The Breeding and Nesting of the Gray Catbird

BIRD COLUMN FOR August 22, 2004

By Benjamin P. Burtt

Topic: The Breeding and Nesting of the Gray Catbird Why does the male perch near the nest and flap his wings a lot?

Provided below is a copy of all the material that appeared in the newspaper column on the date above, plus extra information for the interested reader who wishes to learn more about this subject.

Here is a recent questionMr. Burtt: A pair of catbirds nests in my yard. One perches and flaps its wings for several seconds, then flies off, perches again and repeats the flapping. What is going on? W.M.-Cazenovia

CAPTION: The catbird is a gray bird with a black cap and an almost black tail. There is a distinctive rusty patch of feathers under the tail. See the arrows in this painting by Roger Tory Peterson in his "Field Guide to Birds of Eastern and Central North America". While the catbird is an excellent singer, it sometimes makes a cat-like mewing sound. (Courtesy of Houghton Mifflin Co.)

Dear W.M.: These motions are part of the way that the bird communicates with its mate and with other birds. Before we discuss the "wing flapping" and what it means, it will be helpful if I first review how birds do communicate.

How Birds Communicate

Making calls or songs

Making sound is the most obvious way that birds interact with each other. One of the types of sound we refer to as "song". This is perhaps a poor choice of words. Humans often sing to express a joyous or perhaps a sad feeling. Does the bird really feel those emotions?

When we carefully watch what birds are doing as they make these sounds, it is possible to get an idea of why they do it. It seems clear that male birds make "songs" when they are trying to attract a mate and when they are making an effort to keep other males away.

Sometimes people say a bird is scolding, but such noise is often made to announce to all other birds in the vicinity that a predator has arrived and is threatening a bird or its young. Other birds are attracted to the scene. When there is a large flock of different species diving at a predator and making lots of noise, the predator is less likely to capture even one for a meal.

Very young birds just out of the nest usually make sounds when they are hungry. A parent returning with food can easily find the hungry youngster. So the peeping sound is a means of communicating the baby's whereabouts.

Watching what birds do and how they interact with one another helps us learn what they are doing. It also adds a lot to our enjoyment of birds. However we really are not justified in attaching human-like emotions to the things birds do.

Communicating with body movements

In addition to making sounds, birds can communicate by body motion such as head bobbing, wing flapping or tail motion or fluffing the feathers. These have meaning to their mate and in some cases to other species of birds. Careful study and observation helps us understand why a bird makes a particular motion.

Activities in the Spring

The gray catbirds return from the Gulf states and Central America in the spring. The male selects an area as the territory where it will have its nest. Usually this is in a dense thicket. It sings loudly from various perches in that territory to tell other males that this area is taken and that females are welcome.

When other males come close there are disputes. Both males will make the cat like sounds at this time. Such disputes involve some chasing by the resident male. The chasing and mewing seems to settle the matter.

The mewing sound is also given when a predator is spotted. Whether it is threatening to the predator I do not know, but the sound will certainly alert the birds mate that there is some danger.

Imitates Other Birds

The catbirds singing is a sort of mixed song with lots of notes and phrases. It also sings the songs of other birds. It has been observed to sing the song of the bluejay, the quail, several different hawks, the whip-poor-will and even a tree frog.

In the Southern states it was often called the "black mockingbird".

Now for the wing flapping

The female catbird does all of the incubation. She stays on the eggs for about 20 minutes at a time. Then she leaves the nest for 5 to 10 minutes to feed.

During this time, the male must stay within a few yards of the nest, "guarding" it so to speak. How do these two birds coordinate this "changing of the guard?"

It would be dangerous for the eggs or the nestlings if both parents were away from the nest at the same time. Some means of communication is needed if the female is to leave the nest and have the male watch over it. Usually, she leaves after the male has approached and made a soft call accompanied by flicking his wings in and out from the sides.

While on "guard duty" within a few yards of the nest, the male continues to flick his wings. This may serve to distract an approaching predator away from the nest. When the female returns to settle on the nest, he goes off to feed nearby.

There is another wing motion that is used as an alarm signal. It indicates that you are approaching the nest or a predator has come in sight. In this case the catbird holds its head, body and tail all in a horizontal line. The wings are stiffly raised to the sides and held there a moment and then it is done again. What you described as "flaps its wings" may have been this "raised wings" motion repeated several times.

