By Bridget Stutchbury. HarperCollinsCanada, 256 pp, $32.95, hardcover

The Pope kills warblers. Okay, this is my conclusion, not that of Ontario-based naturalist Bridget Stutchbury. And it's not like Joe Ratzinger is traipsing around the Guatemalan jungle with a mist net and a bottle of chloroform, picking off buntings one by one. Being inherently more diplomatic than I, Stutchbury puts it this way: "Latin America and the Caribbean currently are home to an incredible 560 million people, and this is projected to climb to 710 million by 2030. These extra 150 million people will need homes, food, and a livelihood, so we can expect that tropical deforestation will carry on like a runaway train until the primary forest is all but gone."

And when that happens, Stutchbury contends, the birds of North America will be in big trouble–at least those that migrate every year to winter homes in southern forests. These birds, by the way, aren't just pretty little things; they keep our woodlands healthy by feeding on insects and dispersing the seeds of maple, pine, and oak trees. By forbidding the use of birth control and other family-planning strategies, the Catholic Church has ensured that the human population of South and Central America will continue to grow, with the result being many avian extinctions.

Of course, the Pope's not the only one with songbird blood on his hands. Probably the worst offenders are the pesticide companies, which continue to sell products that have been banned in North America to Third World farmers: not only are they killing birds, they're poisoning peasants. But we're all guilty: every time we quaff a cup of diner java or peel a factory-farmed banana, we're helping to raze another acre of rain forest.

Granted, we can change. Stutchbury suggests that we drink only shade-grown coffee from plantations that mimic old-growth-forest habitat; that we eat organic produce; and that we be more careful when choosing the paper products we buy.

Will these measures be enough to save the wood thrush, the ovenbird, and the bobolink? Frankly, the prospect does not look good. Still, we must try.