Gatekeepers of transformation: private landowners evaluate invasives based on ecosystem services

Authors: RAJALA, KIANDRA - Virginia Tech; SORICE, MICHAEL - Virginia Tech; Toledo, David

Submitted to: Ecosphere
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/26/2021
Publication Date: 7/21/2021
Citation: Rajala, K., Sorice, M., Toledo, D.N. 2021. Gatekeepers of transformation: private landowners evaluate invasives based on ecosystem services. Ecosphere. 12(7). https://doi.org/10.1002/ecs2.3652.
DOI: https://doi.org/10.1002/ecs2.3652

Interpretive Summary: Invasive plants have come do occupy and dominate large regions of the globe. In working landscapes, private landowners can have a large impact on controling or eradicating an invasive species. Using the northern Great Plains of the United States as a case study, we examined private landowners’ role as gatekeepers for an invasive species. We surveyed landowners to understand how the impacts of an unnamed invasive grass affects their acceptance of that species. We also explored how landowners’ acceptance of the invasive grass affected their intention to control the species. Our results show that acceptability of a grass was a large driver of landowners’ management intentions. Our work also explored the links between potential ecological outcomes, ecosystem service tradeoffs, and how landowners intend to respond to changes. Working collaboratively with private landowners to control an invasive species or guide management towards co-existence is likely necessary to conserve desired biodiversity and ecosystem services from northern Great Plains grasslands.

Technical Abstract: Biological invasions are not new, yet the anthropogenic drivers of global change have produced unprecedented ecological novelty through the expansion of invasive species. Private landowners play an important role in determining the trajectory of ecological transformations driven by invasives. Using the northern Great Plains of the United States as a case study, we examined private landowners’ role as gatekeepers for an invasive species. We employed a factorial vignette survey experiment to understand how the impacts of an unnamed invasive grass modeled on Kentucky bluegrass (Poa pratensis L.) were related to landowners’ acceptance of the species. We also explored the relationship between landowners’ acceptance of the invasive grass and their intention to control the species. Each landowner evaluated multiple vignettes that randomly varied based on how a novel grass species expanding in rangelands would affect provisioning services (season of forage availability, forage quality, forage quantity), regulating services (floral resources for pollinators, water infiltration and availability), and supporting services (grassland bird diversity, grass diversity). Acceptability was a large driver of landowners’ management intentions, and the status of all seven services was related to acceptability. Reductions to any ecosystem service reduced the acceptability of the grass species; however, only increases in forage quality, forage quantity, and water regulation were related to increased acceptability of the invasive. Scenario modeling shows that landowners displayed greater sensitivity to losses in a suite of ecosystem services than to equivalent gains. Scenarios specific to ecosystem service tradeoffs and representing Kentucky bluegrass invasion indicate that ecological losses may need to be severe before individual landowners change their management practices to reduce or control the species. Engaging private landowners in collaborative management efforts, whether to control an invasive species or guide management towards co-existence, is likely necessary to conserve desired biodiversity and the flow of ecosystem services from northern Great Plains grasslands.