The calendar tells us that these are the first days of fall. But for wild creatures making their home in the city, the autumn shuffle is already under way.
They're moving along secret highways that parallel our own: the light-rail right of way, the JFX embankment, the banks of the city's streams, even the storm sewers.
Some are just passing through on their way to winter homes. Others, the young adults of the animal world, are leaving the family home and looking for places of their own. And although we rarely notice them, they're making use of every spare corner of the city.
There's a family of foxes in Druid Hill Park, says urban naturalist Bill Bridgeland. There are minks in the Jones Falls, opossums in the alleys behind downtown high-rises, and three small falcons living in Green Mount Cemetery.
The Baltimore Bird Club has tallied 210 bird species at Fort McHenry. Last winter, a birdwatcher spotted a ring-necked pheasant in Cherry Hill Park.
"People tend to think of the city as a wasteland," said University of Missouri ecology professor Charlie Nilon, a specialist in urban wildlife. "But there's actually a lot of wildlife habitat that usually goes unnoticed. You can find little havens right in the middle of the city if you look for them."
In Baltimore, ecologists are looking for those havens more than ever before. Ecologists traditionally have sought out remote jungles and mountainsides where conditions are supposedly "pristine." But there's a new recognition that those pristine places are rapidly giving way to cities and suburbs, where some plants and animals are not only surviving, but thriving.
"Sometimes places can look pretty beat but still have a lot of biological diversity and provide a lot of benefits," said ecologist Steward Pickett, the director of the Baltimore Ecosystem Study. The project, now in its fifth year, added Baltimore and Phoenix, Ariz., to a nationwide network of long-term environmental research sites funded by the National Science Foundation.
One of the scientists involved is Nilon, who is studying city birds along with colleague Paige Warren of Virginia Polytechnic Institute. One recent Saturday, he led an impromptu wildlife hike across the Morgan State University campus.
Just a few yards off Hillen Road, tucked between a tennis court, a cluster of dorms and the old brick ROTC hall, he found a promising spot: a quarter-acre patch of cattails behind a chain link fence. The scientists call it a storm-water retention pond, but most people would call it a gully, built to catch oil-slicked rainwater, soda cans and fast-food wrappers from a student parking lot.
Diversity in a ditch
Nilon, who grew up in Boulder, Colo., learned to love science in a place much like this - a trickle of water that his father called a stream.
"I think what it was was a drainage ditch," Nilon said. "It was pretty built up and developed and pretty much trashed," but it attracted turtles, frogs and birds. And it sparked his lifelong interest.
Someone planted the cattails in the Morgan State marsh, said Nilon, but young willows and mulberry trees have taken root on their own at the water's edge. Wild chicory, a European import, grows thickly on the steep slopes, its brilliant blue daisy-like flowers shooting straight up on three-foot stalks.
Within minutes, Forest Service biologist Richard Pouyat found a praying mantis in the tall grass, and wildlife ecologist David Curzon identified five kinds of late-summer butterflies, including a black-and-tawny swallowtail nearly the size of a man's hand and glittering clouds of tiny, electric blue Eastern tailed butterflies.
Birds, frogs, muskrats
"This really is butterfly heaven," said Curzon, who says Baltimore's plants and animals - and this year's soggy summer - remind him of his native London. "Any place like this that isn't sprayed [with pesticides] is really a little refuge."
By night, red-winged blackbirds roost in the cattails, and in spring the marsh is loud with frog songs, Nilon said. And he suspects that the muskrats living in nearby Herring Run travel through culverts and ditches to feed on the succulent marsh plants.
"What are y'all doing down there?" asked a young man walking with two friends on a nearby sidewalk.
"Looking for wildlife," chorused the ecologists. The trio on the sidewalk exchanged disbelieving looks. "Have you ever looked around down here?" one of the group asked them.
"No," said the young man. "It smells stinky."
The butterflies in the Morgan State marsh will die off in a few more weeks, said Curzon. Meanwhile, migrating birds and bats are urgently hunting for the last flowers and bugs of summer.
The ruby-throated hummingbird darting along the banks of Herring Run is bound across the Gulf of Mexico, a journey of more than 1,000 miles.
"They need to feed quite a lot every day, so it's a constant search for blossoms," said Curzon. "It's literally a matter of life or death."
Similarly, bats that spent the summer unseen in rowhouse attics are emerging now. Startled homeowners might see them clinging to doorways and window screens. It's a last hurrah as the bats gobble insects, building up fat reserves that will carry them through a winter's sleep in the caves and abandoned mines of Western Maryland, Bridgeland said.
A treacherous time
Bridgeland, a Northern Arizona University doctoral student, worked as an independent ecologist in Baltimore for 23 years, teaching at the Johns Hopkins University and relocating wild animals that strayed into homes or businesses. He said this is also the most treacherous time of year for creatures that live in the city year-round.
These animals - raccoons and opossums, muskrats and mink, and the occasional otter and beaver - must spread out to find new shelter and new sources of food.
"The young ones are leaving their parents for the first time, and there's a lot of inexperienced juveniles that get themselves in trouble," said Bridgeland. "There's a lot of mortality. Most of the animals that are born in a given year die by the end of that year."
City dwellers might see a turtle in a storm culvert, a raccoon picking through the underbrush along the light-rail right of way, or a groundhog burrowing into a highway embankment.
The wild creatures being seen now are in the midst of the autumn shuffle and are best left alone, Bridgeland said.
"It's pretty easy to coexist with them if we want to," he said. "After all, we are sharing the habitat with them, whether we know it or not."