Cal Gates started Gates Au Sable Lodge east of Graying at Stephan Bridge in 1970. Only three years later we held our first Fenwick Fly Fishing School there. Cal became a great friend over the years and when he died, Rusty and his wife Julie bought the Lodge from his mother, Mary. Rusty was still a teenager when I first met him, and over the years, both Jason and I came to know him well. He was always helpful to us during our schools, and provided a great location for class-room teaching and on-stream presentations.

Rusty was first and foremost an avid, almost rabid, defender of the quality of his beloved Au Sable. He fished it extensively and knew it better than anyone I know. He was noted by both conservationists and anglers on a local, regional, and national level. Rusty developed lung cancer several years back and fought it valiantly, now he is gone, and all of us are poorer because of his passing. Good bye, old friend.

Rusty Gates fishing his beloved Ay Sable.

A standard drawing of a fish clearly indicates that there’s a blind spot just in front of the fish’s head because the fish’s snout is in the way.

The position of the forward blind spot is just in front of the fish's nose. Artwork by Jason Borger

However, there are three other factors that must be considered. First, the fish’s eyes bulge out from its head a bit, and that makes the blind spot shorter that a simple drawing would indicate. Second, the fish can actually move its eyes, rolling them a bit inward and forward to see items right in front of its nose more easily. Third, the fish has a sighting groove or notch in its nose to further minimize the blind-spot effect of having its eyes at the sides of the head. All in all, the blind spot is greatly reduced. It’s not totally gone, but by the time any food item enters the minimal blind spot, it’s so close to the mouth that all the fish has to do is open up and eat it.

This is not really all that different than the blind spot that we have in front of our mouth. We still get the fork in there with startling regularity. Unlike Steve Martin in “Dirty Rotten Scoundrels,” we don’t have to have a cork on the fork to keep us from stabbing ourselves. Maybe a cork to keep us from eating so much, but that’s another story.

The sighting groove or notch is clearly seen in this 12-inch brown.

The reason for placement of the eyes at the sides of the head in fish is to increase the animal’s peripheral vision—that area seen only by one eye. The fish’s peripheral vision field is 330 degrees; ours is 179 degrees. This means that fish see objects behind them, which is very good for a prey animal. On paper, a drawing like the one below would suggest that there’s a blind spot behind the fish of 30 degrees and a tiny one in front of the fish’s nose where it cannot see with either binocular or peripheral vision. As we shall see, such is not really the case—but in a later post. Today, I want to focus (pun) on the fish’s peripheral vision.

This portion of vision is highly sensitive to contrast and motion; in other words, it’s the predator detection zone that allows the fish to notice critters trying to get up on its back side and grab it. When the fish is looking at the currents trying to find food and something suddenly enters the peripheral zone to the side or behind , the fish takes off for cover—at least the ones that survive to pass their genes on head for cover. The rest of them go down the gullet of a bird, mink, otter, etc. This has great import for the fly fisher, who for some reason, insists on tossing that fluorescent line and shiny leader  high in the air so that all fish can have an equal chance of seeing it—perhaps they want to give the fish a sporting chance.

The fish's peripheral zone is 330 degrees, it's binocular zone is 30 degrees. Peripheral vision is especially enhanced to detect contrast and motion--it's the predator detection zone. Artwork by Jason Borger

Like hot race cars, fish sport a pin strip down the length of their bodies. It’s the lateral line–lateral meaning “side.” It may be distinctly darker than the side of the fish or it may only be seen as a raised area along the side. The  lateral line consists of a series of interconnected “U” shaped tubes filled with a jelly like material. The open end of the “U” is facing to the exterior of the body. The lateral line extends forward around the fish’s eyes and on its lips, although in these areas the structure is much more difficult to discern with the naked eye. Nerve endings line the bottoms of the tubes. Waves in the water generated by displacement (a minnow swimming, an angler wading, and so on) create pressure on the material in the lateral line. This pressure is sensed by the nerves. It’s a very sensitive structure that not only allows the fish to detect prey and predators but also allows the fish to align itself most advantageously in the currents, to space itself in a school of fish, and to swim with the synchrony of the school. The lateral line can detect differences in currents between the two sides of the fish’s body  as small as 1/25 of an inch a second.

Have you ever wondered how fish are able to just sit there on the bottom is a fast stretch of water and not have to swim to do so? Well, they can easily find the places where the currents will allow them to park without having to work. The very first and single most important rule about reading waters is that fish cannot hold in fast currents. They simply cannot swim endlessly. If they could, one would never land them without simply forcing them to shore. Fish rely on the lateral line to help them find that just right spot to stay out of the currents while looking for food or hiding from a predator.

