My hunting partner identified the approaching ducks as mallards while they were nearly 300 yards distant -- not an easy call. But he had to accept my word for it when I whispered that the bird on the left was a male, the other a female, and the two were almost certainly a mated pair. Instantly, he locked his gaze on the drake. It did not matter that the ducks shifted positions several times before coming in. When it came time to shoot, he cleanly killed the drake 30 yards out over the decoys.

We were hunting California’s Sacramento Valley during the first week of January, guests at a club whose managed wetlands attracted most of the Pacific Flyway’s dabbling-duck species. That morning the ducks had been putting on quite a show. We were easterners who were not used to seeing such a sustained flight of ducks, despite our host’s expressed concern that duck numbers were obviously down.

As we watched the frightened female fly off, my companion asked how I could identify the drake when the ducks were little more than black specks in the distant sky. I told him that initially I made an educated guess. I had watched the two birds for some time before they started working the decoys. From their size, shape and pattern of flight, I was reasonably sure they were mallards. Then, when I looked more closely, it became apparent one bird was slightly larger. I suspected it was the male, and became convinced only after observing the bigger bird follow the smaller. The drake obviously was taking his cues from the hen. Furthermore, we had been hunting for three days and virtually every duo of mallards we had seen consisted of a drake and hen, so two mallards together were a good bet to be a mated pair.

For many hunters identifying ducks, even those within shotgun range, is a challenge. Numerous studies have found that few hunters become more than mediocre at identifying flying ducks. This should not come as a surprise. Most hunt only a few times a year and, once the season is over and the guns and gear stored away, ducks are largely forgotten. Improving identification skills is a low priority in the lives of most hunters.

I am fortunate in having hunted ducks for 50 years while making a career of studying duck behavior. This has enabled me to sharply hone my identification skills

Improving your identification skills is a task that can be facilitated by knowing some key things about duck behavior. Some of this knowledge can be learned by reading, but much more can be learned by observing the birds in flight. This can be done while sitting in a blind or visiting some place (a refuge, for example) where the birds are undisturbed, hence relaxed and behaving naturally. As you gain experience, you will recognize flight patterns that reduce the guesswork.

The most obvious feature that hunters use to identify ducks is the color and pattern of plumage. Under some conditions this may be adequate, and it becomes a better indicator as the season progresses, but plumage is not always reliable and birds need to be relatively close. For example, that morning in California the location of our blind meant we were looking toward the sun, and this made identifying birds by plumage very difficult, even when they were in good range. This was true despite the fact that drakes of all species were in prime breeding plumage. Had my companion waited until he could pick out the drake using plumage as the only indicator, he may have passed up the optimum killing shot, perhaps missing the bird, or worse, crippling it with an ill-timed shot. There are many benefits to selective shooting, but there may be costs, too.

In general, plumage patterns vary depending on where and when you hunt. Northern hunters rarely see male ducks in full breeding plumage. This is because after the breeding season, males molt their colorful plumage, donning drab feathers that make them virtually indistinguishable from females. They gradually replace these feathers with colorful ones but the molt may not be complete until November or later, after the ducks have migrated southward. Similarly, the plumage of juvenile males hatched in the spring often resembles that of females until late fall.

Distinguishing males from females by plumage is very difficult for all hunters in the early season. When I was a kid growing up on the St. Lawrence River, the common belief among hunters was that male blue-wings migrated immediately after breeding. They knew this didn’t really add up but nobody ever saw, much less shot, anything but “females.” In fact, the blue-wings were gone by early October, long before males began to “color up.” I recall asking a Cajun guide in Louisiana about the local names of ducks. Without realizing it, he gave me two names for blue-wings, one for the drab bird he saw in September as it migrated southward, and the other for the colorful drake he saw in February returning on its northward migration after acquiring its courtship colors. He thought they were different species.

Similarly, male black ducks that are shot late in the season are known as redlegs, a “race” that many hunters believe migrates southward only after the northern freeze-up. In reality, these dusky males are the same birds they kill in October that have brownish-green, perhaps reddish, legs and feet. The ducks have not yet attained their breeding colors, which include red feet and legs. Pictorial guides to bird identification, including those produced for hunters, are usually useful only if the birds one sees are in full breeding plumage.

Hunters who are good at identifying ducks use plumage as only one of several indicators. Indeed, most rely more on features that don’t change with season. These features may be useful when birds are seen at a distance.

Knowing something about the social system of ducks is helpful. For example, ducks in late summer and early autumn congregate in mixed flocks of males and females. Their activities are primarily focused on finding food and avoiding predators. But the behavior patterns that most readily allow us to distinguish between males and females are sexual and, as such, they are not usually apparent until later in the season, perhaps as early as October for some species like mallards and black ducks, but usually later for the smaller dabblers.

As autumn progresses the behavior of ducks increasingly becomes sexually motivated, with males typically initiating interactions with females. At first this is low key, but it soon intensifies. By December all unattached male dabblers are looking for mates. They spend a significant part of their day engaging in courtship and other pairing activities. Because there are more males than females in duck populations, and most ducks are monogamous, there is keen competition among males for females.

The structure of flocks also changes with time. Early season flocks are larger and individuals tend to fly closer together. By mid-December flocks are smaller and usually consist of well defined pairs, males that have been unsuccessful finding a mate, and a few as yet unpaired females. Flock structure is now looser as pairs increasingly act independently, often avoiding other ducks, especially groups of males. Pairs may fly to feeding sites together with other ducks, but frequently these same pairs return to rest areas on their own. By January pairs are usually more numerous than single birds or flocks.

