Originally published by The Young Forest Project
By: Charles Fergus, Wildlife Management Institute
Working the Edges
"We're mostly managing forest edges and fields here in the St. Lawrence Valley," says Andrew Hinickle, a biologist for Audubon New York, the state program of the National Audubon Society. Those management efforts create more breeding and feeding habitat for golden-winged warblers, along with dozens of other kinds of wildlife that use the same type of cover as those beleaguered songbirds. "We’re not generally going into the woods and making clearings," Hinickle continues. "It’s more about maintaining and improving on what's already here."
The St. Lawrence Valley is in upstate New York near the Canadian border. Much of the young forest in the valley grows on farmland that was abandoned decades ago and is gradually coming back in shrubs and small trees. "The valley has shallow soils over bedrock of the Canadian Shield," Hinickle notes. "Those conditions keep forests in a young growth stage longer than in some other places."
The valley is part of the Great Lakes Focus Area identified by scientists in the Golden-Winged Warbler Working Group. The focus area stretches from northern New York west to Minnesota and Manitoba and supports around 95 percent of the species' global breeding population, or 392,000 out of 414,000 individual golden-winged warblers in North America, according to 2010 estimates. (The warbler's breeding range also extends south into the Appalachian Mountains.) The Working Group's goal is to boost the Great Lakes Focus Area population to 441,000 golden-wings by 2020.
The golden-winged warbler has suffered one of the steepest population declines of any North American songbird over the past 45 years. The warblers breed in North America during summer, then migrate to a wintering range that extends from Guatemala, in Central America, to Colombia, in South America. Habitat preservation on both summer and winter ranges is crucial, and the St. Lawrence Valley is a key locale.
"Golden-wings are picky about their habitat," Hinickle says. "The vegetation needs to have a certain structure, both vertically and horizontally. Golden-wings want 10 to 30 percent canopy cover" (in which the leafy canopies of trees cover 10 to 30 percent of a given area) "that includes a change in structure every few feet. They want herbaceous cover" (grasses, sedges, and wildflowers such as goldenrods and asters) "in among the patches of shrubs. The shrubby habitat needs to be tucked up next to some mature forest, where adult birds can take their young after they leave the nest. The mature forest needs to be at least 70 percent deciduous trees," as opposed to coniferous, or evergreen, trees. And in the general area, "The overall landscape needs to be 50 to 60 percent forested."
Upper and Lower Lakes Wildlife Management Area
Upper and Lower Lakes WMA lies 6 miles west of the town of Canton. The New York State Department of Environmental Conservation manages the 8,757-acre area. In 2013, conservation partners began creating and improving habitat for golden-wings on 156 acres scattered among 23 management units on old farmland along the WMA's northern and southern borders.
Old fields ranging in size from 2 to 15 acres dot the units. Until recently, they were kept in grass through annual mowing. "The plan is to let those fields grow up in shrubs by ceasing mowing operations," says Hinickle. "The habitat will become a mix of cool-season grasses and sedges, weeds and wildflowers, along with blackberry, willows, dogwoods, and birches." On some sites, workers will plant shrub and tree seedlings to speed up development of the desired habitat structure and to boost biodiversity.
As shrubs and woody plants spread, workers will brush-hog around the edges of shrub clumps to keep them from merging with one another and creating a shrub monoculture. (Remember, golden-wings need low plants carpeting the ground between the shrub islands.)
Conservationists are working to suppress invasive alien shrubs, such as buckthorn and Asian honeysuckle, to keep them from choking the habitat. "We knock the invasives back by manually cutting them and then applying herbicides to any regrowth," Hinickle says. He points out that the invasives' fruits aren't as nutritious or as long-lasting as those produced by native shrubs such as arrowwood and dogwood. "If songbirds eat large amounts of buckthorn berries, the fruits can have a laxative effect, which doesn't improve the birds' condition prior to migration."
Timber harvests – both commercial and non-commercial – are additional tools that the conservation partners are using. In the wake of cutting older trees next to shrubby fields on several management units at Upper and Lower Lakes, young aspen and birch trees now grow thickly. "Golden-winged warblers use these regrowing timber stands," says Hinickle, "as do ruffed grouse and American woodcock."
Hinickle adds: "For golden-wings, you want a feathered edge where the woodlands meet the old fields. It almost looks like stadium seating, going from low growth in the fields, up through the taller shrubs, to small trees along the edges of forest stands, and finally to the mature forest" that covers much of the surrounding landscape.
"We try to keep five to eight canopy trees per acre – trees with a diameter at breast height that's greater than 9 inches." Male golden-wings perch in the trees when they sing to attract mates and to defend their 2.5-to-5-acre individual breeding territories.
The goal is to end up with 10 to 40 percent of a given management unit covered with shrub clumps. "I call them 'shrumps,'" Hinickle says with a smile. "Basically, we're creating a mess – we want a certain randomness to the habitat. What we're doing is mimicking a natural disturbance, like an area of forest growing back after the trees have been removed by beaver flooding or a wildfire."
He adds, "It took me a short time to recognize good golden-wing habitat when I saw it, but about a year to understand why it was good habitat. There are a lot of nuances to creating such habitat. For instance, you need variety in the size of the perch trees – they shouldn't all be the same height. At Upper and Lower Great Lakes, our goal is to create a mosaic of varied habitats."
