Richard Conniff: Wildlife in an Urbanized World

Yale360:

we know almost nothing about what ecologist Meredith Holgerson at Portland State University calls “these cryptic changes happening” as humans occupy and alter a landscape. For her doctoral research at Yale University, she looked at the effects of suburbanization on wood frogs in 18 ponds in the prosperous Connecticut suburb of Madison. The area around the ponds had developed largely with two-acre zoning, allowing for survival of “pretty good red maple swamps and vernal ponds,” says David Skelly, a professor of ecology at the Yale School of Forestry & Environmental Studies who oversaw the research. But chemical analysis of the ponds demonstrated that, along with other changes, the wood frog larvae were getting as much as 70 percent of their nutrients from materials leaching out of septic systems. “It suggests,” says Holgerson, “that tadpoles and other pond organisms are made up of human waste.”

The consequences of that remain unknown. But it also suggests that we may change the entire nutrient flow of an ecosystem, cause eutrophication, or introduce hormone-disrupting drugs or other chemicals in our waste — and still imagine that we live in a relatively intact habitat.

A City is an Ecosystem

Courtney Humphries, reporting for the Boston Globe:

Cities may strike us as the opposite of “the environment”: As we pave streets and erect buildings, nature comes to feel like the thing you find somewhere else. But scientists working in the growing field of urban ecology argue that we’re missing something. A city’s soil collects pollutants, but it also supports a vast system of microscopic life. Water courses beneath roads and buildings, often in long-buried streams and constructed pipes. And city ecosystems aren’t static; they change over time as populations grow, infrastructure ages, and different political structures and social values shape them.

Seen this way, the city is a distinct form of “environment,” and an important one. Truly understanding how it works—and how it affects the millions of people who may live and work there—will mean studying the whole city as a living system, both its organisms and its pipes, roads, and landfills. As cities grow, maintaining clean air and water in a place like Boston may depend on how well urban areas support trees, plants, and microbes.

Many of the truths that we cling to depend on our point of view. Truly wonderful the ecology of a city is.”