I got copied on an exchange of e-mails recently between scientists attempting to reconcile the perceived reality in the marsh of the last several seasons with the compensatory kill hypothesis. Interesting stuff, particularly as it illuminated for me the thinking of the Grand Ayatollah on that subject – he who preaches the irrefutable compensatory dogma to all the true believers. An ethical point is in order before I examine some of the more specific insights spawned by the wisdom emanating from such a lofty pinnacle.

The compensatory kill hypothesis teaches that hunter take has no impact on waterfowl populations – that the birds killed by hunters would die of other causes before returning to the nesting ground, if hunters did not kill them. The hypothesis absolves the hunting fraternity of all responsibility for the welfare of the flight. If we kill, it does no harm. If we refrain, it does no good. Thus, we are invited to indulge without consequence, like the alcoholic who believes that he can handle two double vodkas without falling off the wagon, or the overweight guy convinced that he can eat the whole chocolate cake without setting his diet back a notch.

I cannot imagine a more pernicious mindset, a more misguided excuse for long seasons and high bag limits not justified by our populations and experience in the marsh. And that’s hardly the worst of it. What more does the scofflaw need to excuse outrageous over gunning? The more numerous hunters who abide by the law reluctantly – whose kill glands tussle continuously with conscience – can now take that extra bird or two or three with a light heart. Or shoot a double limit to compensate for the hunting day missed last week. Because it doesn’t matter, right? The limit has no meaning, no practical utility. It’s just another oppressive bureaucratic infringement upon personal liberty.

I encourage the compensatory kill theorists to speak out with clarity and courage in support of their convictions. For if they did, they would advocate for abolition of all closed seasons, bag limits, restrictions on methods of take, the prohibition of night shooting, etc. And thus they would discredit themselves, liberating the rest of us for more uplifting tasks. I don’t expect it to happen. And in the meantime, hunters are taught that they have no stewardship responsibility, a message well calculated to reverse a lot of the good work that has been done over the last several decades.

That is far from the worst of it. Let’s go back to the e-mails, where I learned from The Source that compensatory kill has a corollary. The corollary goes something like this. Good production during a particular spring does not translate into an increase in breeding pair counts for the nesting season that follows, all other factors being equal. Why? Because enough birds will die somewhere along the migration circuit so that “recruitment” (i.e., the addition of the new birds) will be cancelled out and populations will not increase. As hunter kill cannot be the culprit (see main theory), environmental and natural forces must do the killing, at a rate sufficient to offset substantially all of the production.

Think about that for a moment. Increased production does us no long term good because so many of the birds die before they can breed. Thus, management of the breeding grounds for good production serves one purpose and one purpose only – to create more targets for the gun the following fall. But not to worry – because any increased kill from that quarter will not affect populations. (I am not making this stuff up. You can find it on the Internet yourself if you have time and “no life” as the teenagers would say).

The guys who advocate these theories (and brook no contrary views of any kind whatsoever) hold high places in the establishment of waterfowl management. They have substantial influence with the regulators. They did not get drafted for those roles. To the contrary, they pushed their way into them – and on that ground should be held accountable for answers to at least the following questions.

Question 1: If so many birds die of natural causes every year (and remember that we’re talking millions here), where do they go to die? In most parts of the country, a large proportion of wintering habitat is located on managed wetlands. Why is it that the managers of those wetlands don’t regularly report windrows of the dead and dying, stacked up like the casualties at the Battle of the Somme? Aside from the occasional outbreak of botulism in the late summer and waterfowl cholera during the winter, reports of large-scale die offs are quite rare.

The phenomenon should be most often observed during restrictive years when the hunting season is short, limits low, pressure relatively light. For that’s when all those birds we would be killing (if the regulators would only “let us have at ‘em, ‘cuz ducks are for killin’”) should be dying under the onslaught of nature’s artillery, leaving their earthly remains floating on the ponds of winter to vindicate the Grand Ayatollah and his acolytes. Hasn’t happened, certainly not as a regular, annual occurrence, certainly not in the millions of birds.

In fairness, some carnage may take place out of sight. From radio telemetry studies, we know that a substantial segment of our west coast pintail migrate over the open Pacific between the Klamath Basin and the Yukon/Kuskokwim Delta. Tens of thousands could die on that hazardous journey and no one would be the wiser. But where on the Mississippi or Central Flyways could you hide a half a million or so dead ducks, their corpses decaying unseen, unsmelled and unremarked? An event like that would never pass unobserved on the Washington/Oregon/California segment of the Pacific Flyway, of that I am sure. The places where our birds congregate on their migration receive too much regular and close attention for such a thing to occur.

Conditions vary from year to year, of course. Drought on the wintering ground can stress the birds. In mature condition at that time of year, and not tied to a nest or a dependent brood, they can move and thus protect themselves to a certain extent. They are very hardy creatures after all. And on most flyways, we have far more acres of good, virtually drought proof wintering habitat than birds to use it, which adds to the safety factor. That is certainly true in our Central Valley where hundreds of thousands of acres are flood irrigated every fall and winter to dispose of rice straw through decomposition. It is a rare occurrence here and in these times to take a bird toward the end of the season that is in bad condition. To the contrary, most are fat as footballs, in great shape and primed for migration.

So I suggest that the next time you hear about all those hypothetical deaths, make a simple demand: “Show me the bodies.”

Question 2: If hunter kill doesn’t count (whether high, low or in between) and the product of a given nesting season doesn’t translate into breeding pairs the following spring, how is it possible for populations ever to increase? Yet we know that they do – and usually in direct proportion to improved nesting conditions – strongly suggesting that increased production does translate into more breeders the following year. Moreover, we know that populations tend to increase in multi-year cycles, as during the period 1995-2000. Multi-year increases give the lie to any idea that each increase is just a random event, a happy but fortuitous blip on the graph of relentless mortality.

