By Kathy Rike
When walking around Lake Murray or Kumeyaay Lake, you may see birds that look like ducks and swim like ducks, but they aren’t necessarily ducks. Did you know that not all ducks dive and not all ducks quack?
The seven water birds discussed here are among the ones I have seen on my springtime hikes around the lakes. They are identified by name. Can you guess which ones are ducks and which aren’t? Some of their names will give you the answer to this question but others won’t.
The American coot is not a duck, although it often swims near ducks. It is a member of the rail family. Its thick, white beak is in stark contrast to its dark body. It dives for food but has lobed feet, rather than webbed feet. Interestingly, this bird seems to run on the water before taking off in flight.
The Canada goose’s name is a dead giveaway that it is also not a duck, although it is a part of the same scientific family along with swans. Its appearance is very unlike a duck due to its long neck. Geese have 17 vertebrae in their necks; ducks have fewer.
The gadwall is a duck. Both the males and females are nondescript looking with brownish plumage. You’ll find them in the deeper parts of small bodies of water. I saw two in a secluded part of Lake Kumeyaay in the area of the floating bridge, near tall rushes or sedges. They are dabblers rather than divers, getting their food by tipping over to reach vegetation they eat, which is near the water’s surface.
The lesser scaup is also a duck. They are winter visitors in San Diego. I spotted them swimming in Lake Murray in March before they migrated north for the summer. They are diving ducks looking for small invertebrates.
From a distance without binoculars you can see their distinctive black heads and black tails bookending what looks like a broad band of white on their backs. AllAboutBirds.org states that they “often look like they are doing somersaults or other odd acrobatics as they try to pick off the amphipods [small crustaceans] that cling to their belly feathers as they swim through the water.”
The mallard is a duck that many people recognize due to the male’s bright iridescent green head and neck. This duck is related to almost every breed of domestic duck and is commonly found in ponds and lakes. Mallards are dabblers like gadwalls. They reach the plants they eat by simply tipping over, head first.
The pied-billed grebe is a water bird but not a duck. Like the American coot, its feet are lobed rather than webbed, and are located near its behind. In fact, grebe means “feet at the buttocks.” Due to this positioning it uses its feet almost like a fish’s tail while swimming. It doesn’t fly well or navigate well on land, but it’s an expert diver looking for fish, crustaceans, and invertebrates.
The ruddy duck is a duck, of course. They can be found on both of the lakes in Mission Trails. This duck has a tail that typically sticks up at a 45-ish degree angle. The best view of the tail is from the side, in profile. The angle reminds me of the way a wren or wrentit holds its tail. It seems like the tail is too big for its body, at least for a duck! According to AllAboutBirds.org, ruddy ducks are sometimes harassed by other water birds including the pied-billed grebe, that attack them from underwater in a behavior aptly called “submarining.”
While walking in the park, don’t assume all birds you see on the water are ducks. Looks can be deceiving. And when you hear quacking, it is probably a female mallard — the only one in this group of birds that quacks.
— Kathy Rike is a trail guide at Mission Trails Regional Park.