Keep Looking Up: A Guide to the Nests of Sharon

By Kurt Buermann

I think when we walk or hike, our usual habit is to look from side to side, or at the ground. Less frequently do we gaze upwards. Some time ago, I was fortunate to spot a great horned owl. I would never have seen it except for a couple of red-winged blackbirds who were making a commotion around its head hoping to oust it from its perch. (They did not succeed. The great bird was trying to enjoy its daytime sleep and had probably put in earplugs. It was completely oblivious to the redwings’ harassments.) The incident served to make me more aware of the world over our heads in the woods. At the risk of falls and sprained ankles I now tend to amble along with my attention more focused on the branches above than the ones lying across the path. There are days when nothing much is happening on the forest floor but there is almost always something of interest in the trees and limbs overhead.

Squirrel Dreys
Perhaps the most common arboreal dwellings in Sharon’s trees are the squirrels’ nests. These have few if any visible twigs. They resemble great big, somewhat misshapen, leafy balls. The squirrels live snugly inside the nest chamber. I am always amazed that the flimsy-looking leafy constructs don’t blow away on the first breezy day. Squirrels build two types of nests, called dreys. There are winter dreys and summer dreys. The cold-weather nest is built in layers with linings made from hair, fur, moss, and grasses. A special chamber serves to keep babies warm. The summer dreys are less likely to be used for litters and are more hastily and loosely thrown together.

In the dark hours the squirrels’ nests are a secure refuge from the hungry eyes of owls, notorious (in the squirrels’ opinion!) predators.

Hawk Nests
If you see a large nest made up of sizable sticks, this is probably the nest of a hawk. In Sharon the Cooper’s and red-tailed hawks build large 18 to 30 inch diameter nests of large sticks. These are distinguishable because of their size. Unfortunately, crows also build sizable nests, so without observing the birds at the nest it may be difficult to distinguish hawks’, crows’, and larger birds’ nests. If you are near water and see a very large nest perched atop a tree—or sometimes on a phone pole or high atop a power line tower—it is likely to be an osprey nest. Interestingly, you can sometimes get a hint about the species of the builder from the location of the nest—whether it is built in a limb intersection, out on a limb, near the trunk or higher or lower in the tree. Unless you wish to charter a helicopter, you can find more detailed nest identification information in two books, listed at the end of this article.

Speaking of helicopters, it is always advisable to keep your distance from nest-building activities. Some birds are very shy and get easily upset during breeding and nesting times, and they may abandon the nest you are observing only to have to expend precious time and energy to relocate and rebuild if they are disturbed.

Heron Rookeries
In Sharon there are several heron rookeries. The heron nests are very high up and difficult to observe. Usually they are in tall pine evergreen trees where the foliage helps to hide them. If you see herons flying across the town, you may notice that they fly along definite routes, going out in the morning and coming back in the evening. In many cases they are flying to and from the rookery—a usually secluded spot where a colony of herons may maintain many nests. Made from large thick sticks, heron nests are used and reused as the herons return to the same place each year to raise an new generation.

Oriole Nests
Orioles construct a round “basketball” which is usually suspended from the end of a drooping branch. In the fall or early spring before the foliage returns, it is interesting to try to locate oriole nests. The birds may well return to the area. Once the leaves are out, it can be almost impossible to find these nests. Oriole nests should not be confused with large hornets’ nests which are also revealed in the leafless months. The hornet’s nest looks as if it were impaled in the branches and has a grey papier-mâché look. Orioles’ nests more resemble woven balls.

Owl Nests
Ever since spotting the great horned owl mentioned above, I have been sort of owl-happy. Careful scanning of trees is needed because of the excellent camouflage afforded owls by their plumage. Spotting an owl is often due to just dumb luck. Sometimes smaller birds will raise the alert and flutter and twitter around an owl hoping (against hope) to drive it out of their neighborhood. One time, a crashing in the treetops alerted me to a fledgling great horned owl trying to learn to fly. Keeping altitude was no problem, but it hadn’t quite mastered the art of avoiding small twigs and branches. It would have to practice more if it were to live up to its reputation as a silent-winged raptor of the night.

Owls in general prefer to nest in cavities in trees, or in nesting boxes if they are fortunate enough to find one. I always try to carefully inspect any holes or hollows in tree openings with binoculars. Frequently, owls may make use of a second-hand hawk’s nest, giving it a quick once-over and new lining. Owls are often poor nest-builders, and shoddy construction sometimes is the cause of failed breeding efforts. One way to locate owls’ nests is by looking around the bases of likely trees for disgorged pellets containing fur, bones, and indigestible parts of prey. Yucky, but a sure sign of owls in the vicinity.

Raccoons and Minks
Not only avians are to be found in trees. I have spotted raccoons happily dozing on the high limbs of a pine tree. It took me a while to decide what kind of bird they were! There was one evening when our small (but resolute) cat had treed what I first took to be two other grey cats but which turned out to be minks. Once I had scooped up our foolhardy one, the two came down and bounded away toward a stream in the woods with their characteristic porpoise-like leaps.

Trees can tell other stories. If you find broken, fresh wood and splinters on the ground, it means lightning has struck. Often the electric current will leave a long, narrow groove down the length of the tree. In most cases the tree survives.

A fruit tree such a mulberry is a magnet to many bird species. If you want to see cedar waxwings or orioles, wait near a mulberry tree.

I would strongly recommend a walk in the days before the leaf canopy spreads. A casual survey of the treetops can lead to happy discoveries.

Books:
Guide to Bird Behavior by Donald and Lilian Stokes (3 vol.) (Little, Brown and Company). A description of nests, behavior and detailed information for most common bird species. ISBN 0-316-81726-0

Guide to the Nests, Eggs and Nestlings of North American Birds by Paul J Baicicch and Colin J. Harrison (Princeton University Press, formerly by Academic Press). ISBN: 0-120-72831-1