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Bird monitoring at Arkansas Post National Memorial: 105 species in 11 years
Of the birds that breed at Arkansas Post National Memorial, 42% are in decline across the Mississippi Alluvial Valley, yet the park's own bird community is faring as well as or slightly better than the region's, according to the Park Service. The National Park Service's Heartland Inventory and Monitoring Network has surveyed the park's birds during the breeding season since 2007, and this page summarizes its report through 2019.
The Red-headed Woodpecker lives at the park year-round and is a species of conservation concern in the region. NPS photo.
Why birds are counted
Birds eat pests, disperse seeds and pollinate plants, and the Park Service calls them indicators of environmental change, a canary in the coal mine for an ecosystem. Flood control and deforestation for agriculture threaten bird habitat around the park. Some species, among them the Common Grackle, Common Yellowthroat and Northern Bobwhite, are declining at alarming rates in the region. The network's scientists survey birds in the breeding season and record the structure and makeup of the plant communities they live in, then compare park trends with regional ones.
What the surveys found
Over 11 years of surveys (none were done in 2008 and 2009), scientists found 105 bird species, an average of 43 a year. Ninety-three of them could breed in the park, about 91% of the species reasonably expected to breed there. Eight breeding species are of conservation concern in the Mississippi Alluvial Valley region:
| Species | Status at the park |
|---|---|
| Bald Eagle | Year-round resident |
| Red-headed Woodpecker | Year-round resident |
| Dickcissel | Summer resident |
| Kentucky Warbler | Summer resident |
| Least Bittern | Summer resident |
| Orchard Oriole | Summer resident |
| Prothonotary Warbler | Summer resident |
| Wood Thrush | Summer resident |
The Prothonotary Warbler population at the park has increased since 2007. It lives in the park's riparian (streamside) woodlands. NPS photo.
Habitat and trends
The park lies in the forested floodplains of the Mississippi Delta. The region once held the greatest bottomland hardwood forest on Earth and was subject to massive annual floods, but since European settlement less than 25% of the forest remains and flooding has fallen by about 90%. The number of bird species at the park rose from 2007 to 2019, which the Service takes to suggest that its habitat has improved. The region is one of 67 identified in the North American Bird Conservation Initiative, and the park lies at its center.
The Mississippi Alluvial Valley Bird Conservation Region, with the park at its center. NPS image.
Eighteen species were common enough for scientists to measure their abundance:
- Thirteen increased significantly since 2007: Acadian Flycatcher, Blue-gray Gnatcatcher, Blue Jay, Brown-headed Cowbird, Carolina Wren, Eastern Wood-pewee, Great Crested Flycatcher, Mourning Dove, Northern Cardinal, Prothonotary Warbler, Red-bellied Woodpecker, Tufted Titmouse and Yellow-billed Cuckoo.
- Three held steady: Indigo Bunting, Pileated Woodpecker and Summer Tanager.
- One decreased significantly: Red-winged Blackbird.
- No trend could be set for the Canada Goose, which went unobserved in five of the 11 survey years.
A comeback
Bald Eagles were absent from Arkansas from the mid-1950s to the early 1980s, and they nest in the state again. A pair nests at the park and has raised numerous young there in recent years, and eagles can be seen year-round.
A Bald Eagle at the park. NPS photo.
Sources
- National Park Service, Arkansas Post National Memorial, "Bird Community Monitoring at Arkansas Post National Memorial, 2019" (https://www.nps.gov/articles/arpo_birdmon.htm), a Heartland Inventory and Monitoring Network summary; rewritten in hubnx's own words.