I'm not really in a brigade, and I haven't suggested otters decimate rivers. I did, though, post voicing concern that otters have been appearing on a small big-river tributary which is of borderline status, with only small pockets of eg medium size chub and a history of being knocked back to square one by happenstance. I doubt that any aspect of this river, which limps along in the margins of our neglect, has been subject to academic study, although a friend did qualify in aspects of fishery management via a habitat study based on it. My concerns were that otters visiting to hunt from a nearby big-river base to exploit what might be a thinner population of prey fish but easy pickings, or living temporarily along it while they find out if it's viable as a place to live, may impact on the stocks. We have waited a long time for some recovery in this little river, and this depends on successful spawning by the small numbers of fish present. It may not be demonstrated in an academic paper, but isn't it quite possible that the number of fish might be reduced, and the recovery set back yet again, if, to add to all the other problems, they are being predated by otters, even if the habitat eventually proves inadequate to support otters, or the otters being seen are travelling up it to hunt whilst living on the main river? Would you agree that such things are possible? I set the possibility against the general pro-otter claim that everything levels out ok in the end. We are seeing a process that is new happening, and I don't see any guarantees that everything, while otters recover old territories or test out and find new territories, will pan out without sacrifice of things like the recovery of the small river in question. I quite get why some will be irritated by overstatement of destructive predation; it's also irritating to have any concerns about otters dismissed as mere prejudice or ignorance, not that your post suggested this.