why someone would want to kill for example a 15lbs+ salmon, but at the moment they can do so. Perhaps this will be reviewed in the future, but there is nothing on the agenda.

TT.

[Tudor]

Diolch TT am dy ateb.
Lot o wybodaeth gen ti i'r cwestiynnau.

Thank you TT for getting back to me. A fount of knowledge and information as usual. The only thing now is for me to catch one, regardless of size!
Tudor

[Mick B]

There are some very good scientific papers on this subject.
They all support the release of large fish.

The reasons presented are that;
a) In fisheries where the largest fish have always been removed the size of the fish captured in future years has always gone down and down.
b) large females produce more and larger eggs, these eggs hatch quicker and the juveniles develop faster and attain maturity at a young age.

Also, eggs produced by fish are not proportionate with the size, a 5lb female does not produce 50% of the eggs of 10lb female, the number is more like 15-20%.

Sadly netting policies are usually set by the commercials (with assistance from Government agencies) with little regard for sustainable long term fisheries, its the same the world over, profit now and ignore investment in the future. ::

[T7]

1.5-2.5lb sea trout is perfect for the table. I've not killed anything bigger than that for many years and usually take only a couple per season (if I catch any!)