Controlled Burns Boost Songbird Populations
Year after year, scientists report falling numbers of songbirds in Virginia. One likely reason – changes in the places they like to feed, mate and nest. To provide them with more healthy habitat, the Nature Conservancy is doing something bold – burning large sections of an 18,000 acre forest in western Virginia.
It’s a drizzly day in May – just after sunrise – but the rain hasn’t kept the Nature Conservancy’s Laurel Schablein and Nikole Simmons from driving the winding mountainous roads of Bath County.
“We have 107 birding plots within this 18,000 acre project,” Schablein says. “We’re going to one of those plots to do our avian monitoring survey this morning.”
The idea is to count species and individuals in a 100-meter radius – to figure out whether controlled burns are making a difference. Historically, lightning strikes sparked blazes that cleared the forest floor of debris, making way for new trees and bushes – places favored by certain kinds of birds.
As we hike through the underbrush, Schablein explains the difference made by a single controlled burn.
“If you look on this side, this is a more dense forest where you can’t see very far, and that is one kind of forest we need, but then if you look over here you can see a ton of the sky. You see a shrub layer and a little bit of a mid layer, and some dead trees that are also important. Woodpeckers really like to forage in the dead trees, and then any cavity nesters like chickadee or some owl species,” she says.
Ornithologists are especially worried about golden-winged warblers. They have one of the smallest global populations of any songbird – and this part of Virginia is their stronghold.
“They weren’t ever really common, but their numbers were growing in the early 1900’s when settlers were coming in and making clearings and starting farmland,” says Schablein. “Then people started mowing up to the forest edge or converting their habitat into fields. They really need small trees adjacent to large forests, so that’s why since the 1960’s both cerulean and golden-winged warblers have experienced 50-70% population loss.”
When we get to the center of a designated plot, Schablein gets out her clipboard and pen, while Simmons positions her binoculars. She won’t actually see most of the birds she counts, but she will hear them
“If the birds are at the tops of the trees, or if they’re jumping around the leaf litter behind dense shrubs, you just wouldn’t see them all,” Schablein explains.
She clicks her stop watch and the work beings.
“Oven bird A, B, redstart, red-eyed vireo, peewee,” says Simmons. “Worm-eating warbler, red-eyed vireo B.”
Over a ten-minute period, she’ll identify 16 individuals and 14 species.
“They have different calls. They have different chit notes. They have different songs,” says Schablein. “One of the things that was really helpful for me, at least starting out, is neumonics to help you remember some of the things. So we have the chestnut-sided warbler says, ‘Pleased, pleased to meet ya’. Carolina wren I remember as Germany, Germany, Germany.”
And the Eastern towhee with some English advice.
“He says drink your tea,” Simmons recalls.
In the course of their work, Nikole Simmons and Laurel Schablein will encounter black bears, bobcats and coyotes. That’s always a thrill – but the real excitement comes in reviewing the medium and long-term data they’ve compiled.
“We’ve seen an increase in species since 2011,” Schablein says. “We’ve seen an increase in total number of individuals. We’ve seen an increase in diversity.”