In fact, the number of birds you see in late season can be a clue in distinguishing between males and females. Two birds flying together are nearly always a mated pair. Even when pairs fly in small flocks, the male and female of each pair tend to stay close together. Typically, these flocks break up as the birds approach a landing site, with each pair landing some distance from the others.

Moreover, while male ducks are typically slightly bigger than females, this is a relative measure and a poor way of distinguishing males from females when they are alone or in groups. But size may be the best clue when dealing with pairs, even at a considerable distance. This is especially true with mallards and black ducks.

An exercise I do with my wildlife ecology students in Nova Scotia illustrates this. These students are rarely familiar with waterfowl. On a field trip I will point to two flying black ducks that I recognize as a mated pair and ask them to look for differences. The plumage of male and female black ducks is virtually identical. My students quickly identify body size as an obvious difference, but soon they see that the neck of the smaller bird is shorter. Some have the “sense” that the head of the female is smaller and perhaps sleeker in appearance, as opposed to the “chunkier” head of the male, but this is subtle. Within 20 minutes, all of the students can discriminate unerringly between males and females of pairs. Some are doing so intuitively, not able to explain exactly how they are making the discrimination. Single birds are much more of a challenge but a few students get quite good at identifying them after an hour or so.

An especially keen-eyed hunter can add a more subtle clue to the mix. This involves the way the male and female of a pair relate to one another while in flight. Early in the season the male tends to take the lead. However, the roles reverse as the season progresses and the now more sexually motivated male becomes increasingly attentive to the female, following her wherever and whenever she goes. By January, it is unusual for the male to make the decision to land or take flight. He takes his cue from his mate. Interestingly, the mallard and black duck trios that are so common by mid-December are predictably a mated pair – and an attached drake that hangs around. The two males are obviously larger and when in flight the second drake follows the pair.

When I travel I rarely make suggestions about setting decoys. It seems inappropriate and the locals usually know best how to decoy ducks in their area. Furthermore, I am there to learn. Still, we can all improve the skills required to get ducks into effective killing range. Decoying ducks is relatively easy in the early season and not just because ducks are naive about hunters. Feeding is their main activity so they are attracted to flocks of feeding or resting birds, which is what most decoy spreads simulate. Ducks then probably do not inspect decoys as closely as they do later. For this reason and the fact that males are motley in appearance, it is less important to have realistic, well-painted decoys in the early season. It’s sometimes surprising what northern hunters get ducks to decoy to.

There’s more of an art to decoying late season ducks, and not just because they’re now more experienced. Ducks are becoming increasingly sexually oriented and both males and females look closely at groups of birds to see where the males and females are. Decoys are well scrutinized. While unattached males are looking for females, paired females may avoid close proximity with other ducks. They don’t want their mates near other females and they don’t want to be harassed by other males. Experienced hunters leave an open space or two in their spreads for decoying ducks to land, but late season hunters may benefit from leaving plenty of spaces for pairs. Also, the association of male and female decoys is important. A spread that consists of widely spaced pairs and trios, perhaps with a group of six-to-eight males surrounding a female, is a natural-looking configuration. A little group of say three females in an open patch of water may pull in a drake who cannot believe his good fortune. Conversely, the same male might avoid a big, crowded decoy spread, the males and females of which are randomly scattered. This doesn’t look natural to the male who probably remembers the reception he got the last time he tolled to such a spread. Interestingly, many experienced hunters believe that ducks are getting smarter. An unrealistic decoy spread may be the reason why ducks flare well out of range for a careful and well-hidden hunter.

Small flights of tightly grouped birds late in the season are usually drakes that are hanging out together. However, courtship flights are a common sight in all species by late December. These dramatic flights consist of a female, one of the few who hasn’t yet chosen a mate, and several unpaired males. They may be fast moving and erratic or slow and “lazy,” but they are invariably characterized by males changing position in the flock as they jostle to get beside or ahead of the female so they can display to her. These birds sometimes fly over decoy spreads but the participants are not responding to the decoys and have no intention of landing.

A skillful caller significantly increases his chance of getting ducks over his decoys and into killing range. Here again a few insights into duck behavior increase his chances of success. With notable exceptions like wigeon and pintails, females do most of the calling that hunters are familiar with, and this calling is usually used to communicate with males, often in a sexual way. Hence, calling becomes more important as the season wears on. Its effectiveness depends on what is being called.

In general, pairs do not usually respond well to calling, particularly in the late season. Why would a paired female be attracted to the call of another female? However, the second male of a trio will often leave the pair to check out a calling “female.” He is very much interested in investigating the possibility that there is a lone female looking for company. Single birds are uncommon late in the season, and when seen they are usually males. For obvious reasons, these males respond well to calling. It is a good bet that lone females are birds whose mates have been shot. These females respond well to calling and decoy readily, because soon after losing her mate a female begins the search for another male. She is looking for a crowd and tends to be quite vocal.

All of this tells us duck behavior can be key to identifying ducks and attracting them within range.

For many years I have tried to shoot selectively, avoiding (as best as possible) the killing of hens and sometimes passing up shots at beleaguered species like pintails. I believe it contributes to the stability or growth of our breeding flocks. This is of great concern to me. There also is a personal reward. I find that observing duck behavior and using this knowledge to shoot only drakes is immensely satisfying. It makes me feel better about myself. It is my personal commitment to conservation, sportsmanship and the historic traditions of duck hunting.