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A summer tanager. NPS.
In fourteen years of surveys, Homestead National Historical Park in Nebraska has recorded 98 bird species, 81 of which may breed there — and the community has barely changed. That steadiness is the finding: in a region where several of the park's common birds are declining, the park's own populations are holding, and one is growing.
Why count birds
Birds eat pests, spread seeds, pollinate plants and feed people; watching them is a multi-billion-dollar pastime, and park programmes lean on them. They are also early warnings: like the canary in the coal mine, a change in birds shows a change in the ecosystem before much else does. About 15 percent of the species that breed or may breed at Homestead are declining, some fast — among them the tree swallow, great-tailed grackle, loggerhead shrike and grasshopper sparrow.
Since 2009, scientists from the Park Service's Heartland Inventory and Monitoring Network have surveyed the park each breeding season, recording the birds and the structure of the plant communities they live in, and comparing the park's trends with the region's.
The habitat
Restored prairie and woodland at Homestead. NPS.
The park lies in the northeast of the Central Mixed Grass Prairie Bird Conservation Region, which runs from the shortgrass prairie in the west to tallgrass prairie and savanna in the east. Much of the middle of the region is farmland now, though large areas of good grassland remain. Homestead itself is mostly woodland and restored prairie, and about 130 breeding bird species live in the mixed-grass prairie in and around it.
What the numbers show (2009–2022)
| Result | |
|---|---|
| Species recorded | 98, of which 81 may breed in the park |
| Change over the years | little — in the number of species and in how they spread across the park |
| Most abundant and widespread | dickcissel, red-winged blackbird, house wren, common yellowthroat |
| Common enough to track | 18 species |
| Rising in the park | red-winged blackbird (moderately); no clear trend for the other 17 |
| Rising in the region | gray catbird, yellow warbler |
| Falling in the region | brown-headed cowbird, common yellowthroat, mourning dove, northern bobwhite, ring-necked pheasant, red-winged blackbird |
| Regional species of concern breeding here | Bell's vireo, red-headed woodpecker |
The red-winged blackbird is the odd one out: declining across the region, increasing in the park.
The red-headed woodpecker
A red-headed woodpecker. NPS.
The red-headed woodpecker lives at Homestead all year, and is a species of concern for the region, declining across its range as its habitat and food disappear. It is one of four North American woodpeckers that store food, and the only one that covers its caches — insects, nuts and seeds wedged into trees — with wood or bark. It defends its territory fiercely, sometimes wrecking other birds' nests or removing their eggs. It needs mature trees and dead snags in woods and orchards for nesting and storing food, which is why keeping the park's woodland matters for it.
Sources
Written from "Bird Community Monitoring at Homestead National Historical Park in Nebraska, 2022", National Park Service Heartland Inventory and Monitoring Network, a work of the United States government in the public domain. The full report is on the NPS DataStore.
Licence : CC0 1.0 (domaine public) · Adapté de www.nps.gov
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