Record keeping & Fishing Success

Figuring It Out

Tony Entwistle talks about the relationship between record keeping (statistics) and angling success.

“The memory of an old angler is rich with innumerable spoils and trophies of the past; it is vivid, detailed, exact. Something in the nature of the sport makes our angling memories more enduring than others… Every observation he has ever made in fishing, however minute, has contributed something to his present skill, so that he seems to know by instinct, at the first glance over a pool, where the trout will lie, how they are to be approached, and in what order. Every mistake he has ever made now warns him, and every success guides hand and foot and eye as he works his way along strange water. He has acquired what might be called a bodily wisdom, which is really a host of dormant memories and the deduction, often unconscious, that he has made from them…A good angler may forget freely and profusely about every other matter; he remembers everything about angling.” Odell Shepard, Thy Rod and Thy Creel (1930).

It is a tired cliché that “a good day’s fishing isn’t dependent upon the number of fish landed”. But talk to any angler and inevitably the most vivid and enduring memories are based around the fish they have caught. Maybe angling memories and angling success are not entirely exclusive?

Memory is, however, a fragile quality and anglers’ memories are famous for being more fragile than most. There are good reasons why non-angling associates joke about ‘fishermen’s lies’, but memories backed by some sort of record have substantially more validity. Since the earliest times, there have been anglers who have recognised the value of giving permanency to their memories by way of carved fish, paintings, mounted fish, angling diaries, photographs, and…statistics.

David James Duncan in his classic flyfishing novel, The River Why (1983), points to anglers’ passion for statistics, writing: “Like gamblers, baseball fans, and television networks, fishermen are enamored of statistics. The adoration of statistics is a trait deeply embedded in their nature…Statistics are a tool upon which anglers rely so heavily that a fish story lacking numbers is just that: a Fish Story. A fish without an exact weight and length is a non-entity, whereas the sixteen-incher or the twelve pounder leaps out at the imagination, splashing the brain with cold spray. The strange implication is that numbers are more tangible than flesh…”

Connecting observations, conclusions, and practical application is the tortuous route every angler must take. Successful anglers are simply those who make the most accurate observations and draw the most valid conclusions.
I wasn’t long into my angling ‘career’ when I began collecting the first statistics. Once over the obstacle of actually catching a fish, keeping a record of what I had caught was natural evolution. In those days, we whacked any fish over legal length and my early statistics were a crude record of ‘how well I had done’, based on preserving what seemed important at the time -- the date, the number, and the length of trout landed, because they were all mostly small and anything over 15 inches was regarded as a ‘big one’!

As my angling interest evolved from bait, onto spinners and eventually to flies, the sophistication of my statistics developed too. The positive connection between past successes as the foundation for recreating future success was plainly evident, even to a schoolboy. By my late teens, the routine of collecting data from fishing expeditions was well established. My database now included specifics of location and catch-method. The passage into flyfishing also spawned the inevitable curiosity as to what trout ate, and gut analysis soon became standard procedure. Instead of heaving the guts into the bushes, stomach contents were washed and spread out on newspaper to look over the various ‘bugs’ on which the victim had been feeding. These early gut analyses weren’t particularly detailed, but I learned the difference between mayflies and caddis and quickly came to recognise the seasonal importance of various insects, such as brown beetles to evening flyfishing, on many of our local South Canterbury streams.

Unfortunately, those very first schoolboy records have been lost and I regret not fully appreciating their value as a snapshot of the local fishing around Geraldine in the late 1960s and early 70s. It is left to my memory to ‘document’ the decline of what were once varied and productive small brown trout fisheries. John Gierach, in Sex, Death and Fly-Fishing (1990) once wrote: “I don’t know exactly what flyfishing teaches us, but I think it is something we need to know?”

My record keeping has not always been continuous, but has occurred in a series of fits and starts. During the mid to late 70s, I worked my summers on Lilybank Station, at the head of Lake Tekapo, where hunting guide Gary Joll had started a series of outdoor camps for youngsters. I became the trout fishing instructor and, to help build an overview of an unfamiliar fishery, I recommenced gathering and recording fishing data.

These efforts were more sophisticated and I even had special record sheets printed. I made more accurate notations of invertebrate contents and also my first identifications of fish sex. On occasions I even collected scale samples and undertook some basic aging of the fish. A feature of these records is the calculation of fish Condition Factors (derived from the formula CF = 100,000 times weight divided by length cubed). Condition Factors were a prevalent statistic in many fishery reports at that time and, although not referred to as often nowadays, the CF is a useful indicator for comparing the condition of fish within or between populations and can provide a useful historical snapshot of the relative health of fisheries.

The data from this time remains a fascinating insight into a fishery few anglers knew much about at that time. I remember the local Acclimatisation Society ranger expressing doubt that we were accurately identifying what species of trout we were catching. As far as they were aware then, there weren’t any rainbow trout in the upper Lake Tekapo system. Our photos and the data were positive proof they were wrong.

