Nearly twice the size of Manhattan and occupying 53 square miles, Denver International Airport (DEN) is the largest US airport by land area. Located 20 miles northeast of downtown Denver, the airport is largely surrounded by shortgrass prairie. Home to iconic wildlife like the American Bison and Pronghorn, shortgrass prairie is one of the most threatened ecosystems in America. Nearly half of original Colorado prairie has been converted to other uses. Of the remaining prairie, the vast majority is privately owned. This has encouraged the protection and restoration of publicly owned land, including what has now become the Rocky Mountain Arsenal National Wildlife Refuge.
Situated just west of DEN, the Rocky Mountain Arsenal NWR encompasses 15,000 acres of restored shortgrass prairie. The refuge connects to the airport property on its eastern border through Peña Boulevard, the primary access to DEN. The highway runs west to refuge and skirts around its southeastern edge. Along this path, the city of Denver has plans to create what it calls a “Corridor of Opportunity and Airport City.” Development has begun and includes a new rail line and hotel, with plans to create housing and business infrastructure. However, the corridor is also well situated to connect prairie on the airport campus to the wildlife refuge.
A recent proposal explores potential development scenarios for the corridor and their impact on pollinator communities. The report evaluates two sets of possible developments: one prioritizes the airport city, and the other prioritizes pollinator habitat. Both sets consider plans using the current property and with an expanded boundary that increases the connection with the Arsenal Wildlife Refuge.
Of the airport’s 33,000 acres, the majority of land is prairie or agricultural, and only 10% is covered by built surfaces. DEN plans to expand its terminals and construct new runways, but a large focus of all potential development plans is restoration of prairie habitat. In pollinator-focused scenarios, development is closely clustered and located closer to the airport to allow large, better-connected patches of native prairie. Regardless of patch size, however, native plants and habitat quality are prioritized.
Using the InVEST Crop Pollination model developed by Lonsdorf et al., the authors of the proposal found that small, urban patches of habitat were not able to compensate for habitat losses from development. However, the model indicated that by converting lands north of DEN from agricultural to shortgrass prairie, a plan prioritizing development could promote pollinators better than a scenario with less development but that does not restore farmland.
The authors concluded that to maximize pollinator abundance and diversity, development for DEN must include large, restored patches of native prairie. Expanding the airport boundaries was highly recommended, as even under a higher development scenario pollinator abundance increased.
Pollinator habitat represents just one aspect of sustainable development of Denver International Airport. Through efforts to manage groundwater, carbon sequestration, and more, DEN is committed to preserving ecosystem services throughout the development process and into the future.
McDonald, A., Ni, C., Li, J., Gu, T. and Jin, X. Scenarios for Pollinator Habitat at Denver International Airport. 2018, April 17.
SASAKI. Denver’s Airport City. 2018, April 5.
Lonsdorf, E., Kremen, C., Ricketts, T., Winfree, R., Williams, N. and Greenleaf, S. 2009. Modelling pollination services across agricultural landscapes. Annals of Botany 103:1589-1600.