In North America, waterfowl are one of the most diverse groups of birds that most of us are likely to see on a regular basis – over 40 different native species alone – and unlike most passerine birds (small, perching birds like pigeons, warblers, and sparrows), waterfowl are quite conspicuous.
This diversity can be a little overwhelming for a novice birder. I can still remember when I first realized that the flocks of ducks on my local lake actually included a dozen or more distinct species. It was an eye-opening experience, and also a bit dizzying: I wondered how I’d ever learn to tell them all apart.
You may be in the same place I was then, not so long ago, just beginning to recognize the diversity of those birds that were, until recently, just plain “ducks.” A great place to start is simply learning the difference between different types of waterfowl, so you have a place to start in identifying the birds you see.
Among North American waterfowl, two of the most commonly seen types are ducks and geese. Both are part of the same large family of birds, Anatidae, which also includes swans, mergansers, and shelducks. Ducks and geese have some common anatomical and life history traits: webbed feet, broad bills, and a semi-aquatic lifestyle are just a few, which explains why they’re often confused.
Even so, ducks and geese are easy to tell apart if you keep a few general rules in mind. Geese are generally much larger than ducks, with longer necks and stouter, heavier bills. Even accounting for variation among species — and there’s plenty, considering the diversity of the family Anatidae — these traits will help you to keep your ducks and your geese separate.
Size & Shape: Goose vs Duck
Geese are almost always larger than ducks, and often by a very wide margin. The difference is especially pronounced between ducks and domestic geese, which are bred for size, but the difference is quite apparent even among wild birds. For example, the smallest goose North American goose, the Ross’s Goose, still has a substantially greater wingspan (114 cm/45 in) than our largest true duck, the Canvasback (85 cm/33.5 in).
Of course, there is a great deal of variation between species and individuals within each group, and some domestic ducks can be quite large. The Muscovy Duck, a common domestic duck on American ponds and lakes (easily recognized by the red wattle around its bill), may be much larger than the average wild duck.
Ducks and geese also have different body shapes, which give them very distinct appearances. Geese have long, s-shaped necks, while the necks of ducks are shorter, thicker, and straighter. The difference is especially pronounced in flight, when both birds extend their necks fully.
Geese have longer and more robust legs than ducks; on land, they often have an upright posture. Ducks on land generally look like ducks on the water, with a horizontal posture and waddling gait.
Naturally, there are exceptions to all of these rules, but these generalities are quite consistent, and if a species is exceptional in size, it will usually be typical in shape (and vice versa). For example, some species of ducks, like the whistling ducks, have long necks and somewhat “goose-like” posture – but they’re so much smaller than geese that they are unlikely to cause confusion. Muscovy Ducks are closer to geese than to other ducks in size, but their thick necks and stubby legs are very duck-like.
Bill: Goose vs Duck
Although not as obvious as size and proportion, the bills of ducks and geese also make for excellent distinguishing features. Geese have stout, wedge-shaped, and pointed bills, with the nostrils about halfway up the length. Ducks’ bills are much flatter and slimmer, often rounded or blunt at the end, and the nostrils are higher on the bill than those of geese.
While generally applicable to freshwater species, take this rule with a grain of salt, because there are plenty of exceptions and qualifications. Seaducks like eiders and scoters, for example, have thick bills easily mistaken for a goose’s – and then there’s the Egyptian Goose, a common domestic species that is actually neither a goose nor a duck, and has a bill that looks a little like both. However, for most freshwater species bill shape will be easy to spot and a reliable distinguishing trait.
Ducks and geese, despite their family resemblances, are very different birds. Geese are larger, bulkier, and have longer legs and necks. Even for exceptionally large ducks and small geese, bill shape will easily untangle potentially confusing birds.
Of course, knowing what kind of waterfowl you’re watching is only half the battle: there are dozens of species of native ducks in North America, and at least seven species of native geese – and that’s not counting domestic species and varieties, which are numerous and widespread.
Still, understanding the differences between big groups of birds is important, and something to be proud of. Waterfowl are tremendously diverse, and being able to sort your birds into smaller groups will make identification a little less overwhelming. Best of all: once you start to pay attention to these birds, you’ll start to see the amazing variety of birds that can be found on even the humblest ponds, and your world will be a little richer.
Goose vs Duck Comparison
|Canada Goose||Mallard Duck|
|Scientific name||Branta canadensis||Anas platyrhynchos|
|Length (both sexes)||76-110 cm (29.9-43.3 in)||50-65 cm (19.7-25.6 in)|
|Wingspan (both sexes)||127-170 cm (50-66.9 in)||82-95 cm (32.3-37.4 in)|
|Weight (both sexes)||3-9 kg (6.6-9.8 lbs)||1-1.3 kg (2.2-2.9 lbs)|
|Bill||Black, wedge-shaped in profile, much shorter than the length of head; culmen beginning at eye level, with nostrils halfway down the length of the bill||Yellow or dark brown, flat, and rounded; about as long as the head; culmen beginning below eye level, with nostrils placed about 1/4 of the length of the bill|