David Burg of Wild Metro looks for an American woodcock (Fred Mogul/WNYC)

NEW YORK, NY April 02, 2007 —Hawks in Central Park. Beavers in the Bronx River. Seals under the Verrazanno. Thanks to cleaner water and fewer pollutants, many animal species either are appearing in the region for the first time or returning after a long absence. But local wildlife is also facing challenges, especially from climate change and development. As part of WNYC’s on how the metropolitan region is affected by climate change, reporter Fred Mogul takes a look at how the area’s ecosystem is adapting to change.

Part of Feeling The Heat, a climate change series

REPORTER: When you go looking for wildlife, you never know what you’re going to find. But some things are surer bets than others.

BURG: There’s the owl, see it, though the trees?

REPORTER: The owl chick is nesting in the crook of a tree. It doesn’t know how to fly yet and isn’t going anywhere anytime soon. But we’re trying not to scare away its skittish guardians. David Burg, founder and head of WildMetro, sets up a telescope about 150 yards away.

BURG: The chick is all fluffy white like a big snowball. Those are the down feathers that are pretty waterproof and very insulating like goose down jackets, so the reason a bird doesn’t stay downy like this is it’s not very aerodynamic.

REPORTER: We’re not in remote woods, though it feels like that. We’re in the northeast Bronx, in Pelham Bay Park. The forest gently slopes down to reeds, rocks and water, and from this spot you see the woods of southern Westchester and North Shore Long Island in the distance, but none of the city’s skyscrapers, factories or roadways. A similar outing more than a decade ago led Burg’s friends Michael Crewdson and Margaret Mittelbach to write a book titled “Wild New York,” about Five-Borough wildlife.

MITTELBACH: Seeing an owl in the Bronx is not something most people would expect would be possible. And what’s also neat is the owl’s in a patch of remnant forest, but we’re also by a salt marsh on the Long Island Sound, so it’s kind of two ecosystems existing side by side.

REPORTER: The owls have been well ensconced here in recent years -- after disappearing for what was probably a century or two – but they might not always be such a dependable presence. Pelham Bay Park is one of many local shoreline areas that naturalists are concerned about. Different studies project water levels rising 6 to 12 inches over the next 50 years due to global warming. That would flood marshlands and encroach on rare, old-growth hardwood forests like this one.

BURG: Is it tall enough that some of the trees will survive on top? Some people predict with a warming climate, there’ll be more violent storms. Probably some sort of forest will persist, it’s just when you shrink it, the amount of things that can call it home will also shrink.

REPORTER: Unlike many northeastern forests, this one-time wooded estate was never clear-cut for farmland in the 17th, 18th and 19th centuries. And while it also survived 20th century urban- and suburbanization, Pelham Bay Park, like many metropolitan habitats, is relatively small and hemmed in. That leaves little room to adapt to dramatic climate change. Michael Klemens, director of the Metropolitan Conservation Alliance, says that with global warming . . .

KLEMENS: . . .animals that are more adapted to cool temperatures probably are going to want to move up a mountainside. Well, if there’s roads and houses in between the bottom of the mountain and the top, the animals can’t get there.

REPORTER: Klemens says people and governments sort of understand that wetlands need protecting. But they under-estimate how much space other animals really need. Amphibians like frogs and salamanders breed in the water, but live on dry land to differing degrees.

KLEMENS: We tend to protect wetlands with a little bit of land around them, and these animals need a lot more land. The amphibians that are mostly highly aquatic species such as bullfrogs are those that are surviving cause those don’t have large forest habitat requirements. The wood frogs, the large beautifully colored mole salamanders – these are the species that travel 750 feet if not more from their breeding pools, and these are the ones being most impacted.

REPORTER: Getting people to care about frogs and salamanders can be a challenge, Klemens says. But there are more of them in total volume per acre in northeastern forests than the deer and larger mammals that capture people’s imagination.

KLEMENS: I can’t tell you whether having one species more or less of a salamander will make a difference, or one type of frog more or less, but ultimately, in sum total an impoverished ecological system will impact our ability to survive as a species. People have explained it almost like each species being a rivet on an airplane, and you can start pulling rivets out, and the whole thing will fall apart and come down.

REPORTER: Warming temperatures are already altering the mix of flora and fauna up and down the food chain locally and regionally. Many of the state’s apple varieties are decreasing in both quantity and quality, according to Horticulture Professor David Wolfe from Cornell. Winters are getting warmer, and many types of apple need a good couple months below 45 degrees to be at the top of their game in the spring.

WOLFE: We should be able to continue growing apples here, but there could be some quality problems or some yield problems with the varieties being grown, and farmers may gradually have to begin experimenting with different varieties and with different tree fruit species in order to stay in business over the long term.

REPORTER: Farmers are used to adapting and improving what they grow to changing conditions. This could mean not only higher temperatures but new pests and weeds. Take the threat of kudzu. The southern “mile-a-minute weed” has been gradually pushing north and now can be found in Pennsylvania.

WOLFE: It will literally grow right over abandoned automobiles and up poles and around parked buses. It does need fairly warm winter temperatures to survive the winters, and that’s what’s really changing in our area more than anything else, so it really gives the opening for kudzu and other species to make it up here. That’s the one thing that really limits there range right now is the low temperatures we get.

REPORTER: Back at Pelham Bay Park, warming trends have already helped non-native invasive species like the white poplar get a foothold. You might not even notice the spreading stands of these skinny trees, as you walked by. But what difference does a few more poplars make? WildMetro’s David Burg says it’s not just a question of personal preference . . .

BURG: They’re a handsome tree, but if you let these things go, they replace what was once a complex ecosystem, and it’s not like the native systems, where things co-evolve, so you could have a lot of complexity. Is complexity always good? I don’t know. They say the first rule of intelligent tinkering is to save all the parts, you never know if there is some kind of practical reason. Allowing it to be destroyed would be like allowing a fire to burn in Metropolitan Museum.

REPORTER: Burg and others say the presence of owls, beavers, falcons and seals in the city and region is a testament to the resiliency of nature and the power of human intervention. On the other hand, herons, egrets and several other species were making a comeback in the area, and now their numbers are declining. In the future, whether biodiversity grows or shrinks locally will be influenced not only by what happens nearby, but by changes in the atmosphere around the globe.

Links

Metropolitan Wildlife Alliance
Wild Metro