In 1978, I moved to St. Arnaud to become an outdoor education teacher and began my love affair with the wonderful fisheries of the Nelson district. Some of the fieldwork involved invertebrate sampling in the Buller River, which gave me a fantastic opportunity to study trout food more closely. The magic of a 3D microscope precipitated the first real connection between insects observed on the river and the trout flies I subsequently created at the vice. The legacy has been the ideas for many of my most successful trout flies.

I maintained these records for five years and then, as I left teaching and started my guiding career, I stopped recording again for a few years. As much as anything, this may have been because catch and release had become an important factor in my angling and I had yet to develop any on-river routine for collecting vital statistics. There were no weigh nets, so only the largest fish were weighed and there was no longer a convenient quota of ‘bodies’ available to be measured at day’s end. Significantly, I have never recorded detailed gut analyses again, beyond casual observation from an occasional trout taken for the table.

A new period of data collection got underway in 1984 when Howard West (then president of Scientific Anglers 3M) encouraged me to recommence recording data from my guided fishing as the basis for an annual newsletter to guided anglers. The Nelson region in the early 80s was not well known internationally as a trout fishery and the newsletter proved a great way of getting the message out to potential visitors about the excellent fishing opportunities around the top of the South Island. Records now had a practical use beyond a simple fishing history and my statistics became a valuable marketing tool.

By this time, I had gathered a team of guides together to help with the growing workload, which presented a great opportunity to grab huge amounts of data that could help build a detailed overview of the local fishery. Instead of recording a few simple fish measurements and qualifying them with a series of subjective comments, we produced a daily data sheet to help standardise our observations. Not only did we gather statistics on the fish caught, but also the numbers of trout sighted and the number of takes. These statistics are useful in helping document visible changes to fishing opportunity, especially fishing to sighted fish. Rather than relying purely on ‘fish landed’ as a measure of daily success, recording ‘fish takes’ is a way of overcoming inconsistencies in the relative skill level between guided anglers. From the perspective of ‘available fishing opportunity’, 15 trout sighted, 10 fished, six takes and one fish landed tells a completely different story to three trout sighted, three hooked, and three landed.

In addition to standard stats, such as fishing method and the identity of insect hatches, we also attempted to quantify the physical factors that influenced a fishing day, assessing river conditions (flow, water clarity, water temperature) and weather conditions (air temperature, cloud cover, rain, wind direction and strength), to help to build a picture of the physical variations within and between successive fishing seasons.

Ultimately, there was also a purer use for many of these records, beyond the marketing value of our annual newsletter. They formed the basis of a submission on the importance of recreational and tourist fishing in the Buller River catchment, which proved helpful in eventually securing the Buller Water Conservation Order, and guiding friend Zane Mirfin used them as part of his Master’s thesis, entitled Trout Fishing In Nelson -- Management of a Recreational Resource.

While my records were becoming more detailed, they still involved quite a lot of subjective content, which was hard to convert into useful statistics. Their value, however, as a record of angling effort was undoubted. Even in its simplest form, the data highlighted a remarkable consistency in fishing results between seasons, despite large variations among individual months. Overall, the figures also showed that our guiding at that stage had not had any visibly negative impacts on the physical qualities of the fishery, despite the worries of fishery managers.

By 1990, fisheries management were starting to become concerned about more esoteric fishery qualities, such as ‘angler satisfaction’. In July 1996, in response to growing concerns from Fish & Game New Zealand and the NZ Professional Fishing Guides Association about the perceived changes in some of New Zealand’s popular backcountry fisheries, the Foundation for Research, Science and Technology (FRST), funded a team lead by Dr John Hayes of Nelson’s Cawthron Institute to research the impacts of increasing angling use on these special fisheries. Hayes’ team looked specifically at two issues -- the social impact of increasing numbers of tourist and New Zealand anglers on angling satisfaction, and the impact of angling on trout stocks, (the results of which have featured in previous issues of Fish & Game magazine).

I was lucky enough to work alongside John’s team as one of the anglers engaged in their ‘catchability studies’ and in the process learned a lot more about the collection and value of ‘measurable’ data. My record keeping had fallen by the wayside for almost 10 years and, like Howard West had done 15 years earlier, John encouraged me to start collecting data again. He had a great line: “Science is simply the quantification of the obvious…but first you have to see it!” John thought it was a waste that, as a guide observing angling on a very regular basis over a wide range of fisheries, I didn’t at least measure and document what was going on around me. This time, however, he showed me how to take greater care to record observations in an accurate and quantitative way that would allow for more critical statistical analysis.
One of the great revelations to me during the Cawthron work was the significant role water temperature played in influencing every day’s fishing. Although I knew that water temperature was a factor influencing angling success, I hadn’t understood its real significance because I had never measured it in an accurate way. I never realized, for instance, that water temperature could increase by 6C or more during the day, as it moves to match the surrounding air temperature.
Since then, my data has revealed that when fishing for brown trout, the best fish-catching days are invariably those where the water temperature moves through more than 2C during the fishing period (but a move of 2C doesn’t necessarily mean that there will always be good catches), and that good fish-catching stops when the temperature change stops (but will often resume again when it drops, as often happens late in the day during spring and autumn). It is also evident that the worst fish-catching days occur when the water temperature doesn’t move through a minimum of 2C (and I have never recorded a good day under these circumstances). It seems that some trigger point related to water temperature change, rather than a specific temperature level, is one of the key critical factors influencing fishing success.

