This time of year, everyone’s chomping at the bit for spring. Whether it’s that little extra bit of daylight, the first glimpse of a woodland wildflower or the rattling calls of sandhill cranes waaaaay up in the sky, we’re all eager to reach out and grasp the promise of warmer days to come.
But before we get too far ahead of ourselves and our dreams of blossoms and sunshine, I’d like to encourage you to slow down just a bit and absorb the glory of early spring – even though I know our March landscape looks pretty drab with plants still dormant in dull grays and browns. Last year’s leaves are long gone (and hopefully decomposing near where they fell, so that their nutrients can be returned to the soil), while this year’s foliage has yet to appear.
But that, my friends, is where the benefits lie. With no leaves on the trees, we can look at one of the greatest treasures their branches hold: empty nests.
Those delightful creations of yore, made by creatures who don’t even have hands, let alone construction adhesive and power tools, are still clinging to branches, twigs and stems. And with just a little careful study, we can learn a great deal about our tree-dwelling neighbors.
By examining the materials used, you usually can figure out who the builders were. Here’s a little look at some of our area's most commonly seen nests:
Grass and mud: These nests are the work of the American robin. Grasses and other plant stems are formed into a cereal bowl-sized nest anchored by mud. A quintessential nest, if there ever was one, these creations are found 10 to 20 feet up in trees or, frequently, on porch columns, outdoor light fixtures and other ledge-type features of human-built structures.
Small cup lined with hair: Some artists work in oils or watercolors. The chipping sparrow works in hair. These birds construct their nests rather low, usually less than 10 feet from the ground; they collect grasses and plant stems for the bulk of the structure, but use hair or fur to provide a soft bed for the eggs and subsequent nestlings.
Small cup lined with plant down: These nests are the handiwork of the American goldfinch. Look for them in in forks of branches in small trees in or near open fields where thistle – a goldfinch favorite – grows. The cup is very tightly woven and features the silk of caterpillars and spiders as binding agent.
Mesh-like pouch of plant fibers: If you see a pendulous nest of intricately woven strands of plant, looking like a basket (or, to me, a softball stripped of its leather cover), you’re looking at the remarkable creation of a Baltimore oriole. In our area, these nests usually have a bit of suburbia woven in – a ribbon here, a strand of Easter grass there. Horror of horrors, sometimes the nest contains fishing line. More than once I’ve seen a bird, dead, hanging beneath its nest at the end of a length of 8-pound test.
Big bowls made of sticks: These are the work of our area birds of prey and, like the Three Bears’ beds, come in small, medium and large sizes. Smaller constructions, measuring around 2 feet in diameter, are the work of Cooper’s hawks; those around 3 feet are made by red-tailed hawks; and those the size of Volkswagens are built by bald eagles. Stick nests have a few important side notes worth mentioning:
If you see a whole lot of stick nests in close proximity to each other, in trees or near water, you’re looking at a rookery. In our area, great blue herons, great egrets and cormorants are our most common rookery builders.
Great horned owls do not make their own nests, but are fans of stick nests and often appropriate them for their own use during winter, which is their breeding season.
Big balls made of leaves: These nests aren’t made by birds at all, but rather by squirrels. The structures look flimsy, but actually are quite strong, with underpinnings of twigs and other pliable material to lend form and structure. Squirrels usually will have at least two leafy nests (also called dreys) at any given time, and also adopt tree cavities should the opportunity arise.
Basketball-sized paper nests: Bald-faced hornets build these nests, which start out small and grow over the course of spring, summer and fall. By the time we see them, it’s often fall or winter, and the inhabitants have been killed by frost. But you know what’s really cool? All the dead adults and frozen larvae are a phenomenal food source for birds, squirrels and other wildlife.
With all this talk of nests, I think it’s important that all nests are protected by conservation laws and need to remain in place even when they’re no longer being used. (At Hickory Knolls we actually have two permits, one from the Illinois Department of Natural Resources and the other from the U.S. Fish and Wildlife Service, allowing us to display the nests in our collection.) These rules date back to a time when nests and eggs – and feathers – were collected and sold, often to the detriment of the species.
But there’s no law against looking! Next time you’re out, or even just gazing out a window, scan the trees for globs of different shapes and sizes. Be sure and do it soon though. Before we know it, the leaves will be out on the trees, and we’ll have to wait ‘til next winter to go on an empty-nest treasure hunt.
(Pam Otto is the manager of nature programs and interpretive services at the Hickory Knolls Discovery Center, a facility of the St. Charles Park District. She can be reached at 630-513-4346 or firstname.lastname@example.org. Feedback on this column can be sent to email@example.com.)