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National parks have a clear mission: to keep their resources unimpaired for future generations. Carrying it out can be less clear-cut. The wild turkey, a non-native game bird now well established in Great Basin National Park, is a case in point.
How they got here
In 2003 the Nevada Department of Wildlife released one hundred Merriam's turkeys outside the park, aiming to build a population that could be hunted and would give people more chances to hunt and watch wildlife. It worked: the turkeys multiplied and spread into the park, where hunting is illegal. The year before this article appeared, they began roosting in trees near the Lehman Caves Visitor Center, leaving droppings all over the lawns and paths. Staff were able to scare the birds off and clean up, but the episode raised the question of what turkeys do to the park's natural resources.
What turkeys might do
Turkeys are large birds. They eat almost anything but mostly plants and insects, and seldom take vertebrates. As they forage they scratch up the soil, and they could spread non-native plants such as cheatgrass and thistles. They can also set back restoration work by eating young, newly established plants.
Mountain lions, bobcats, coyotes, foxes and hawks all prey on turkeys, so more turkeys could mean more predators — and knock-on effects on those predators' other prey. Little in the scientific literature suggests turkeys will do harm, but research in the park itself — on their home ranges, diet, distribution and survival, and on their effects on natural resources — is warranted.
A problem no park can solve alone
The turkeys are a classic resource management dilemma. Wildlife ignores boundaries, and most parks are too small to manage whole populations on their own. Meeting the park's mission therefore takes cooperation among parks, neighbouring land managers, private landowners and wildlife agencies — as it does for bighorn sheep, Bonneville cutthroat trout, elk, rattlesnakes, bats and mountain lions.
The park could haze turkeys away from particular places, trap and remove them, or kill them. But without cooperation among its partners and active, science-based management, any of these would be only a short-term fix. As human effects on park resources keep growing, parks will more than ever need to work with partners and set priorities to meet the Park Service's mission.
Sources
- Bryan Hamilton, wildlife biologist, "Wild Turkeys Present Study in Wildlife Management," The Midden (Great Basin National Park), vol. 15, no. 1, summer 2015, National Park Service. https://www.nps.gov/articles/000/wild-turkeys-present-study-in-wildlife-management.htm
In queste pubblicazioniGreat Basin National Park
Licenza: CC0 1.0 (pubblico dominio) · Tratto da www.nps.gov
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