Public preferences for controlling upland invasive plants in state parks: Application of a choice model

Invasive plants can have ecological impacts and cause economic harm particularly when recreational opportunities are lost. While the value of nature-related tourism has been assessed, little is known about the effect of invasive plants on recreational choices. This study uses non-market valuation techniques for the first time to quantify the net benefit of managing invasive plants in upland areas. We surveyed 1436 Florida residents to determine their preferences for state parks using discrete choice experiment questions with various levels of invasive plants and other attributes that impact visitation. Results imply that residents would be willing to pay $5.41 per-visit to reduce the coverage of invasive plants, $3.72 to improve facilities, $3.73 to increase the diversity of native plant species, and $6.71 to increase the diversity of native animal species. Using score variables to capture interaction effects, demographic variables were found to influence the marginal willingness-to-pay for invasive species control by −$1.13 to +$0.97 per visit. Those who have taken action against or are more knowledgeable about invasive species were also found to influence a respondent's willingness to pay (+$2.47 and +$0.83, respectively). Respondents who consider invasive species to be beneficial (e.g., since many species were imported for their esthetics) would be willing to pay an additional $0.80 per visit to a park with increased coverage. Using annual attendance data from 115 Florida state parks, we calculated statewide willingness-to-pay to manage invasive plants in upland parks. Park users would be willing to spend $89.4 million annually to reduce the level of invasive plants in the parks, which provides a baseline for evaluating control programs. Since current levels of funding ($32 million annually) are insufficient to control invasive plants, additional management may be warranted.

Research highlights
► We evaluated state park visitors’ preferences for invasive plants and other features using discrete choice modeling.
► Willingness to pay (WTP) averages $5.41 per-visit to reduce invasive plants.
► WTP averages $3.72 to improve facilities; to increase native plant and animal species WTP is $3.73 and $6.71, respectively.
► Experience with and knowledge of invasive plants have a moderate, statistically-significant influence on willingness to pay.
► We estimate statewide WTP to manage invasive plants in upland parks to be $89.4 million annually.