Measuring seems to be an ingrained trait of anglers. Perhaps we are not always quantitative, as in "I hooked a bunch of risers on that spinner fall," or accurate, as in "You should have seen that eighteen-incher I landed" (actually fourteen inches). But the need to measure is always there. Back in the grayling days, the catch was often measured by the height of the dead fish pile on the bank: waist high, shoulder high, etc.
The quality of fishing is now measured in numbers and size, as in Eric Sharp's article in the April Riverwatch. This is important because we all prefer to catch as many large fish as possible. Furthermore, the trend is certainly not encouraging: the fish population in catchable sizes in the Au Sable system has declined by nearly an order of magnitude during the last thirty odd years, a cause for serious concern.
However, I was shocked to learn there is apparently a movement to solve the problem by using hatchery trout. Where did this aberration come from? I always thought Au Sable advocates would always buck the hatchery system.
Although Sharp presents a balanced summary of the issues, one of his concluding points is that naturally-managed solutions to the problem may be unacceptably long for those, say, sixty-five years of age or older. To which, I must ask: For whom are we actually managing this ecosystem? Are we managing it for our children's children, or are we content to pay lip service to a deeper understanding of the waters so long as the measurement of the catch is up to expectations?
In the end, a proper resolution of the situation requires two things: a clear, concise description of the problem, and the development of proper measurements for the changes resulting from our actions - a metrology of our river.
The first requirement may be the big stumbling block, and therein lies my greatest fear. Complicated concepts usually lead to frustration. In turn, frustration leads to rash decision making based on perception, and not on data. Most people may be surprised that the majority of human decisions are based on perception rather than on confirmed data, the only measurement being the outcome. Most large American corporations fall prey to this temptation. Arguments then begin and in the end the individual with the largest stick wins. The best advice I ever received from a senior scientist where I work was to collect data. Nobody can argue with data.
Do we really have a clear statement of the problem? To those who think the problem statement is simply, "We must have lots of big trout now," I suggest they stop off at one of the trout farms and haul in a pile. To be more reasonable, most anglers probably want a healthy population of fish in a healthy river, where they've got some hope of catching a few. Hatchery fish will not bring about either feature.
The reasons behind declines in trout populations are merely hypotheses. Hypotheses are only useful if they are tested. Since many are possible the testing process must be applied to a few of the more reasonable based on existing data. Otherwise, the empirical evaluations are too extensive (read expensive) and time consuming. For example, the hypothesis that the river has become "too clean" is about to be tested by fertilizing the river with leaves. While this idea is interesting, do we have data on nutrient levels in the river for the last thirty years? If so, there should be a correlation between the nutrient level and the fish population. Simple. If there are no such data then the idea is merely an hypothesis. I would be amazed if the river was too clean. Remember, grayling catches were measured by pile heights back when the river was "too clean."
And some more data: over the last twenty years, the numbers of Trico spinners in my favorite stretch of the North Branch have decreased from forming a mat on the entire surface of the stream to a bare trickle down the primary current flow. During this time, the density of aquatic vegetation in the same stretch has remained nearly constant. What does this say?
How about a different problem statement, such as : "We don't have the data to properly assess the Au Sable water quality." Although this problem statement doesn't directly address the bigger trout issue, it may be the simplest and most basic assessment. While the issue of nutrient loading is important, it may not go far enough.
I don't know if all the necessary data exists and merely needs to be analyzed. I suspect the need is some combination of data from previous work and further data generation.
For example, what fraction of cabin owners along the river know that using ethylene glycol to protect the plumbing in the winter may be toxic to aquatic life while propylene glycol is more readily tolerated? Do we have data on concentrations of ethylene glycol in the water over the last thirty years?
Another point. North Down River Road has now become the main trucking artery for travel between Alpena and points west of Grayling. To maintain this traffic during winter enormous quantities of salt brine are used. As the salt dissolves it enters the river through the amazing conductivity of the Au Sable hydraulic system. Although sand is effective at filtering particles, it is not a de-ionizing medium. Do we have data on dissolved salt levels in the river over the last thirty years?
It is important to know that chemically active impurities can be biologically important at parts per billion (ppb) and even at parts per trillion (ppt) level. Are there data on levels of impurities caused by human activity over the last thirty years?
Another hypothesis is contamination of ground water with toxic impurities, such as heavy metals, by the military. Perhaps. But unless we have data, it's all just an argument. And the one with the biggest stick wins. Any guesses about who's got the bigger stick? Is it the military or is it the coalition of The Anglers and AMAC? Moreover, do we know the threshold toxic limits of the trout's food chain? I certainly believe insect populations have shown signs of stress.
We will not be able to afford to analyze the entire ecosystem. That shouldn't stop us from laying a solid foundation for understanding based on real data. We must try to avoid decisions based on perception. Let's start by figuring out what we do have in the way of historical data through a literature search. Of equal importance would be to start collecting and analyzing water samples on some kind of regular schedule. Another would be a study of the trout's entire food chain and the sensitivities of the constituent organisms to contaminants. These are not trivial, inexpensive projects. They will not be accomplished overnight.
Let's do this the right way to produce a healthy river with healthy fish - and make sure we measure up in the eyes of our children's children.RWOL
© Copyright 1997 - , Anglers of the Au Sable, Inc. All rights reserved. Last modified: June 18, 2002
