For decades biologists have told us the adult hen is the most valuable component of the mallard breeding population. The adult female is most likely to hatch a clutch of eggs and fledge a brood, unlike a juvenile hen whose first nesting attempt often fails. An adult female also is more likely to re-nest if her initial nesting is lost, unlike a juvenile hen whose reproductive drive is weak.

The adult hen’s strong reproductive effort, coupled with successive springs on the nesting grounds, is key to her success – and to the success or failure of waterfowl management, for these highly successful breeding hens are believed to produce most of the young birds that swell the fall flight and determine whether each autumn we see few or many ducks.

Biologists believe hens learn from experience. Nesting failures prompt a hen to nest or re-nest elsewhere, a process that eventually allows her to learn where to build a nest that will not be discovered by an egg-eating predator or inundated by floodwater.

Why, then, does waterfowl management fail to protect adult hens? Instead of affording greater protection to adult breeders, an examination of harvest data shows that our current regulations introduce a bias that causes an increased kill of these valuable birds.

This bias should give each of us cause for concern, for it involves not only the total adult hen kill, but the increased percentage of adult hens in today’s bag.

Our first analysis compares the average annual total hen mallard harvest for the years 1994-1996 and 1997-2000. The latter period represents the years of “ultra” liberal regulations – longer seasons, larger bag limits, earlier opening dates, later closing dates and the widespread use beginning in 1999 of deadly spinning-wing decoys.

It is important to note that harvest data after the year 2000 is not comparable because of changes in the way the data is collected. (The earlier years involved the old “post office” survey. The post-2000 years are based on the “Harvest Information Program.”)

Figure 1. The average annual U.S. mallard hen harvest increased from 1.1 million in 1994-96 to 1.7 million in 1997-2000. Source: USFWS

As you can see, the data tells us the average annual hen mallard kill increased 53 percent. This might not be cause for great concern if juveniles accounted for most of the increased kill. But this is not the case, as shown in the following graph.

Figure 2. The average annual U.S. kill of adult mallard hens jumped from 410,000 in 1994-96 to 705,000 in 1997-2000. Source: USFWS.

This tells us the average annual kill of adult mallard hens increased 72 percent. More importantly, adult hens accounted for 36 percent of the total hen bag in 1994-96, but 41 percent of the bag from 1997-2000. Thus, we find that hens encountered a double whammy. Not only did the overall kill increase, but the percentage of adult hens in the bag increased.

As you might expect, the rate of increase in the mallard hen kill did not fall equally on the four flyways. The following graph shows the average annual mallard hen kill for each flyway for the years 1994-1996 and 1997-2000.

Figure 3. Harvest data shows the average annual mallard hen kill increased in each flyway for the years 1994-1996 and 1997-2000. The average total hen kill in the Atlantic Flyway increased from 129,000 to 162,000; Mississippi Flyway, 594,000 to 931,000; Central Flyway, 142,000 to 240,000; Pacific Flyway, 267,000 to 379,000. Source: USFWS.

As you can see, the average annual hen kill in the Atlantic Flyway increased 25 percent; Mississippi Flyway, 57 percent; Central Flyway, 69 percent, and Pacific Flyway, 42 percent.

The adult hen kill is a different story.

Figure 4. The average annual adult hen kill for the periods 1994-1996 and 1997-2000 increased in the Atlantic Flyway from 46,000 to 64,000; Mississippi Flyway, 213,000 to 383,000; 57,000 to 114,000; Pacific Flyway, 92,000 to 135,000. Source: USFWS.

As the above graph shows, the adult hen kill increased significantly in each flyway. In the Atlantic Flyway the kill increased by 40 percent, in the Mississippi Flyway by 80 percent, in the Central Flyway by 99 percent and in the Pacific Flyway by 46 percent.

Thus, harvest data reveals the increased hen kill, prompted by the liberalization of waterfowl hunting regulations beginning in 1997, fell most heavily on the older hens – the most valuable component of the mallard breeding population.

As if to underscore biologists’ findings that adults hens are the most productive breeders, we also find a drop in juvenile productivity over similar time periods as measured by age-ratios, the number of juveniles per adult in the bag of hunters. The average female age-ratio for the years 1994-1996 was 1.80. This fell to 1.59 for the years 1997-1999. (Pothole numbers averaged 6.6 million for the earlier time period and 6.2 million for the latter.) This represents a 12 percent productivity decline.

The most recent Harvest Information Program data also shows the high kill of adult mallard hens is continuing. Adult hens accounted for 38 percent of the hen mallard bag during the years 2000-2002. This is significantly higher than the 28 percent reported for the years 1994-96.

Waterfowl management must bear responsibility for this regulatory double-whammy. The evidence is overwhelming. Longer seasons and larger bag limits increase the adult hen kill. Earlier opening dates in northern states increase the kill of juvenile hens – juveniles needed to buffer the kill of adult hens on the wintering grounds. Later closing dates in wintering states put added gunning pressure on the surviving adult hens. Spinning-wing decoys throughout the nation disproportionately attract hens to waiting guns throughout the season.

Adult hens are the cornerstone of waterfowl hunting. The future of our sport depends on preserving our most productive breeders. Why has the U.S. Fish and Wildlife Service, as well as the flyway councils and Ducks Unlimited, ignored for the past decade the increased kill of the most valuable portion of our breeding stock? Why has it failed to protect the older hens critical for the preservation of biological productivity and the future of wildfowling?

These questions demand an answer, along with the imposition of regulatory restrictions to halt the profligate killing of our best breeders.