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When much of Michigan's vast forests fell to the ax and saw in the late 1800s, many woodland bird species declined. These included the common raven, wood thrush, ovenbird, American redstart, whip-poor-will, scarlet tanager, and cerulean and hooded warblers. Wild turkeys were extirpated and passenger pigeons became extinct in Michigan, although this was also due to commercial overhunting. Hairy and pileated woodpeckers were also impacted along with great-horned, northern saw-wet, and barred owls. Today, wild turkeys have been reestablished and many species of songbirds are doing well in Michigan's forests. However, migratory species are declining at an alarming rate. From an overall landscape perspective, many woodland birds survive best in large tracts of forests connected to each other by forested corridors. Therefore, there are many management opportunities for woodland birds in northern Michigan, which is currently more than 70 percent forested. Options within southern Michigan exist in forest areas, and riparian zones. Neighbors who cooperatively manage their woodlands also increase opportunities for woodland bird management. Small forested tracts are also very important for some species like the northern cardinal and the great-crested flycatcher. Migrating birds may also use these small forests as stop over sites. Forest TypesMichigan is home to many types of woodlands, each of which attracts certain kinds of birds. Therefore, the first step to managing for woodland birds is to determine what type of forest system is dominant on your property and surrounding lands. Certain woodland birds are found in only one forest type. Requiring a certain element within the forest, these birds are considered habitat specialists. For example, red-winged crossbills almost exclusively feed on seeds from conifer cones within dry mesic conifer forests. Another example of a specialist species is the Kirtland's warbler. Their survival depends on jack pine stands that are eight to 20 years old. On the other hand, some species require a mix of forest types and different ages. For example, the indigo bunting does not require one specific forest type, but rather a mix of forest types to survive. They are located in brushy and weedy habitat along the edges of non-specific deciduous forests, swamps, abandoned farm land, roads, and railways. They prefer the fruits of shrubs, small trees, and vines. Edge-sensitivityFragmentation occurs when roads, homes, trails, power lines, and other forms of development break up the natural wooded habitat. Some birds are greatly affected by human disturbance to their habitat, while others are less bothered or not impacted at all. Edge-sensitive species are those birds with the lowest tolerance for fragmented habitat. Many of these birds seek forest interiors and shun forest edges. Species with moderate to high sensitivity to fragmentation do best at least 100 yards from the edge. Many habitat types create an edge next to woodlands such as grasslands, brushlands, wetlands, and river corridors. Edge-sensitive species prefer forest areas hundreds to thousands of acres in size. These large tracts of forest lessen problems such as nest predation and brood parasitism which is quickly increasing due to the rise in habitat fragmentation. One of the most common brood parasites is the brown headed cowbird, which is attracted to the forest edge. Cowbirds do not make their own nests, instead they invade the nests of others. Cowbirds remove host eggs before laying one of their own in the hosts nest. Their eggs tend to hatch one to three days earlier than the hosts. Because cowbird nestlings are larger and grow faster than the young of their host, the young cowbird receives more food and parental care than the hosts young. As a result, most of the hosts young do not survive. A female cowbird can lay up to 77 eggs each season if she can find enough host nests in which to deposit them. Woodland birds that are edge-sensitive include the broad-winged hawk, pileated woodpecker, wood thrush, yellow-throated vireo, ovenbird, American redstart, veery, and black-and-white, cerulean, and hooded warblers. Many edge-sensitive species are declining in populations as their habitat becomes more fragmented. Woodland birds with a moderate sensitivity to habitat fragmentation, which can tolerate stands between 40 and 100 acres in size, include the yellow-billed and black-billed cuckoo, hairy woodpecker, acadian flycatcher, scarlet tanager, red-eyed vireo, northern parula, white-breasted nuthatch, tufted titmouse, and blue-gray gnatcatcher. Woodland birds that are the most tolerant to an abundance of edge include the indigo bunting, gray catbird, Carolina and house wren, American robin, black-capped chickadee, northern cardinal, rose-breasted grosbeak, rufous-sided towhee, common grackle, northern oriole, brown-headed cowbird (a nest parasite), eastern wood-pewee, great-crested flycatcher, and downy, red-headed, and red-bellied woodpeckers. It is not surprising that many of these species are found in urban areas. Management ConsiderationsThe following are options to consider when managing for woodland birds. Edge-sensitive considerations:
Edge-tolerant considerations:
General considerations:
As you can see, even doing nothing to your wooded property will encourage some kinds of birds and discourage others. Specific management prescriptions will have a similar effect. For these reasons, it is important to classify the type of woodland habitat you own as well as properties adjacent to yours. You can then develop goals for the kinds of birds you want to encourage on your land. Forming a landowners association with your neighbors is a good way to enhance a larger forested area than your own property. Applying legal restrictions such as a conservation easement to your land is also a good way to eliminate the threat of future development. For information, contact the Michigan United Conservation Clubs.
Last Revised: December 12, 1999 |
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