Speaking of which, Mr./Ms. Predator, trudging along the stream bank like an elephant in a congo line is not smart. The pounding vibrations of one’s feet transfer directly into the water as displacement waves, and fish pick up on it immediately. They either flee or they zip up their lips and sink to the bottom. Walk like a stealth heron, and stay hidden. Always assume that the fish can both see and hear you. And for goodness sake, wade quietly. There’s a saying that goes like this: Fish know you’re in the water, big fish always know. If they can hear you hiking on shore, they can certainly hear you waltzing around in their living room.

A South American Payara—note the very easily seen lateral line; the better to hear you with , my dear. Note also its very large eyes; the better to ...

In addition to a running discussion of fish ears, I want to talk about fish eyes, too. There are a number of questions that keep coming up relative to fish vision that tell me the pool of misconceptions is still deep, dark, and slow moving. Here’s the much compressed lowdown on fish vision. These items will be expanded as we go forward.

1. Fish see in color.

2. Fish vision is not as detailed as ours (ours is not as detailed as an eagle’s).

3. Fish can move their eyes (just like we can move ours) and they can move them independently (we have a very hard time doing this).

4. If you can see the fish, it can see you.

5. More to come.

Let’s start the whole discussion with a look at the positioning of the fish’s eyes. Humans, lions, tigers, and bears, oh my, have their eyes facing forward because they are at the top of the food chain—predators, all of them. The eyes in the front give them excellent binocular vision (ours is about 90 degrees) so they can better see their prey as they race after it. Fish, gnus, deer, cows, and the like have their eyes at the sides of the head so that can keep an eye on the predator behind them. This restricts their field of forward binocular vision to about 30 degrees.

Conclusion: You’re a predator, start acting like one because the fish is prey, and they most certainly act like it.

The fish's eyes are at the sides of the head "the better to see you mine otter." Their field of forward, binocular vision is only about 30 degrees.

Fly fishers have spent an inordinate amount of  time studying the visual acuity of trout. That’s good because it has given us some remarkable data that have helped shape not only our flies but also our angling tactics and the clothing we wear. But, in the process, we have neglected the acoustic acuity of fish. I think this has happened largely because most fly fishers fish for trout with insect imitations, Insects don’t make a lot of noise, even when the stamp their feet. But, minnows, frogs, tadpoles, leeches, mice, big dragonfly nymphs, and other large creatures certainly do. Their swimming motions displace water and fish can sense that with the lateral line. Flies that push water are far more effective when imitating these water-pushing organisms than are slim, profile-only flies. There are some excellent data available to us on the acoustic footprint of organisms and flies, and we will investigate these from time to time on this site. Watch for upcoming posts, In the meantime, start thinking about fish hearing as well as seeing their food.

Trout have ears--OK so they don't look like this, but they can hear very well, and anglers need to pay attention to the fish's acoustic acuity.

The Blood Knot is an excellent way to connect two pieces of monofilament. It’s thin in diameter and very clean (no protruding bits to catch weeds or other obstructions). Back in the days of gut leaders it was the knot of choice. When nylon appeared, the Blood Knot hung on, but with the same restriction that it had in the days of gut: it is not good for connecting pieces of mono that are more than .002″ different in diameter. This meant that an angler building a leader down from .020″ to 3X would have to connect .020″ to .018″ to .016″ to .014″ to .012″ to .010″ to .008. Whew, that a lot of knots. I can personally testify to the difficulty of following a leader formula that had 7 pieces, some of which were only 6″ long. Ugh! As I experimented with nylon, I realized that its properties were as different from gut as day is from night. They are simply not the same in any way except that one can get them in a variety of diameters.

In the olde dayes, if one reduced the diameter of the gut sections by more than .002″, hinging would occur. That is, the thinner section would collapse back onto the thicker section. Not so with nylon. One can reduce the diameter of each subsequent section of nylon in a leader by 35% and not get hinging. That means you can connect .020″ mono directly to .013″ mono and not have a hinging problem. Now a leader can go from .020″ to .013″ to .010″ to .008. Fast and efficient. Oops, the standard Blood Knot can’t make the jumps.

Here’s the problem. When the material only varies by .002″ the five coils of mono on each side of the knot pull up smoothly and evenly. When one exceeds this .002″ rule, the thin material pulls up faster than the heavier material, and the knot can’t come completely tight on the heavier material side. As I experimented with  the knot, I discovered that as the diameter difference increased beyond the allowable .002″ more turns were required with the thinner material in order to make a strong knot. In fact, for each .002″ beyond the allowable, initial .002″, one more turn was required by the thinner material. Thus, when connecting .020″ to .014″ (a difference of .006″) the knot is perfectly balanced using 7 turns with the lighter material and 5 with the heavier material; thus, the 5/7 Blood Knot.

The reason, it turns out, is that the 7 turns of the lighter material takes the same amount of time to turn over and pull up as does 5 turns of the heavier material. Furthermore, once the 5/7 knot is tight, the distance from the center of the knot to each end of the knot is the same–the knot is balanced in the way it tightens and in its size from the center to each end.

