On a trip down the mountain to Sacramento, after a month of frustrating fly fishing at Lake Davis, I switched from my local fifty-watt foothill radio station to NPR’s Capitol Public Radio, at times a more intelligent level of discourse. I chanced to pick up an interview with a fisheries scientist who had written a book on fish behavior and intelligence.
Among other things, this author said that certain fish exhibit social behavior. Like higher-order animals, they can communicate with sound, have acute color recognition skills, can find their way through obstacles, and importantly, have memories that can last over a year. He was referring to the greater taxonomic order of fresh and saltwater fishes, not just trout, bass, and panfish. I found it interesting that he mentioned carp are higher up the intelligence scale than many other freshwater fishes (See Seth Norman’s classic story, “A Crime of Passion,” reprinted in California Fly Fisher, July/August 2016).
The subject was relevant, because earlier in the week, I had landed just two trout in three and a half days of angling, trophy-size fish though they were. My boat partner shared my success, or lack thereof. Boat conversations and campfire banter centered on how hard fish had been to catch this year. We knew that trout stocks were down due to the drought and as a consequence of a hatchery water-temperature problem that killed fingerlings scheduled to be planted the past two years, but we also suspected, along with guide friends who are on the lake a lot, that the remaining fish now are larger and wiser. And the gist of the NPR interview was that this order of animals is indeed much “smarter” than previously thought. Sensory perception in the animal world, particularly in higher orders of animals, can greatly exceed that of humans. Their senses of taste, smell, vision, touch, hearing, and perhaps others senses, such as the ability to recognize magnetic fields and star patterns, can be highly developed. Raptors are said to have vision that is 10 times more acute than ours. Salmon follow minute traces of stream scent signatures when returning to their parent rivers. Dogs are used to sniff out bomb ingredients, and some fish can sense human scent on bait. Remember that cute beagle at SFO customs? He found the duck salami that I brought in from France. Another found an achiote spice brick that I was bringing home from the Yucatan.
Animals seem to “know” what is “ordinary” and “normal” and that any deviation from that norm isn’t right. This has been postulated to be the basis of selective trout behavior. Fish reject artificial flies that aren’t the right size, form, and color, locking on to a particular food source, and yet at other times, throwing us a curve, will attack a bizarre attractor fly that doesn’t match normal food in any way. Other factors, such as presentation, are at work, but that doesn’t fully explain it. Selective Trout, by Doug Swisher and Carl Richards, was devoted to tying better insect imitations and dealing with trout selectivity. They popularized the word “selective,” meaning “discriminating,” in angling literature. We know how discriminating fish can be.
For years, perhaps as long as angling literature has been around, anglers have been told and chided by scientists, outdoor writers, and philosophers that the fish we pursue have brains the size of peas. It has been postulated that fish behavior is mostly “instinctive,” the corollary being that there is little, if any, cognitive behavior. Certainly, many anglers have voiced their utter frustration at not being able to outwit creatures with so small a brain. Humans excel at assessing, processing, and acting on information. Fish brains may be pea sized, and their brain-to-body mass ratio is small compared with humans and other higher-order animals, yet they process sensory input in a way that allows them to survive in a challenging environment. Does this constitute “thought”?
At UC Santa Barbara, I studied animal behavior in insect, avian, and mammal populations. This was done through field observation. I took meticulous notes, then tried to interpret my observations, often referring to previous studies in laboratories and scientific literature. Though researchers today are aided by amazing cameras, spreadsheets, satellite tracking, and computer programs that I never had, field observation remains the backbone of this type of research. Fly fishers are empiricists by necessity, and most fly fishers that I know are good, albeit amateur field observers.
Observation of feeding fish in clear water will show that they first recognize a possible food item with vision. Then they approach, and if something is looking good, will ingest it. Videos show that underwater, fish reject or spit out more than they retain. It is reasonable to suspect that they “taste,” possibly “smell,” and “feel” the interesting object when making their final decision. I first observed this in a private showing of a video made by legendary guide and author Jack Dennis, on Flat Creek, near Jackson Hole. Flat Creek is a clear spring creek, yet on close inspection there was lots of material in the water, and fish constantly made decisions as to what was food and what was not.
Not long afterward, I devised an experiment based on this observation. I was at a function at Lake Tahoe. The property held some large trout in ponds. I gathered worms, grubs, caterpillars, beetles, and ladybugs, as well as small pine buds and debris the size of these food items, and, one at a time, I cast these articles where wary, cruising trout that had avoided encounters with bears, coyotes, and raccoons could intercept them. The trout approached carefully, ingested the matter, and spit out all but the legitimate food.
In research, validity is measured, among other things, by the size of the sample. In fish observation in the wild, we are at a disadvantage in that the fish are moving around and are of different age classes, species, subspecies, and strains, and variables are present such as food sources, water temperature, oxygen saturation, pH level, light levels, hour of the day, and the astuteness of the observer. It makes for difficult assessment. That’s why we will always be arguing around the campfire about these issues.
