So, If I'm fishing for four hours and I catch 8 fish, thats 2 fish per hour, right? If they ask 9 other guys how many fish they got and they each got zero, that 0.2 fish per hour, right? It is not an indication of how good the river is.
On the Farmington, fish will rise to take flies, even when there is no real hatch, because there is so little food there (except for the supplemental feeding program, referred to by "the biologists" (more appropriately the political pawns) as the Atlantic Salmon Restoration Program) but I digress. Then when the creel surveyors come around (June through August - when the kids are out of school, and the Housy is typically warm) people are catching fish. Is the river really better? The angler experience is. Some anglers probably count fish they hooked or missed, because the creel surveyors might think they're fools for catching nothing when fish are rising everywhere. Do you think there is some "human element' represented in the truthfulness of the reported results? I suspect there is.
If they have historical numbers, they probably (I do not know this) did creel surveys on the Housatonic during shutdown flows; thats when all "the anglers" wanted to be on the river. Many people would not want to get in that river when it was over 600 CFS. I've had several people tell me that river was unsafe for wading at flows over 1000 CFS. The reality is that many "anglers" want the opportunity to shoot fish in a barrel. These are the same people who will complain that the Farmington is too tough when it's over 400.