Analysing parameters like water temperature won’t ‘catch you more fish’ per se, but understanding any variations certainly helps govern an angler’s expectations and allows him to plan and focus angling effort more effectively. For example, morning water temperatures in spring and late autumn are typically cold and it takes time for them to move. Fishing at these times, then, is frequently slow or unproductive. So rather than starting early, anglers who understand the temperature regime of the river they intend to fish can save their energy until water temperatures start to move. The chart measuring the percentage of trout caught at specific water temperatures, clearly illustrates the prime average temperatures affecting catchability. However, while these average temperatures are a useful working guide, the optimum temperature regime for individual rivers can vary quite markedly from this average and the angler, who keeps records complete enough to recognise these variations, has a powerful tool around which to plan his fishing.

For the moment, I collect data under the following broad headings: Location Data (where and when), Fishing Data (sightings, takes, water temperatures, and hours fished), Angler Data (whose fishing and how many other anglers do we meet), Environmental Data (river flow, water clarity, weather conditions, spotting conditions, visible hatches), and Catch Data (fish species, sex, length, weight, time, temperature, and successful fly). My tools are simple and include a weigh net, tape measure, and an accurate electronic thermometer. Observations are recorded in notebook in a form of shorthand that has evolved over the years, and are made at set periods during the day and whenever a trout is landed. Modern anglers have the benefit of computer technology to help record and analyse their observations and the rapid processing of large amounts of detailed data has never been easier, or more efficient.

Like many other anglers, my records and statistics are now an integral part of my angling and provide a fascinating document of where I have been, what I have seen, and why I will continue to find plenty of things of interest in angling, way beyond the fundamental task of catching a fish. They are at once a part of my memories and my fishing future and I would encourage more anglers to record their observations, but to do so accurately and without regard to inflating their ego. Only the angler knows ‘who is kidding whom’. But if I have learned one thing from my statistics, it is that the law of averages eventually prevails.

Wherever anglers get together to discuss their sport, the most common questions almost always seem to start with ‘Why?’ For instance: Why didn’t I catch that fish? or Why aren’t there any trout feeding in this run? I have few accurate answers for those angling ‘why’ questions and have learned to leave most of them to the scientists to try and answer.
Hayes commented to me once that in his experience: “Anglers invariably make accurate and valuable observations of what is happening around them, but then stuff it up by attributing completely erroneous conclusions!” The further I have progressed in analysing the data related to my own fishing activities, it seems the more relevant questions for anglers should be ‘what’ and ‘how’? For example: What factors influence trout feeding in this run? or How do they apply to successfully fishing it?

Recently, a guide friend called in with a young client who thought that their recent fishing hadn’t been so good. The client bemoaned the fact he had missed out on the ‘good old days’ and was curious to know what the fishing had been like 20 years ago. Rather than regale him with only the best memories, we pulled out the angling records from the mid-1980s and started comparing notes. Sure there were some fabulous days, especially when we started to access backcountry fisheries with helicopters. But there had been equally good days during recent seasons that matched those experiences. The old records also showed plenty of one and two fish days and more than a few ‘dreaded’ blanks, which memory might have chosen to overlook. Key indicators, like numbers of trout spotted per day, the average daily catch rate, and the average size of fish were all similar to recent seasons. The differences the records did pinpoint, however, were the rivers in remote areas we no longer fished regularly because helicopter access was now excluded, some small local streams that we no longer fished because they had been devastated by floods or other physical changes, and a visible reduction in the size of successful trout flies. Clearly, angling opportunities in some areas had changed and trout in other waters had possibly become a little more selective. But angling memories are more than just a collection of cold hard facts.

I would hate to think that anyone would be silly enough to think that angling-related statistics will somehow lead them to ultimately discover the ‘secret of fishing’. They would have seriously missed the point. Like David James Duncan said, again in the River Why: “I was afflicted with as pernicious a case of the numerical lease on life as any I’ve encountered, but I had the good fortune to discover that the essential pleasures of fishing are…independent of statistics…there are times and places to employ statistics and times and places not to…”

It’s a fine line that all anglers tread. In reflecting upon what it is that draws anglers to fish, it is perhaps pertinent to give the final word again to Odell Shepard:

“…One of these is the element of uncertainty always present in the sport of angling so long as it remains a sport…I have talked with fishermen, and have read the writings of others, who feel that they have quite eliminated the element of chance from their fishing. Weather conditions, height of water, season of year, popularity of streams, whims and caprices and conflicting engagements of trout themselves, make no difference to these gentry: they lay their calculations, adjust themselves to circumstances and always catch fish -- presumably all they want. My own attitude toward these anglers…is respectful but quite unmixed with envy…To my way of thinking there is something even vulgar in such self-confidence…The man who is absolutely certain he can catch trout under any and all conditions has no longer any good reason that I can see for doing so. He has ceased to be a sportsman and has decayed into a mere professional fish-catcher.”

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