An unseasonably warm breeze welcomes the sunset near the Occoquan River. In the distance, an osprey nest has been commandeered by a Great Horned Owl. His eyes are glowing as he stares ahead.
As dusk sets in, everything takes on an orange glow. And from every hole in the ground and fork in a tree, the park springs to life. A group of nature lovers called Friends of the Occoquan get together at this refuge a few times a year, at night, just to see the show. Larry Underwood, a retired biologist with Fairfax County Parks, says this is the best time of day and the best part of the year.
"A lot of animals are just active at this time," he says. "Some are active only at this time. And you're likely to get the night animals overlapping with the day animals, so you're going to see some of each."
Some of the animals visible at the river that evening include a muskrat, a snapping turtle, deer, and a bald eagle.
Don Moore, associate director for animal care at Smithsonian's National Zoo, says it's not surprising to see all these animals at dusk. He says you have to think of time as a niche in ecological terms.
"We know that spaces are niches," says Moore. "There's a temperate forest niche, there's a freshwater river niche, and animals have evolved to live in those different niches."
He says sound is also a niche.
"You know we've got a little bit of an arms race going on if you will, between the predators and the prey," he says. "So the owls have these very nicely designed ears so they can triangulate on the noise that's coming from the prey."
The warmth of the day still hangs in the air, but the sky has gone dark. All around from every angle, there's a steady din. Naturalist Rick Czarnowsky peers into the bushes with a spotlight and spots a tiny frog that looks like he's blowing bubble gum.
"That's his vocal sac," says Czarnowsky, referring to the frog's body part resembling bubble gum. "And you can see very faint there's an X on his back. That's a spring peeper."
He says it's surprising to see these tiny frogs still out, with the warm weather he had predicted we'd miss them. An owl hoots in the distance.
"I never get tired of hearing owls," says Czarnowsky. "The more I hear 'em, the more I wanna hear them. That's probably my favorite sound."
Sometimes, in order to go places, all you have to do is open your ears.
[Music: "Walkin' After Midnight" by Madeleine Peyroux from Dreamland]
Photos: Nature Refuge