A contributor to the Skipton Angling Association’s Facebook site has asked the question, “What should the restocking policy be on the River Aire now that the introduction of fish farm reared diploid brown trout has been outlawed?”

There are three possibilities: 1 Leave the river to be stocked by the existing native fish.

2 Stock with fish farm reared brown trout produced from the eggs and milt of native Aire trout.

3 Use sterile triploid brown trout from fish farms.

The first option would probably see a gradual decline in the trout population as the river’s tributaries have suffered greatly over the past 50 years.

Becks that once held massive heads of trout such as Broughton and Eshton Becks are a shadow of their former selves and would contribute little in the way of new fish for the main river.

The second would be a good possibility if it was up and running as the fish would probably cost no more than diploids do.

The gene strength of fish that survive to spawn would be ideal. Some of these fish may be available in a year or two as at least one local fish farm is looking to try to rear these native trout.

Sterile triploid trout, option three, are already available but have two distinct disadvantages. They cost at least 15per cent more than the diploids they replace and because they cannot breed, they have the same roaming instinct as rainbow trout do when introduced into rivers.

On the plus side, if they do remain in your stretch of water, again like rainbows, they grow very fast and are supposed to be good fighting fish.

I often wonder if the crop of big trout that has materialised in recent years in the local length of the Aire, are the remnants of a batch of triploids that the Skipton AA introduced a few years ago.

One contributor to the Facebook page suggests that the association should introduce triploids to be fodder for pike, mink and otters and thereby reduce the odds of natural brownies being caught by these predators. That would be a somewhat expensive experiment!

Faced with the 2015 ban on diploids, a good number of clubs in the north of England ceased restocking and together with a complete ban on removing natural brown trout, or at least a reduction in the size of the limit bag, waited to see the results.

Surprisingly, most fisheries have seen a big improvement in both the quantity and quality of the fish so perhaps that is also the best solution for the River Aire.