One of the wonderful things about Dawn Chorus is that our visitors are birders and non-birders alike. Some folks stop by just to look at the pictures, some drop-in occasionally, and some of us are here every Sunday. Some are new to birding while others have been birders for years. That’s what makes it fun.
Today I’m going to talk about bird diets and what birds eat. I think if you were to ask the average person what birds eat, you’d probably hear “birdseed.” Or maybe “worms.” Obviously, those are correct answers, but most of us know that bird diets are broader than that.
Animals fall into three distinct groups based upon what they eat. This is a natural way to often group animals. Plant eaters are herbivores, meat eaters are carnivores, and animals that eat both plants and animals are omnivores.
Those are simple and basic categories. But when researching bird diets, I came across several additional categories when talking about birds. The following info comes from Melissa Mayntz who writes for The Spruce.
Avivorous
An avivorous bird eats other birds. This is a popular diet for many of the smaller raptors, such as accipiters, which often prey on backyard birds. In the picture below, which I got from the internet, a female American Kestrel has downed a pigeon. Several larger raptors will also prey on doves or pigeons. Red-tailed Hawks and Peregrine Falcons in cities are top avivorous raptors since pigeon populations are so abundant in urban areas. Large raptors may also take ducks or other waterbirds as prey when available. (When I searched for the photo below, I also found a hawk with a mallard but I’m too squeamish to choose that example. All the other photos in this post have been taken by me.)
Carnivorous
Carnivorous birds eat meat, including rodents, mammals, fish, amphibians, and reptiles. All birds of prey are carnivorous, as are many other birds including different shorebirds, corvids, and wading birds. A carnivorous bird may hunt and catch its own meat, or it could also prey on carrion. Vultures are carrion-eating carnivores, and many other birds will also sample carcasses as an easy meal.
I took the photos below at different times at the Yolo Bypass Wildlife Area. The below photo with the bittern was quite the scene. The bittern tried and tried and tried to eat that tadpole. It could never get it properly positioned and it finally gave up, dropping the prey and moving on. (I know it doesn’t look like any tadpole you’ve ever seen, but I circulated it widely among another group and it was identified as such by several people who said it was a tadpole of a bull-something I don’t remember. (Matching mole, any clue here?)
The photo with the ibises depicts a scene not too different. There are two ibises in the photo. The one with the crayfish kept trying and trying to eat it, but the crayfish was having none of it, twisting and turning constantly. The ibis dropped it and ibis #2 stepped in and grabbed it, repeating everything ibis #1 did to no avail. This was repeated a few more times until the crayfish dropped and neither ibis could find it again. It was pretty hilarious to watch.
Frugivorous
Frugivorous birds, or frugivores, are fruit-eating specialists. Orioles, waxwings, and toucans are all frugivorous and will eat fruit, berries and fruit-flavored jelly in the backyard. Many other birds will also sample fruit, including thrushes, grouse, quail, jays, wrens, tanagers and even some finches and sparrows. Many tropical birds also eat fruit. Frugivorous birds may be considered pests in orchards.
I took the photos below at various points in the last couple of years. The Yellow Warbler I found on a popular trail near Putah Creek in Davis. The Cedar Waxwing was in my own yard. And the crow was photographed at the Sacramento City Cemetery.
Granivorous
A granivore eats primarily grains or seeds. Many birds are granivorous, including many sparrows and finches. These are easy birds to attract to the backyard with different types of birdseed. Planting seed-bearing flowers in the yard or opting for ornamental grasses are easy ways to provide natural foods for granivores. Many of these birds also eat large amounts of weed seeds or spilled grain in fields.
I have three types of feeders in a raised bed with shrubs and flowers in front of my dining room window. Lots of birds show up to help themselves. I have a tube feeder that lets several birds perch at once. I also have a platform feeder shown in the photo below that all the birds love. The feeder seen in photo #2 is a nyjer seed or thistle feeder. The thistle is what American Goldfinches prefer, but the occasional House Finch will eat it, too.
