Sunday, September 9, 2007

"Silence of the Songbirds"

Bridget J. M. Stutchbury is professor of biology at York University and author of Silence of the Songbirds: How We Are Losing the World's Songbirds and What We Can Do to Save Them.

She applied the Page 69 Test to the book and reported the following:
“Given the large amount of forest loss in the tropics, it is probably true that most hooded warblers heading south for the first time will find themselves in a hot, dry patch of scrub looking at cattle all winter rather than flitting among the branches of a towering mahogany tree while jaguars pass by below them.”

This passage on p. 69 of Silence of the Songbirds captures the essence of how humans have drastically altered the natural world, and why we should care. Most of “our” songbirds in North America do not spend the winter here, but instead head south to tropical countries as they have done for thousands of years. Massive human population growth in Central and South America in the past few centuries has robbed “our” birds of their safe winter homes. Bird watching is one of the most popular past-times in North America, and we spend billions of dollars on it, but we cannot take for granted that our songbirds will return in the spring. We all need to think more globally in terms our impact on the nature and migratory songbirds help us to make this connection. “Not in my backyard” suddenly takes on a different meaning since we all share the same giant backyard.

How do we know that migratory birds suffer when they no longer have thriving forests to live in? Silence of the Songbirds explains the research that I, and my colleagues, have done over the years on migratory birds. I make the science easy to understand and fun to read (well, most of the time!). One passage on p. 69 describes a study that my Ph.D. student Francisco de los Santos did in Mexico and Belize:

Next, Francisco asked the birds which habitat was best for them…. He measured levels of the hormone corticosterone, which is an indicator of chronic stress. Birds will become stressed out if they are chronically short of food, living under the constant threat predation, or frequently chased and harassed by other birds….. Parents of young children and people who commute in heavy traffic every day have high levels of corticosterone, while retirees who spend their time on photography and golf likely have low levels…. The birds living in the scrubby field edges in Mexico had very high stress levels, a result of the daily challenges of finding food and staying alive in a poor habitat.

The serious decline of migratory songbirds is not merely an opinion or a gut feeling, but a fact easily seen in the careful and long term studies carried out by volunteers and professional scientists. The weight of evidence for the extent and cause of songbird declines is overwhelming, and will spur readers into action by buying shade grown coffee, recycled paper products, and crops that are relatively bird-friendly in their pesticide use.
Read an excerpt from Silence of the Songbirds and learn more about the book and its author at the official website.

Visit the complete list of books in the Page 69 Test Series.

--Marshal Zeringue