Consider the black duck. From the beaver ponds of Maine to the bays and sounds of Long Island, the salt marshes of New Jersey, the secluded coves along Chesapeake Bay and the barrier islands of North Carolina, this dusky cousin of the mallard once reigned supreme. Its reputation as the wariest of fowl prompted the late Van Campen Heilner in 1939 to declare, “He’ll be around long after other species of ducks have disappeared.”

In addition to its inherent wariness that presumably protected it from gunners, the black duck’s future was believed further secured by an abundance of nesting habitat. Its northern boreal forest breeding grounds remained largely intact at a time when prairie-nesting ducks faced a hostile agriculture that drained myriads of northern-prairie potholes and plowed under vast expanses of native grasslands.

Yet, less than two decades after Heilner wrote his words, biologists began sounding alarms. Winter surveys revealed black ducks were declining in both the Atlantic and Mississippi flyways. This sparked a 40-year debate that continues to this day over the cause of the black duck’s downward population spiral, a debate that ultimately came down to one side blaming invasive, over-sexed mallards, while the other side cited overshooting.

The controversy virtually assured that waterfowl management would fail to act in a timely manner to restore the species to its former abundance. Only two significant management actions have been taken in the past forty-one years – the last in 1983. Now, new studies conclude the mallard is blameless. Overshooting is viewed as the primary cause of the black duck’s decline.

The black duck represents a classic case of waterfowl management procrastination. It is not unique to the black, for it is a common practice in the management of other species. It is a primary reason many once abundant species are declining.

Winter surveys chart the black duck’s decline from 1955-2000 in the Atlantic and Mississippi flyways, as shown by five-year averages in the following graph.

Figure 1. Winter surveys reveal black duck populations have fallen sharply in both the Atlantic and Mississippi flyways. Atlantic Flyway black ducks fell from a peak of 582,500 in 1955 to 206,428 in 2004, a decline of 65 percent. Mississippi Flyway blacks dropped from a high Source: USFWS.

As you can see, the black duck has fared poorly. The combined winter population of both flyways from 1955-04 reveals an overall decline of 70 percent, a sharp drop for a species whose breeding habitat is not under siege.

The plummeting population prompted the U.S. Fish and Wildlife Service in 1963 to take its first tepid step to nurture a recovery. It reduced the daily black duck bag limit from four to two. This failed to lower the kill. In fact, the opposite occurred. Harvest data reveals the Atlantic Flyway’s annual kill in the two years preceding the restrictive bag averaged 209,700. From 1963-82 the annual kill averaged 259,652, an increase of 19 percent.

How this unexpected result occurred is twofold. Harvest data from 1963-82 reveals the average Atlantic Flyway waterfowler hunted seven and one-half days each autumn and bagged “eight-tenths” of a black duck per season. This works out to about “one-tenth” of a black duck per hunt. The two-bird daily bag thus was nearly twenty times greater than a hunter was likely to “kill” each day in the blind. Secondly, the number of active duck hunters nearly doubled, increasing from an average of 176,650 in 1961-62 to 324,776 from 1963-82.

The service waited 20 years – twenty years! – before concluding its tepid, initial action was a failure and that something more must be done to halt the black duck’s continuing decline. In 1983 it reduced the bag limit to one per day and further decreed that each state must reduce its kill by 25 percent from its average 1977-81 harvest, a demand that forced some states to cut back the number of days blacks could be hunted. These states adopted an abbreviated “season-with-a-season” for blacks.

At the same time a few biologists looking at possible non-hunting causes for the black duck’s decline identified a new culprit -- the dreaded, over-sexed mallard. It was extending its range eastward. New studies suggested it was competitively superior, driving black ducks from traditional breeding haunts. Another alleged over-sexed mallard drakes wantonly seduced black duck hens, diluting the black’s genetic heritage.

