It's an interesting wee video but I think it's a snapshot of a much bigger story which the thread title 'to stock, or not to stock' doesn't fully cover.
I am no guru on the subject but I have a rudimentary knowledge based on looking at the history of the Montana rivers stocking policy as part of a college project that (ultimately) didn't get off the ground. Beer, women and fishing all got in the way.... what can I say
I was 19 at the time.
More accurately the title of the thread might be 'what not to stock'. There's huge history here and I'm attempting to bring this into some short perspective but, as I recall, the upshot was that fish were being stocked because everyone thought it was the right thing to do.... but these were all takeable size sport fish with the angler in mind. There was no thought given to what and how stocking was being done, it was indiscriminate and on a vast scale.
The video shows what happened - they canned the whole idea of stocking sport fish of a takeable size based on the evidence of the study.
However.... they have
never actually stopped stocking.
What the department stocks now is the change and even today they plant out juvenile fish bred (as far as is possible) from native stock. Instead of stocking for the angler in rivers the hatchery programme produces fish for stocking lakes bred from native stock and significantly are used to save and stabilise the populations of rarer strains of fish that previously were perhaps ignored.
So what, where and how they stock have changed - but they
still use stocking as an integral part of an organised programme of fisheries management.
H