Truly Great Lakes National Forests, Michigan’s Hiawatha and Huron-Manistee provide visitors a chance to explore several lakes, including the Great Lakes, and hundreds of miles of streams. Within these lake-filled forests, visitors can hike and swim, visit lighthouses, and spot diverse wildlife, including gray wolves, deer, monarch butterflies, bald eagles, and one of North America’s rarest songbirds, Kirtland’s warbler.
Our tree planting efforts
on these two National Forests contribute to the recovery of this rare
bird, a habitat specialist that requires young jack pine stands for breeding
and nesting. Since 2011, we’ve planted more Two Million jack pine seedlings
across nearly Two Thousand acres of public forest land.
After arriving from its winter grounds in the Bahamas in the spring, the warblers breed and nest in young jack pine forests of Hiawatha National Forest. They nest on sandy soil underneath young jack pines that are between 6 and 22 years old, 5 to 20 feet tall, and have enough space between them for adequate sunlight, yet dense with abundant foliage. Why such specificity? When the trees are about six years old, the lower branches are just long enough to reach near the ground and hide a nest underneath, while the sunlight keeps the foliage alive and fluffy. As the trees age, taller branches block sunlight to the lower branches, which then begin to die and can no longer conceal a nest.
The loss of suitable habitat prompted the Kirtland’s warbler to be one of the first species to be protected under the Endangered Species Act of 1973. Historically, fire played an important role in jack pine ecosystems. Fires cleared out thick brush and old trees and allowed the jack pine’s serotinous cones to release seeds and regenerate new stands of young jack pine, essential for Kirtland’s warblers. Decades of fire suppression has yielded dense older stands, inhibiting the establishment of young stands and restricting the warbler’s habitat. Habitat management and tree planting helps to imitate the effects of fire and create suitable habitat for the warbler.
While Kirtland’s warblers remain rare, these habitat specialists are on the rise and they were removed in 2019 from the federal list of endangered species. Their numbers have increased from about 200 pairs in the early 1970s to about 2,245 pairs in 2021 at their nesting grounds in northern Michigan, Wisconsin, and Canada.
Our efforts to improve Kirtland’s warbler habitat through tree planting have been supported by a diverse mix of individual, small business and corporate supporters. And in 2024, we are expanding our efforts through our partnership with the Huron-Manistee National Forest to include cone collection and capacity support. This will ensure the future of Kirtland’s warbler habitat and the forest’s jack pine seed stock, replenishing seeds lost to a 2017 windstorm at the seed orchard.
Help important habitat-building work like this with a donation to our Holistic Reforestation Fund!
Header photo: Andrew Baker