Denali Road Closure Has Profound Effect

Those of you privileged to have visited Denali National Park, Alaska know that the Park has only one road through.  Roads have significant effects on wildlife.  Unlike other more visited parks like Yellowstone and Glacier, Denali has been managed to control the amount of vehicle access, substituting buses for private cars, leaving the road unpaved, and limiting the amount of traffic.  In 2021, a landslide at Pretty Rocks closed the western fifty miles of road completely, and while contractors build a bridge over the landslide, wildlife scientists are studying the effects of the unexpected closure on the park's wildlife,

Humans often convert animal trails into roads, but at Denali the reverse has occurred.  Animals like bears, wolves,  and caribou are using the open space as a trail for their wanderings.  Without roadkill, magpies and foxes are gone; like predators the absence of vehicles has produced a trophic cascade in the ecosystem.  At Wonder Lake, the western terminus of the road, the amount of waterfowl and wading birds along the causeway is astounding. Surely, the absence of road noise has affected these birds.   The last time there was an event similar to the road closure, was during the Pandemic, in the spring of 2020.  The disease kept humans in their homes; scientists humorously refer this period as the "Anthropause".  Roadkill plummeted, animals wandered farther, and it seemed the bird song was more pronounced if not sweeter.  When the humans came back, roadkill accelerated due to behavioral lag.  Animals accustomed to owning the road are were slow to readjust their behavior to human dominance once again

This latest return to wilderness paradise will not last forever.  The 475 ft bridge construction is costing more than $200 million, and is scheduled to open to the public in 2027.  How the animals will react to traffic once again is not clear. Although it is known that sow bears use the road as a human shield to protect their vulnerable offspring from aggressive boars who will kill them if given an opportunity. [photo credits: E. Mesner] The Park Service is gathering behavioral information during this quiet time.  Bears on ether side of the closure are monitored via GPS collars to study and compare their behavior and movements.  The closure, an inconvenience to the public, has proved to be a benefit to science. Hopefully the data will be used to determine the necessity of capacity caps at more visited National Parks in the lower 48.  Because roads kill.