5/7 Blood Knot--5 turns with the heavier material and 7 with the lighter material. Lubricate the knot before pulling tight. Artwork by Jason Borger

My friend, Ozzie Ozefovich, has been shooting underwater footage of trout for years, and has produced a couple of revealing DVD’s on the life and times of trout. His latest DVD will be released later this month. Entitled “Trout Vision and Refraction,’ it is an excellent look at these phenomena. The underwater shots through the fish’s window are most revealing. I’ll keep you posted on the release date.

These are two photos I shot in NZ in the early 1980’s of an angler 25 feet away from above water and underwater through the window. This will give you a taste for what’s coming from Ozzie.

Mike casting on Siberian River in New Zealand

Mike as seen when looking up through the fish's window. Where are the rocks, the mountains, & other background objects? Is that an extra leg I see? He looks a bit squashed.

The first draft of Volume 1, “Fishing the Film” in our book series entitled Fly Fishing has been submitted to the editor for his comments. Fishing the film deals with all aspects of this feeding zone, both above and below, as well as in, the surface film. Fishing the film is not always what it seems, as the story below so clearly documents. The parenthetical phrase in italics just under the title of the story lists the tactics illustrated in the story

Dry Enough, Indeed
(Across Stream, Up and Across Stream, a Switch Cast, a Angled Pile Cast, the Reach Mend, and the Greased Leader Tactic)

Angler’s the world over consider them hallowed waters because it was here that the written world of fly fishing began. Most of the early trout tactics were codified on these waters, and it was here that Fredrick Halford plied the dry while his gentlemanly rival, G.E.M. Skues taunted him by taking trout on the nymph. It is on rivers like the Test, the Itchen, the Kennet, and other chalk streams in the south of England, where the foundation stones for fishing the film were laid.

And so it was with great delight that Jason and I were sharing a day with our great friend, John Goddard, on his beat on the Test. Jason and I had some video work to do on “Where the Trout Are,” produced in cooperation with the Federation of Fly Fishers, and so John was fishing and we were shooting and trading the rod. We could see John upstream fishing away as we slowly made our way along. Video work is tedious and takes about ten times as long to shoot one fish being caught as it actually would take to catch it, if one were fishing without the need to please the camera.

On one corner, I spotted a trout working across stream in an eddy formed where the currents pushed against the bank and slid out along the trunk of a downed tree. It was an awkward spot because it was overhung by trees and closed in behind with brush and high vegetation. A roll cast across stream was immediately met with a skating fly. The currents were stronger than they looked. Time for consultation. We talked about the situation, pointed out the currents and how the line should best fall, where the fly had to ride, and of course, how in the blazes were we going to get the line to do that, given the trees and brush all around us. We decided on a Switch Cast. The Switch would give extra line speed to be certain the Angled Pile Cast would flip over properly and dump a pile of slack out there just above the slowly rotating, reverse currents. As the line flipped over at the tip, I reached the rod out as far as I could toward the middle of the stream, trying to get that shallow downstream angle that we both agreed was necessary. It took four or five tries to get the line on exactly the right current tongue, but suddenly there was the fly doing precisely what we had hoped. Up came the 18-inch brown and ate it with aplomb. We were elated. It was a much Jason’s fish as mine.

We worked upstream toward John, and came to a long straight stretch of water in an open meadow where fish were rising with regularity. Cast after cast was rejected, or didn’t even get so much as a nod. The elation we had felt over solving the puzzle of the fish in the corner began to deflate. John was a hundred yards away, and as we watched we saw him land a nice fish. He released it, straightened, rubbed his fingers along the leader, made a cast, and was fast to another. By the time we had walked up to where he was, he had landed that one and hooked a third.

“What the heck are you using, John,” I called out as we got close.

“An emerger just under the film,” came his distracted reply.

Jason and I looked at each other. John had told us this was dry-fly-only water. “An emerger under the film,” I said a bit in disbelief, “I thought this was dry-fly-only”?

“It’s dry enough for me,” he chuckled.

We’d been had! John was fishing an emerger just under the film with the Greased Leader tactic, playing Skues to my Halford.

“Dry enough, indeed,” was all I could manage to mumble back.

The brown from the corner, taken on a real dry fly

My great friend John Beth was at it again. While the rest of us ate turkey and stuffing, John was busy stuffing a big streamer down the throat of a 33 x 20 female brown (20 x 20 x 33/750 = 17.5 lbs). That’s quite a collect of big browns for Johnny Boy this fall. If he keeps at it we may have to call him a hog fish hog He deserves these big fish, however, because he works hard to get them. He only saw 2 big browns and 1 small one. Way to go, my friend.

John Beth & his 33x20 female brown (17.5 lbs.) Great late season fish!