As Alberta’s migratory water birds return to the province, you’ll see them out on waterways, feeding and preparing for breeding season in the north. If you stop to watch them long enough, you’ll notice a key difference in behaviour between duck species: some of them tip their tails skyward to forage in the water, and some disappear under the surface entirely.
Mixed ducks by Gerald Romanchuk.
Waterfowl that upend themselves to forage in shallow water, like ponds and puddles, are known as dabbling ducks. When their tail feathers are in the air, their long necks are probing beneath the water, searching for vegetation to feed on. However, it’s very rare to see them dive all the way under the surface of the water. Some waterfowl species do just that, and zip beneath the surface, often appearing a substantial distance away from where they were first seen. Let’s get into some details!
Diving Ducks
Bufflehead by Patricia Bruno. Buffleheads are diving ducks.
Diving waterfowl, as the name implies, tend to dive for their food. They tend to rely on vegetation less than dabbling ducks, but both diving and dabbling ducks eat a combination of plants and invertebrates. Some divers eat exclusively fish! As a result, these piscivores (fish-eaters) also prefer deeper waters, like deep lakes or rivers, or coastal areas. Diving ducks tend to have their feet set further back towards their hind ends, so they often don’t move as well on land. They also need to gain momentum on the water’s surface before taking off for flight. Examples of diving ducks include the Canvasback, Goldeneye, and Mergansers (shown in order below).
Image credits: Canvasback (male) Judy Gallagher, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0>, via Wikimedia Commons | Goldeneye by Doris May | Red-breasted mergansers by Gerald Romanchuk
Dabbling Ducks
Dabbling ducks, rather than diving, simply tip their hind ends towards the sky and submerge their heads in water to browse on aquatic plants beneath the water’s surface. This means they typically favour shallower waters. They also tend to swim with their head and tails both above the water’s surface, and they don’t need to gain momentum to take flight like diving ducks do. They can just spring into the air! Dabbling ducks also have the unique characteristic of having an iridescent speculum (rectangular patch of colour) on the dorsal (back) side of their wings. Another distinction is that their feet tend to be smaller than their diving counterparts, and they tend to walk well on land. Examples of dabbling ducks include Mallards, Blue-winged teals, American wigeons, and Gadwalls (shown in order below).
Image credits: Mallards by Gerald Romanchuk | Blue-winged teal by Lu Carbyn | American wigeon by Gerald Romanchuk | Gadwall by Gerald Romanchuk
Why the Difference?
Ruddy Duck near Ministik Game Bird Sanctuary.
Both categories of duck do this for different reasons, and each one is suited for a different kind of habitat. Diving ducks tend to have long, narrow wings, better suited to more open habitats like large lakes, large rivers, and coastal regions. Dabbling ducks tend to inhabit more enclosed habitats, such as forested wetlands, which informs their physiology as well – dabbling ducks have broader wings, and aren’t as long as a diving ducks’.
Animals are shaped by their habitats and food sources, and these two categories of ducks are a perfect example of this. While dabbling ducks fly nimbly through forested areas and wetlands, bobbing for their meals, diving ducks soar over deep bodies of water and explore deeper underwater for food. These ducks all have one thing in common, however: they require intact habitats to feed, breed, and live. Central Alberta has seen a decline in the water levels of many lakes, and this makes the preservation of wetlands and riparian areas especially crucial.
By supporting local nature organizations like EALT, you help make sure that these wonderful waterfowl have homes to come back to each spring. Get involved by volunteering, donating, or simply spreading the word about us to friends and family.
Thank you for reading!
Sources:
Special thanks to Gerald Romanchuk for permission to use his photography.