Waterfowl management enthusiastically embraced the findings and began publicly blaming the mallard for the black duck’s plight. This proved a public relations triumph, for it absolved the service of responsibility for the failure of its new gunning restrictions to produce a recovery

Yet, blaming the mallard was disingenuous. Anyone familiar with the historical data could have immediately dismissed the mallard hypothesis as biologically delusional. For example, breeding-ground surveys found the mallard had extended its range eastward, suggesting a population increase. This is a false inference. The eastward expansion was limited to a few areas. Atlantic Flyway mallards were declining almost as fast as the black duck. Winter surveys in 1983 disclosed the Atlantic Flyway mallard population had fallen 50 percent below its 1950s peak, while blacks had declined 65 percent. Increasing numbers of mallards were not and are not invading and occupying the black duck’s entire range.

The over-sexed mallard idea also should have been immediately debunked. Harvest data did not at the time, and has not in the years since, revealed an increase in the number of mallard-black hybrids, as would be expected if hordes of invading drake mallards suddenly began preying on innocent, swooning black duck hens. (See: Black Ducks: Forty Years of Mismanagement , Nov. 5, 2002.)

And this was only the initial tip of the iceberg. Within a decade a few astute biologists began completing behavioral studies that further challenged the mallard hypothesis. They found drake mallards preferred to mate with female mallards – not black duck hens. Moreover, they found black duck hens preferred black duck drakes for a mate. These findings further contradicted the mallard hypothesis.

Biologists examined two additional hypotheses: (1) the mallard was competitively superior and displaced black ducks from choice breeding sites, and (2) the mallard also excluded other mallards, thus reducing a site’s potential for hosting a maximum number of breeders.

A 1998 study by Maine biologist Daniel G. McAuley found “mallards were displaced as a result of black duck aggression more frequently than were black ducks.” Additionally, McAuley found single mallard pairs “do not necessarily exclude other ducks from an entire wetland.” Indeed, his latest 2004 study found most of the time more than two pairs of “black ducks or mallards or both used the same wetland,” and this was true for more than half the wetlands observed.

“Even if wetland habitat were limited,” McAuley concluded, “black ducks and mallards could use the same wetlands.”

McAuley also examined the additional hypothesis that mallards out competed black ducks for scarce foods, diminishing the black duck’s reproductive potential. He found no shortage of food in Maine, and cited a study by Madduck’s Norman Seymour that “there is no published evidence that black duck reproductive success in Atlantic Canada is limited by the quantity and quality of spring or summer food.”

“Because breeding habitat and food are not and have not been limiting within the range of the black duck,” McAuley concluded, “competitive exclusion and reduced ‘breeding propensity’ are not plausible causes of the black duck decline.”

McAuley then examined the use of aerial breeding-ground surveys. He found the surveys do not adequately document the duck population of a wetland either by numbers of ducks or by species. McAuley concluded the use of aerial surveys to prove a cause-and-effect relationship, as was the case with some blame-the-mallard studies, represented “an inappropriate use of these data.”

What, then, caused the black duck’s decline?

“Recent evidence indicates that black duck hunting mortality was additive in the 1950s, 1960s and 1970s,” McAuley said, noting that “recent surveys of breeding pairs depict increasing numbers of black ducks across most of the range. These increases are occurring while numbers of hunters and black duck harvest are declining in Canada.”

McAuley suggested future “research efforts should focus on causes of black duck mortality, especially hunting mortality.”

The black duck’s beleaguered population status today thus represents a classic and all too common example of waterfowl management procrastination, a willingness to grasp any biological idea, however preposterous, to postpone or delay taking action necessary to maintain or rebuild our waterfowl flocks.

The latest biological studies suggest the black duck’s recovery should be a managerial slam-dunk, especially with an abundance of undisturbed and unoccupied breeding habitat that could host far greater numbers of nesting blacks. The sport kill is the one aspect of black duck mortality the service can easily control.

Will the U.S. Fish and Wildlife Service heed the new findings? Has it procrastinated for so many years that nothing short of a hunting moratorium will allow the species to quickly recover? Why have our waterfowl conservation organizations failed to demand the restoration of the species?

These questions are critical. The service’s current claim that it has “stabilized” the black duck’s decline is a self-serving rationalization. The species remains below its desired population goal. The historical record tells us the black duck’s bleak fate for the past half century was sealed by management’s failure to act swiftly and boldly at a time when the decline easily could have been reversed. Will the service now act quickly and decisively to reverse the decline? Will it continue to dither and do nothing?

Only time will tell.