I'm old enough to remember the good old days of the mid-1950s when back-to-back “Grand Passages” (1954 and 1955) produced spectacular migrations. Moreover, I remember the early 1960s when there were a 23-day season and two-bird limit (one mallard).

I also well-remember the last four years, which have been less than sterling. If you are like me, you worry that we're not just in the downward phase of a cycle of ups-and-downs, which we have had ever since we first began keeping records, but in the throes of a long-time decline in waterfowling.

In my last column, I gave some anecdotal evidence on spinning wing decoys (SWD). In this column, I will give some scientific facts.

California studies found their hunters killed 66 percent of their mallards when using spinning wing decoys. They also found that the age-ratio averaged 3.2 juveniles per adult from 1996-98, compared to 2.7 juveniles per adult from 1999 to 2002, a decline of 16 percent. At the same time, the average mallard kill declined 26 percent, dropping from 378,000 in 1996-98 to 281,000 in 1999-03. Since the onslaught of the spinning wing decoys, the percentage of adult hens in the female bag has increased, a factor that has significantly reduced juvenile productivity.

Manitoba studied the results of leaving spinning wing decoys “on” for 30 minutes and “off” for 30 minutes. In the field, leaving spinning wing decoys “on” were 24 more times successful in a kill, while in the marshes spinning wing decoys were five times more effective. In Missouri, hunters killed 1.28 more total ducks per hunting party when spinning wing decoys were turned “on” than “off.”

Arkansas did a similar study and found 1.8-to-1 higher kill rate with than without. Most of the kills were juveniles. Since the 1960s, Arkansas has had a .75 to .80 ratio of juveniles killed for every veteran duck killed. In the 2002 season, it was .53. Flyway-wide, it was .90.

In 1990 in Iowa, the ratio was 1.28 juveniles killed per adult hunter. In 2001, that number more than doubled to 2.62. Wisconsin had a ratio of 1.22 in 1990, but had almost tripled to 3.01 in 2001.

Minnesota had a ratio of 1.40 in 1990 and a ratio of 2.55 in 2001. One year later, a study found the mallard kill rate averaged 4.71 times higher when spinning wing decoys were turned “on” than “off.” In addition, the size of responding mallard flocks was 1.25 times larger when spinning wing decoys were turned “on” than “off.”

The bottom line reveals the northern states in the flyway are killing the juveniles, while the Southland is killing the superhens. The only birds left are veteran birds.

Reports from Canadian hunters — Alberta to Ontario — this past season confirm that the birds in their area were veteran birds: tough to call, difficult to decoy, fixated on refuges, and most of all, untouchable veterans. Reports from the upper and lower regions of the Mississippi Flyway were the same.

Many believe that spinning wing decoys should be banned because they overstep the ethical bounds of fair chase and increase harvest above acceptable levels. Others favor the use of spinning wing decoys, believing the devices attract ducks closer, thus reducing crippling and enabling hunters to selectively harvest drakes over hens. Studies do not prove this.

My problem with spinning wing decoys is that we're killing the juveniles in the north and the veterans (including the superhens) in the South. By killing the latter, we're insuring ourselves of poor seasons ahead, as fewer veterans return to the breeding grounds to reproduce — whether the habitat is ideal or not. Moreover, those that survive know where to go to find food and sanctuaries: refuges.

Just six states have imposed partial or total prohibitions on spinning wing decoys; no federal regulation limits their use. The Arkansas Game and Fish Commission has banned spinning wing decoys for the upcoming season.

I credit a great deal of the last four years of waterfowling decline to spinning wing decoys. Once outlawed entirely, it'll take years to recover, because they've done irreparable damage.


Wayne Capooth — outdoorsman, writer, and physician — has hunted extensively in Tennessee, Mississippi, and Arkansas for 50 years and has written four books. On the Internet, go to www.waterfowling.org.