It would also help our interpretation of the behavior if we knew whether or not the female was on the nest at the time you observed the “flapping”. If she was there, the male was probably just indicating that he was nearby. It would also help if we knew whether you were visible to the bird that was flapping its wings. If you were observed, the wing motions were more likely a warning that you were there.

Another display involves the fluffing up of body feathers until the bird appears to be quite large. This is done by the male when another catbird is challenging him. The “fluffing” is also used if a snake or other predator approaches, the larger puffed up appearance is more threatening and helps to drive away the invader.

Books about bird behavior

After many hours of careful watching, the meaning of these sounds and motions is diagnosed. Scientists write down their observations and they are published in a scientific journal for others to read and study. When there is general agreement on the meaning of the behavior, someone will write a book about it.

If we wish to learn about the behavior of a particular bird, we must find such a book and look up the gray catbird as I did.

Donald and Lillian Stokes have written three books on bird behavior with each volume covering a different set of species. They have sketches that show some of the types of displays and the most probable meaning of each display.

They were written over a period of years and each one has the words “Bird Behavior” in the title. If you have observed some unusual behavior, you may find an explanation in the book that lists that species. Try your local library.

In addition to their Guides to Bird Behavior, the Stokes have written a series of Nature Guides on each of the following subjects: Insect Lives, Wildflowers and Animal Tracking. All of these are useful and available in a good library

The killdeer and its Nesting Habits

BIRD COLUMN FOR July 25, 2004

By Benjamin P. Burtt

Topic: The Killdeer and its Nesting Habits , Precocial and Altricial Youngsters, A Young Killdeer that Disappeared while I was Staring at it. A Tame Quail

Introduction

Provided below is a copy of all the material that appeared in the newspaper column on the date above, plus extra information for the interested reader who wishes to learn more about this subject.

Here is a recent question: Dear Prof. Burtt: We have a brown bird that nested in the pebbles beside our driveway. When we approached the nest, the bird hobbled off like she was hurt and put her tail feathers up like a peacock. Her tail feathers are a lighter brown with some white. Please tell us something about this bird. —C. N., Marcellus, NY

Dear C.N: The bird is a killdeer. It is related to the sandpipers, but instead of feeding along the shore, it prefers plowed fields and pasture lands. There it eats worms, grubs and insects of various kinds.

There are two black bands across its breast. In flight, a golden-red rump is conspicuous and it has quite a long tail. It is a noisy bird and repeats its loud insistent call again and again: "kill-dee, kill-dee, kill-dee."

The Killdeer Is A Common Bird

The killdeer is the most common shorebird that breeds in Central New York. Shorebirds are those long legged, wading birds we see along beaches, lakeshores and muddy pools. The most familiar ones are the sandpipers that dash out into shallow water and mud flats to pick up little marine worms and other invertebrates.

The largest group are the sandpipers and the next most abundant are the plovers. The killdeer is a plover. Plovers are more compact and with a shorter neck than the sandpipers. The bill is shorter and stouter too.

Of all the shorebirds, the killdeer is one of the easiest to identify for there are two black bands across the breast as shown in the painting. In flight, a golden-red rump is conspicuous and it has quite a long tail.

CAPTION: This common shorebird, a killdeer, frequents pastures or fields rather than the seashore. Its well-camouflaged eggs are laid right on the ground with only a bit of gravel for a nest. The chicks leave the nest the day they hatch. This painting is from the Peterson field guide, "Birds of Eastern and Central North America", fifth edition ( Courtesy of Houghton Mifflin Co. )


It is a noisy bird and repeats its loud insistent call again and again: "kill-dee, kill-dee, kill-dee." Both its common name and its scientific name reflect this characteristic voice. The scientific name is Charadrius vociferus where the first word is the genus and the second part, the species name. The species , vociferous, is close to the English word, vociferous which means noisy or loud.

Practically No Nest

It lays its eggs in the open on the ground. Spots with gravel, cinders or pebbles are chosen where the eggs will be almost invisible. There is no real nest. It finds a small depression on the ground or perhaps scrapes a very shallow hollow. Now and then, it puts a few pieces of grass on the spot. The eggs are laid right on the ground. They have a lot of brownish blotches and spots on a buffy background.