The demonstration area will boost golden-wing numbers in the St. Lawrence Valley. It will also offer human visitors a chance to see what the birds' habitat looks like and to observe the rare warblers as they go about breeding, nesting, and feeding, along with many other wild creatures that, not quite as picky as the golden-wings, will also thrive in the mix of low plants, shrubs, and regrowing woodland: wild turkeys, ruffed grouse, American woodcock, whip-poor-wills, cottontail rabbits, white-tailed deer, and a large suite of songbirds including eastern towhees, chestnut-sided warblers, willow and alder flycatchers, brown thrashers, and indigo buntings. Many of these animals are considered Species of Greatest Conservation Need in New York, since their numbers have been falling over the last 40 to 50 years as the amount of young forest habitat has dwindled in the state.
Audubon New York has also joined forces with a pair of nonprofit conservation organizations to create two more habitat demonstration areas in the St. Lawrence Valley.
Grand Lakes Reserve
At Indian River Lakes Conservancy's Grand Lakes Reserve, two management units totaling 8 acres are being transformed from decent golden-winged warbler habitat into excellent habitat. The site is 3.5 miles northeast of Redwood, NY. Thinning trees at the forest's edge, removing invasive shrubs, brush-hogging around shrub clumps to keep them from growing into one another, and cutting out evergreen trees are among the techniques that managers are using to bring the habitat into tip-top shape for golden-wings. The project is supported in part by a Land Trust Alliance grant. A hiking trail winds through the demonstration area, letting walkers study the intricacies of golden-winged warbler habitat and observe the varied wildlife that uses it.
Otter Creek Preserve
The Thousand Islands Land Trust's 105-acre Otter Creek Preserve is one-half mile south of Alexandria Bay, NY. There, three habitat management units take up 83 acres, with 21 acres undergoing active management for golden-winged warblers and the remaining 62 acres being managed as mature forest. The land trust is using a New York Parks grant to create a 1.9-mile hiking trail. A Land Trust Alliance grant helps pay to improve golden-wing habitat through encouraging native shrubs while suppressing invasive ones, removing conifers, and letting shrubs thrive in grassy areas.
Reaching Out to Landowners
In tandem with helping to create habitat demonstration areas, Audubon New York contacts private landowners in the St. Lawrence Valley. "Our approach is very grassroots," Hinickle says. "We use workshops and site visits to gauge and stimulate interest, and we give advice on how to create habitat based on Best Management Practices for Golden-Winged Warbler Habitats in the Great Lakes Region." (The publication, by the Golden-Winged Warbler Working Group, is available as a resource.)
Audubon New York also partners with the USDA Natural Resources Conservation Service, or NRCS, to smooth the way for landowners to get financial help for creating and refreshing habitat. Audubon's Linnea Rowse is stationed in NRCS's Watertown, NY, field office. "We help private landowners apply for financial assistance through NRCS's Environmental Quality Incentives Program," she says. EQIP funds management practices such as making patch cuts in forested areas, selective tree felling in old field settings, feathering edges of forests where they meet old fields, brush-cutting, and planting trees and shrubs.
Hinickle and Rowse hold workshops on the three St. Lawrence Valley demonstration areas. "We'll get 15 to 30 landowners to attend a workshop," Hinickle explains. "Some may be farmers, some will be hunters, and many are birders or folks enthusiastic about wildlife. We try to explain concepts of landscape change, and how natural disturbances once made enough habitat for golden-winged warblers, woodcock, grouse, and other wildlife – and how today we suppress those disturbance processes to the point that now we must actively make young forest for the wildlife."
He adds, "We also talk about how the St. Lawrence Valley is unique, and how it connects the Great Lakes and the Appalachian populations of golden-wings," whose ranges used to be joined but now are separate.
After a workshop, Hinickle and Rowse might receive invitations to visit 15 properties, and, as a result, five landowners might sign up for habitat projects. Over the last two years, seven landowners have received EQIP funding, with two pending and five in the application pool for 2016.
One such landowner is Nicole Caldwell, whose 65-acre Better Farm is a sustainability education center, artists' colony, and organic farm.
"Linnea did a site visit," Caldwell says, "and she found two breeding pairs of golden-winged warblers on the farm. She pointed out that we already had a significant amount of habitat to work with." On 7.7 acres, Caldwell has launched a variety of habitat improvement practices, including removing invasive shrubs (mainly honeysuckle), selective tree-felling to enhance the woods' feathered edge, and planting native shrubs such as silky and red dogwood, serviceberry, arrowwood, and hawthorns.
"I inherited this property from my uncle, who was an avid birdwatcher," Caldwell says. "When I heard about the program to help golden-winged warblers, I thought it was a perfect fit. Part of Better Farm's mission is to teach people about the local environment, and how having wildlife depends on sustaining a healthy habitat. We want Better Farm to be a living laboratory. We want to help wildlife while educating and inspiring people so that they take steps to help wildlife, too." (Nicole Caldwell has written about Better Farm's habitat work for golden-wings in her blog.)
"More landowners are signing up to improve their land for golden-wings each year," Hinickle says. "And that’s a good thing, because 80 to 85 percent of the land in New York is in private ownership. Getting landowners to make young forest is vitally important. The future of golden-wings, like so many other kinds of wildlife, depends on what private citizens are willing to do to preserve, create, and enhance their habitat."
Partners working together to create young forest in the St. Lawrence Valley include Audubon New York, New York State Department of Environmental Conservation, Clarkson University, Cornell University, USDA Natural Resources Conservation Service, Indian River Lakes Conservancy, and Thousand Islands Land Trust. Audubon New York actively creates young forest and shrubland habitat for birds and other wildlife.