Insectivorous
Insectivorous birds are specialized carnivores that feed on insects, from gnats to mosquitoes to dragonflies. Flycatchers and warblers are insectivorous, and most birds will eat insects to feed hatchlings sufficient protein for healthy growth. Other types of birds that are primarily insectivorous all their lives include swallows, swifts, martins, dippers, and nighthawks.
Molluscivorous
A molluscivorous bird feeds on mollusks such as snails, slugs or oysters. Many shorebirds are molluscivores and will forage at low tide for clams and oysters. Other molluscivorous birds forage in tidal flats or swamps. Limpkins are mollusk specialists, and many other wading birds and corvids also eat mollusks. A molluscivorous bird may drop its food from a great height to help crack tough shells, so the meat is easier to access.
Nectivorous
A nectivore feeds on flower nectar, and the most well known nectivorous birds are the more than 300 species of hummingbirds in the world. Other popular nectivores include honeycreepers and sunbirds, and nectivorous birds will visit both flowers and nectar feeders. Many other birds will also eat some nectar, including finches, woodpeckers, chickadees, and orioles.
I have an oriole feeder, in addition to my four hummingbird feeders. I have a pair of Hooded Orioles who come to the feeder several times a day, although they’re tapering off now. They’ll be heading south soon, as they spend the winter in Mexico. Unfortunately, I don’t have any photos of them at the feeder, but they’re gorgeous, especially the male (of course).
Ophiophagous
An ophiophagous bird is a snake-eater, a specialized type of skilled carnivore. The snake eagle family of birds are ophiophagous, and the secretary bird is one of the most well-known snake-eating birds. Many larger wading birds, such as herons and egrets, will also eat any snakes they can catch. Raptors, including hawks and owls, will also catch and eat snakes.
I’ll be honest, I’d never heard of the word ophiophagous before reading of it in this description. And I know it doesn’t look like it, but that hawk below is definitely staring down at the snake it had just dropped into the grass. The snake was hanging from its mouth and as I raised my camera, the hawk dropped it. Just like all the times I’ve been ready to press the shutter release when I’ve just gotten a bird in focus only to have it fly off at that instant.
Piscivorous
Piscivorous birds are carnivores that enjoy a diet of fish. The most well-known piscivore is the osprey, but other raptors, mergansers, and cormorants are piscivorous. Penguins, puffins and other aquatic birds are also largely piscivorous. Some of these birds may cause problems in sport fishing areas because they consume so many fish, and they may be culled if the problem is severe.
Here I have four photos that tell a story. As noted above, one species of fish eaters is the merganser. I was out birding at Bodega Bay a year or so ago and spotted this Red-breasted Merganser swimming around with a fish in its mouth. It wasn’t eating it but was holding it in its mouth as it paddled around hither and yon. It seemed to be showing off. This went on for several minutes as I watched. Even the Bufflehead in the background paid no attention.
Suddenly, a duck appeared from out of the blue and obviously noticed the merganser’s fish and started to make a beeline to grab it. The merganser hadn’t noticed it yet.
The commotion attracted the attention of another merganser who came barreling in, aiming for that fish, which the first merganser was still just holding in its mouth, content to just lazily paddle around with its prize.
As the second merganser and duck close in, our little fish hoarder sees that the jig is up and promptly swallows the fish before a fight breaks out. You can see just a bit of the fish that hasn’t yet been fully swallowed. As mother always said, don’t play with your food!
Omnivorous
The term omnivorous describes the diet of many birds – eating everything and anything. Ducks are well-known omnivores, and many birds will at least sample other types of food even if they prefer one type of diet more exclusively. To be considered omnivorous, a bird should have a widely varied diet and eat all types of foods, rather than showing just a few strong preferences.
When I read this description of omnivores, ducks weren’t the first birds I thought of. No, for me the birds you see hanging around every county dump because they’ll eat ANYTHING is the good old scavenger, the gull. My proof is below.
So in the end, we realize birds will eat just about anything to survive. So would we all, if necessary. It’s Labor Day weekend and lots of folks are out of town enjoying this last summer weekend, so we’ll likely have fewer commenters and visitors today. But today is actually my birthday, so I’ll be around till about 1pm PDT when I’ll leave to celebrate with friends.
The floor is open for all your comments, stories, questions and other things birdy. What’s going on in your birding world?