The eggs are very large for the size of the parent bird. For example, although the killdeer and the robin are very nearly the same size, the killdeer's egg is twice the size of a robin's egg. It only takes the robin 13 days to hatch its egg, but the killdeer egg requires 26 days! There are some good reasons for these differences.

Killdeer youngsters are “precocial”

Young birds fall into two categories, depending upon how well developed they are when they hatch.

Altricial birds hatch in a helpless condition , most with their eyes closed, are unable to leave the nest and are wholly dependent upon their parents for food and care. Most are born naked . Examples are robins, jays and house sparrows.

The herons, hawks and owls are born with a covering of down, but they are still helpless.

Precocial birds hatch in the opposite condition in that they can move about soon after hatching and drying. They hatch with their eyes open, are covered with down and only partly or not at all dependent upon their parents for food and care. They leave the nest within a few hours of hatching.

Young killdeers are precocial. This does require something different. The young killdeers must be quite well developed by hatching time if they are to walk immediately. The large yolk mentioned above, provides the extra food they need while developing in the egg. A large egg and a longer period of incubation are required for precocial birds.

Generally, the chicks of helpless altircial birds hatch in sturdy nests in trees where they are protected from animals that walk about on the ground. Precocial chicks like the killdeer leave the nest immediately which gives them some protection from raccoons, weasels or other mammals that would devour helpless chicks in a nest on the ground.

Their legs are well developed, but their wings are very tiny and unfeathered. They cannot fly at this stage. The parents guard them, but do not feed them. The youngsters must pick up their own food.

Well camouflaged

I tried to catch a young one some years ago. He ran from me and then stopped suddenly. I moved in to drop my cap over him. However, I could not find him although he had stopped on an open patch of dirt right before my eyes. I stared at the spot and studied it for some time before I could make out his outline. When a young killdeer "freezes," its camouflage is almost perfect!

Broken Wing Act

When the incubating killdeer is disturbed on the nest, it puts up quite an act. If the intruder is a predatory animal such as a dog, a fox or a man that might want the egg, it flutters away from the nest with one wing hanging loosely as if it was injured.

Predators are strongly attracted to an injured bird (they are easier to catch I suppose). The killdeer moves a short distance away from the nest; beats one wing on the ground and the other will be twisted up over its back. This behavior together with its loud calling is enough to distract the predator away from the nest site.

Different tactics are used with a horse, a cow or deer. Such animals have no interest in the eggs, but they still might destroy them by walking over the nest.
In these cases, the killdeer seldom leaves the nest until the animal is just about ready to step on it. At that point, the killdeer flies at the face of the intruder and frequently strikes it on the muzzle. This usually causes the animal to retreat and the nest is saved.

The Little Quail

While on the subject of baby birds, I remembered a summer at Cape Cod many years ago. There, a little quail was the source of much delight to visitors to the Massachusetts Audubon Society's Wellfleet Bay Sanctuary.

This particular bird had been taken in by a local resident. Because of its small size and striped appearance, it was immediately named, "Bumblebee."

Bumblebee frequently fed at the family table where its cage was taken at mealtime. Later, when given a little more freedom, the bird formed the habit of sleeping on a blanket at the foot of its mistress's bed. The bird formed such an attachment for the woman, that it attempted to drive away friends who came to visit. It even attacked her husband.

In desperation, she checked with the Wellfleet sanctuary. They had some quail there in a semi-wild state in a fairly well protected area. Bumblebee was liberated there.

It adapted itself to life in the sanctuary and learned to feed for itself. Generally, it was seen by itself and was not quite accepted by the other quail there.

The little quail seemed to prefer human friends. On Sundays when visitors were there in large numbers, the quail got lots of attention. A visitor was often startled to see the little bobwhite pop out of the bushes into the path, tame and unafraid. It would walk up to people, "peep" and allow them to touch or pet it.

Young birds usually become attached to the first living creature they see. This is normally the parent. When a young bird is raised by humans, it becomes attached to them and does not know that this is a dangerous thing to do. It may later approach a human or some other moving animal and be killed. It probably will not recognize others of its own kind and so will never mate.

If you find a young bird, it is best to leave it alone. The parents are probably nearby and will take care of it. In addition, it is protected by law and it was illegal for the lady to have taken it into captivity.