Question 3: If hunter kill doesn’t impact populations, how do you correlate the decline in hunting in recent years on the Mississippi Flyway with the increased kill over the immediately preceding period? According to the information contained in the Arkansas Wildlife Federation report, the total kill in those states greatly exceeded the winter count, except in Louisiana. The total kill on the Flyway as a whole exceeded the winter counts by close to a million birds (on annual average during the period ’96-’00). The kill doubled over the kill for the preceding five-year period, while the winter counts increased only slightly – meaning that a larger percentage of the total flight fell to the gun. Strong production sustained this kill rate for a few years, just long enough for hunters and commercial interests to get hooked on it. Then production fell and hunting declined, although kill numbers held relatively high due to the liberal framework and the increase in “hunter days.”

The compensatory kill crowd would have you believe that the 7,657,400 (ponder that number for a moment, let it roll around in your head) birds killed per year on that Flyway during the ’96-’00 period would have died anyway, without hunting – that the dramatic increase in kill had no impact on the winter counts. Nor has it had any part in sweeping the skies clean of ducks over the southern segment of that Flyway during the recent seasons.

I submit that those numbers suggest a more obvious and likely scenario. We produced a lot of birds during the ’96-’00 period that flew the Mississippi Flyway – and hunters killed more than half of them. Had hunters killed fewer, some of the survivors would have died of natural causes but a substantial number would have returned to the nesting grounds where the usual percentage would have brought off broods, assuming the existence of available nesting habitat. Had production thereby increased, the added increment would have elevated the chances that more birds would return to the nesting grounds the following spring, some of them would have produced broods and the skies might not have been quite as empty the following fall. Just a theory of mine, you understand.

And my corollary to counter that of the Grand Ayatollah is that when your kill rises to equal or exceed your post-season winter counts, you are killing half or more of your birds, which is probably not conducive to the long-term health of the flight.

The whole business comes down to a simple proposition. When you shoot a duck, you know it will not reproduce. If you miss and the duck survives, it might participate in producing a brood. Live ducks might survive long enough to breed; in short, a possibility. Dead ducks won’t; in short, a certainty. If we care about the health of the flight, should we not place possibility over certainty, at least to some limited extent?

Darwin taught us that not all offspring of any species survive. The rate of survival varies with the conditions they encounter. In a changing state of nature, the more robust and resourceful endure to reproduce, and the less so do not. When times are relatively benign, survival rates rise as the weaker can deal with the conditions. When times become more severe, however, survival rates decline and only the stronger tend to make it.

Place these accepted concepts against the variable, difficult to predict and hazardous conditions that waterfowl must overcome to complete even a single migration cycle, and certain propositions emerge.

When a population is high and rising, and most of the available nesting ground is being used by breeders, hunter kill probably does not significantly reduce the number of birds that will return to the nesting ground and successfully reproduce the following spring. At some point on a declining cycle, however, the reverse becomes true. We cannot fix where that point occurs because it is powerfully influenced by the state of the nesting grounds – which varies from year to year, based in large part on precipitation.

Prior to the migration cycle, we also cannot know what special calamities might await the flight due to weather or disease. Thus, hunter kill will likely become “additive” if we pile it on top of serious cholera outbreaks or shortages of feed on the wintering ground. And in these regards, what is true for one flyway may not apply to another. Worse, this guessing game varies from species to species. Conditions that impact one may have a lesser or greater impact on others. For each species has different habitat needs and migration patterns.

The compensatory kill theorists have never attempted a fine-grained analysis of this sort, species by species, cycle by cycle. From what I understand, they admit that the information would be most helpful – but that it could never be gathered “scientifically.” Too many variables. No way to create a “base” case. So we make a blanket assumption that cannot be accurate, admitting that a true scientific matrix cannot even be designed for practical implementation, let alone subjected to proof. And then we use that blanket assumption to drive policy. I cannot imagine any other field that calls itself “science” where such a thing would be seriously considered for a moment, let alone accepted.

If, (1) the quality and quantity of nesting habitat constitutes a critical and variable link in the production chain, (2) nesting habitat produces no birds unless breeding pairs arrive in the spring to use it, and (3) we seek through our management to stabilize, sustain and grow our populations, then we must accept some hard realities. In August, when the kill regulations are set, no one can be sure as to the extent and quality of the breeding habitat that will be available the following spring, or the number of breeding pairs required to make optimum use of that habitat.

But we could make some reasonable projections -- at least as reasonable as those produced by the “adaptive harvest management” methodology, insidiously prejudiced by compensatory kill dogma. To do so would require focusing on a goal that currently receives nothing but lip service, if that. Official efforts to adjust the regulations to assure return of an optimum number of breeding pairs to the nesting grounds, based on projections of likely precipitation, etc., are as rare as sober sightings of an Albino Sasquatch.

Darwin never suggested that all offspring would inevitably die before they can reproduce, that mortality precludes increase in the numbers of a species. To interpret him in that fashion simply justifies the killer mentality that has degraded our sport. I challenge the compensatory kill theorists to show us the bodies. A statistical exercise will not cut it, particularly as our numbers are fuzzy and susceptible to manipulation. We are long past the time when we can afford the luxury of having a fictional specter of phantom dead dictate critical management policy, serving only as a justification for excessive killing.

One wonders if the purveyors of the compensatory kill theory are hunters, afflicted with uncontrolled trigger itch, in addition to being men of scientists. That would at least suggest an explanation for why we are where we are.