If you live somewhere (like me) that permits the use of one hook and one hook only on your fly patterns, you must be diligent in deciding exactly where the hook will be positioned on larger flies. Streamer patterns with hooks tied in tandem are effective as your chances of hooking fish are greatly increased regardless of how the fish eats the fly, but what if you're limited to just one?
First, let's look at how predators eat their food...
If I were a predatory species such as a bull trout, and I wanted to make mince meat of a small coarse fish such as a sculpin, what would be the safest and easiest plan of attack? Immediately you might think that devouring the fish tail-first would be the obvious option, but there is one major inhibitor to this: digestion.
If I were this bull trout (which I'm not, although I'd imagine life would be pretty fun if I were), I would obviously need to digest my food properly in order to continue doing important things like feeding and existing.
The only problem with eating my meal tail-first? When that spiny little sculpin notices what's going on and immediately flares his dorsal and pectoral fins, I'm going to get a throat full of spiny rays. On top of this, the sculpin will literally not go any further until it retracts its fins.
Hmm... what if the sculpin were eaten head-first?
Let's use the same predator and prey scenario, but imagine that the spiny little sculpin were eaten head first. The sculpin will do everything in its power to flare its fins and keep from becoming eaten, but since it is facing the wrong direction its primary defence mechanism is now rendered obsolete.
Heading towards the bull trout's stomach head-first, the sculpin will inevitably slide down the throat with little chance of escaping. Have you ever caught a predator species with another fish in its mouth? Was it the head or the tail sticking out towards you?
The premise of this example is that predatory species have to digest their prey headfirst unless they are small enough to swallow them whole regardless which direction they're eaten!
What does this mean for hook positioning?
While I originally kept the hook at the back of the fly when forced to clip one from an articulated streamer, this changed after spending more and more time chasing predator species (especially sight fishing in clear water). About five years ago, I started clipping the rear hook off and fishing articulated streamers with only the front hook.
The results have been excellent, there is no part of me that thinks I would be better off fishing for predator species with just the rear hook. Of course, there is no right or wrong and this is simply one person's opinion. This is an enjoyable topic, and one that I think deserves attention in fisheries that only permit one hook!
Want to further your education on fly selection? Grab a copy of The Ultimate Guide to Fly Selection HERE.