Observations in clear mountain lakes suggest that leader diameter and length make a difference. I have guided on private still waters, and one of the first things that I did for any angler having difficulty was to check to see if they had a leader system that I knew would work. Invariably, on my lakes, adding 3 to 4 feet of finer tippet to a 9-foot tapered leader helped dramatically. All leaders cast a shadow, but does a longer, finer leader lessen the chance of a fish relating a fly to an angler threat? Do fish see the thicker butt sections and the line itself? Do they hear or sense lines being pulled through the water? We had so many rejections on our last trip that my partner asked me to stop talking.
Many have observed that fish that see the fly before they see the leader are more likely to take the offering. Do fish have a way of communicating? “Those red ones will get you in trouble. The ones with the thick clear stuff at the front are fake”? At any rate, one of the most consistent observations that fishing partners and angling friends make is that trout seem to be boat, pram, and float tube shy and to “know” how far we can cast. We have learned that our chances for a take came on good casts when we have added extra tippet and turned the fly over out at 60 to 70 feet. And such behavior seems increasingly to be the case this year.
Does this relate to the fact that at Lake Davis there are mostly bigger fish that have grown up and held over three and four years? We didn’t catch a fish under 19 inches this year — nothing under 21 inches on the last trip. Guide Jon Baiocchi, who is on the lake as much as anyone, reports that the fish have gotten wiser as the season has progressed and that this happens every year. Anglers know that second-year 12-to-14-inch planters that arrived as fingerlings are easier to catch than the big holdovers that have lived years in the lake. Do the big ones have better memories? Stillwater guru Denny Rickards says, “If you don’t get your fish on a first long cast, your chances go down rapidly.” Does the second, third, and fourth cast pique their memory or remind them of unpleasant experiences?
Do fish recognize flies that are used a lot? Years ago, André Puyans popularized his new APBT-PT fly, the All-Purpose, Bead-Thorax Pheasant Tail Nymph. The brass bead is located under the wing case, in midthorax position, not at the front of the hook. The fly has a natural nymph silhouette. He gave me several, and I tied more of my own to test on a favorite section of the Madison River near West Forks, where the pattern had never been used and where the standard Beadhead Pheasant Tail was in every angler’s arsenal. I doubled my take on a heavily fished run using it, and several other of André’s students reported similar increases. At times, as we say, the fish may have seen a particular pattern far too frequently.
Dave Hayashi owned the Grizzly Country Store at Lake Davis before the first pike infestation. He lamented to me that a fly order for damselflies came back from Africa with the wrong colors. Not wanting to accept the loss on 12 dozen gross of red, green, and tinsel bizarre, untraditional damselfly nymph patterns, he put them in his fly bins at a discount. Reports started coming in that an unrealistic imitation was the best fish producer that year, and he sold out. Just when you think that you have this angling game figured out, something like this surfaces. Are the fish outwitting us, is it happenstance, or are we outwitting ourselves?
I was reminded of a study on crow nesting behavior while I was taking fly-tying classes from André Puyans. One of my fellow students accidentally tore off a nymph leg after tying a nicely proportioned Callibaetis nymph. He wanted to throw his fly away, but Andre said, “Fish can’t count. I don’t think they know the difference between five or six legs.” However, it seems that crows, at least, can count, up to a point. In the study that I did at UCSB, I was trying to get some of these very intelligent birds to settle down so I could observe and record mating and nesting behavior patterns. Merely hiding and observing with binoculars from a distance didn’t work, and the crows remained agitated. My mentor professor suggested a blind. I built one out of palm fronds we had been using for a beach luau. The crows, kin to larger ravens, didn’t buy it, so I asked a friend to accompany me into the blind. We waited 10 minutes, and my friend left. The crows didn’t buy the idea that the blind now was empty, and they remained agitated. My professor suggested a third person in the blind and two out. Three of us went in, and 10 minutes later two out. (It cost me a six-pack.) This time, the birds bought it, and I was able to get hours of good observation and detailed notes. So it seems that some animals, at least, can count, bird-brained though they might be.
At minimum, it’s obvious that fish are aware — that is, conscious to some degree — that they react to stimuli in predictable and unpredictable ways, and that being vertebrates, they have complex and sensitive central nervous systems, which many agree are needed for the “processing” of information.
The NPR scientist used the term “sentient” a number of times in discussing fish behavior. Sentience doesn’t necessarily involve rationality. Wikipedia declares that “sentience is the capacity to feel, perceive, or experience subjectively. Eighteenth-century philosophers used the concept to distinguish the ability to think (‘reason’) from the ability to feel (‘sentience’).” Many equate sentience with consciousness, and “sentient being” crops up in Buddhist writings. Native Americans believe that all sentient creatures possess active spirits, some more powerful than others. Wikipedia also says that “fish intelligence is . . . the resultant of the process of acquiring, storing in memory, retrieving, combining, comparing and using in a new context information and conceptual skill.”
The biologist in me wants to believe that fish behavior is mostly just stimulus reaction, with little if any cognitive behavior, but the pieces don’t always fit, no matter how hard I try to make them. After 50 years or so on the water, I can’t help thinking that at times, fish behave in an intelligent way. The stripers at Del Valle “know” that the trout stocking truck shows up every Thursday around 11:00 A.M. Putah Creek browns prefer flies with a light green Baetis body color. So we fellow sentient beings stoke our campfires and ponder.
