Put up by Jen Berlinghof
The winter panorama, stripped of its lush layers of leaves and fields of flowers, reveals hidden houses. This season of stillness gives a glimpse into animal lives that have been carried on clandestinely all through spring, summer time and fall across the Lake County Forest Preserves in northern Illinois. It’s shocking to see what number of critters have been busy elevating households proper beneath our noses, or generally, proper above our heads, with out us all the time noticing.
For months in 2021, I walked from the parking zone at Ryerson Conservation Area in Riverwoods to the Welcome Center, previous the bioswales—trenches crammed with native vegetation that assist handle rainwater runoff, slowing the water down and filtering pollution—and I by no means had an inkling of the bustling hive hanging within the hackberry (Celtis occidentalis) tree alongside the best way.
Solely after the golden leaves turned a weather-beaten brown and dropped in crunchy piles did I spy the architectural mastery of the bald-faced hornet (Dolichovespula maculata). These basketball-sized nests are constructed in spring with paper-like materials produced from chewed wooden fibers blended with the hornets’ saliva. Bald-faced hornets construct the internal nest with layers of paper cells that seem like a honeybee’s comb, every chamber housing a person egg. These layers are then encased with a thick outer shell. A gap on the backside of the nest permits hornets to return and go simply.
Whereas a nest corresponding to this may home about 400 hornets throughout spring and summer time, it’s deserted come fall and sometimes destroyed by birds that feast on growing larvae inside. The fertilized queen is the one surviving member of the colony, and she is going to overwinter tucked into a close-by stump or rotten log for cover. She’ll emerge in spring to put her eggs and begin constructing a brand new nest. The queen gained’t use the nest from prior years, so I’ll not unwittingly stroll beneath a buzzing hive on daily basis come subsequent summer time.
Undiscovered fowl nests hid within the shrubbery are a standard sight in winter, as properly. One sort I’ve come throughout usually on current frosty treks are the dainty, snowflake-crusted cup nests of the American goldfinch (Spinus tristis). Females solely construct their three-inch abodes on the junctions of vertical branches of small shrubs inside open fields of sunflowers, asters and thistles. Hidden from view by clusters of leaves within the verdant months, the finches’ tightly woven, watertight nests are lashed to branches with sturdy spider silk and lined with downy seed fluff.
These vivid, sunny-yellow birds of summer time really stick round in winter, sporting subdued colours that make them a lot much less conspicuous that many individuals assume finches migrate south for the winter. Throughout their fall feather molt, American goldfinches develop a brand new set of duller feathers a lot denser than their summer time plumage, offering a further layer of insulation to assist maintain them heat. Although they abandon their nests after breeding, these feisty birds have been identified to burrow beneath the snow to type a comfy sleeping cavity to remain heat on a chilly winter’s evening. Hold look ahead to finches at your fowl feeders all winter lengthy.
Once I look larger, in the direction of the guidelines of the towering oak timber, I uncover one other animal nest that’s not essentially deserted in winter. What seems to be a giant clump of leaves with a couple of errant sticks protruding is in reality an eastern gray squirrel (Sciurus carolinensis) nest, or drey. Whereas squirrels will gladly take over an outdated woodpecker gap as shelter, additionally they construct these leafy dreys as each summer time and winter houses. Twigs, typically gnawed from a tree when the leaves are nonetheless intact, type the framework upon which layers of extra leaves are stacked, woven and stuffed.
The summer time drey is flatter, lighter and extra open, holding it ethereal within the heat months. Some squirrel nests you see in winter might look a bit haphazard and falling aside, which could possibly be a summer time nest—or it could possibly be an imposter altogether. Squirrels typically construct phony nests as a means of tricking predators and diverting consideration away from their actual houses. Winter dreys seem far sturdier. The thick walls of overlapping natural materials keep wind, water and snow from penetrating the interior, whereas pockets of air present insulation that maintain chilly out and warmth in.
Squirrels rely closely on these houses in winter to stave off freezing temperatures, particularly when the thermometer plunges at evening. Generally two or extra squirrels cozy up collectively, their collective physique warmth warming the nest inside to temperatures far past that of the surface. Analysis has proven the within of an occupied drey will be an astonishing 60 to 85 levels Fahrenheit hotter than the ambient temperature, making a one-of-a-kind squirrel sauna.
I like to consider these nests which can be revealed in winter as little gems of nature, sparking curiosity concerning the lives of animals in Lake County and past. And as we rejoice the 10-year milestone (!) of the Lake County Nature blog this January, I’m hopeful that by means of the years, it too has uncovered nuggets of nature that ignite surprise for our readers, and that it’s supplied inspiration to discover the pure world in a deep and significant means.