Get to know the fascinating dawn and dusk dwellers that thrive in the Potomac’s “twilight zone”
/When we’re just starting the day or winding down for the night, crepuscular critters are at their busiest.
A bobcat's evening hunt caught by NPS wildlife tracking cameras.
Fall is just around the corner, and while we love a brisk leaf-crunching hike as much as the next nature lover, it can be tough to say ‘so long’ to summer’s sun and fun. But if you think shorter days mean less time to spot wildlife around the Potomac each day, you’ll be pleased to learn that some of the Potomac region’s most beloved species are most active between sunset and sunrise!
Curious to know why some animals prefer living in the liminal spaces of the day, and which critters to keep an eye out for on your next dawn stroll or twilight hike? Let’s illuminate this fascinating – and, if you ask us, underappreciated – side of wildlife behavior!
What does “crepuscular” mean? Shedding some light on your new fave vocab word
You’re probably already familiar with the term nocturnal, referring to creatures that keep their active hours overnight. You may have even heard the term diurnal used to describe sleep-wake cycles centered around daytime schedules (like ours!). But when we think of fireflies lighting up our yards in the evening or being awoken by an early morning chorus of birds, we’re calling crepuscular events to mind – that is, animal activity that occurs in twilight.
Crepuscular critters that spend most of their active hours around dawn are said to be matutinal, while those who are most likely to be observed around dusk are called vespertine. And just like that one friend who manages to take a 5 a.m. run and go out dancing every Friday night, some bimodal species make the most of both sides of twilight.
Why do some animals orient their waking hours around sunrise and sunset? As it turns out, there are plenty of compelling reasons.
Some species’ crepuscular habits are a means of avoiding predators – and that applies to predators aiming to limit their competition, too. The dim light of early and late hours may make camouflaging easier. And saving up energy for dawn and dusk means avoiding the day’s peak heat and chill, an increasingly common phenomenon as climate change pushes average daytime temperatures higher.
Get to know your wild crepuscular neighbors
For many of us, before or after work may be our best bet for getting outside on a nature walk, paddle, or pedal sesh. So when it dawns on you that some of the Potomac region’s most beloved species are at their busiest during these in-between hours, you might get a little extra motivation to head outside!
Tap through each gallery to see which critters you might encounter on your next twilight excursion.
If you’re around the water, keep your eyes peeled for…
Which crepuscular wonders are in the air?
If you’re in the woods, try to spot…
While many critters have evolved to make the most of the hours around sunrise and sunset, human behaviors can impact their ability to thrive:
Morning and evening commutes lead to run-ins with wildlife whose habitats overlap with developed areas, like deer, foxes, rabbits, and raccoons.
Light pollution from our homes and businesses may interfere with migration patterns and hunting schedules.
Animals may even shift their hours of activity later into the night to avoid human interference, adding new pressures on delicate ecosystems.
But we can all take action to protect the Potomac’s dawn and dusk dwellers. In addition to driving with extra caution around sunrise and sunset or looking into your local Lights Out initiatives, join Potomac Conservancy in our efforts to preserve unbroken stretches of land and clean water, keeping the Potomac wild and twilight hours a safe haven for all of our astounding crepuscular critters.
