New modeling tool targets species distribution

When invasive species comes up in conversations on rangeland management, distribution and planning are of top concern for managers. As part of Hawaii Gov. David Ige’s (D) initiative, Biosecurity and Invasive Species, the Western Governors’ Association (WGA) hosted a May 1 webinar titled, “Species Distribution Modeling and Scenario Planning.” 

“Invasive species are an issue that we deal with every day, but using rational science and sound techniques to understand the risks we are facing are vitally important to spread the thin dollars even further,” Bill Whitacre, a policy advisor at WGA, explained. “There is an abundance of good work being done by states and their federal partners across the West.”

Terri Hogan, invasive plant program lead of the National Park Service (NPS), and Catherine Jarnevich, research ecologist at the U.S. Geological Survey’s (USGS) Fort Collins Science Center, summarized a new tool in development to visualize distribution models and inform decision-making efforts across the West in particular. 

“This work is important because it will provide a tool to invest in invasive species plant management efforts,” Hogan said. “As we all know, invasive species pose a threat to public and private lands, including natural resources and facilities within NPS.” 

She continued, “Land managers need tools about where to focus limited resources and make informed decisions on the effective management of resources.” 

NPS has worked in close collaboration with USGS on the project throughout the process of developing the tool, a list of invasive species of concern and an online tool.

“We are broadening our effort through work with the land management community as well,” Hogan said. 

Distribution models

Jarnevich explained NPS and USGS considered the ability to make a regional risk assessment utilizing distribution modeling.

In additional to risk assessments, Jarnevich noted the tool can be used to determine watch lists for potential species and in identifying potential habitat for invasive species. 

“It can also be used at the local level to target management efforts, such as within a park unit,” she said. “This model can also identify target areas where we might find invasive species or target satellite populations to control invasions more.”

In Wyoming, for example, distribution modeling was used in a post-fire area to identify cheatgrass infestation. 

Model development

Aggregated location data, primarily from the biodiversity information serving our nation (BISON) database at USGS and data from EDDMaps. 

“We use aggregated data, along with various prediction models on where species are found in the landscape,” Jarnevich said. “We feed this data into the model and a series of algorithms to make maps that provide predictions across the landscape.” 

Using a national library of nearly 60 different predictors, USGS and NPS are able to identify the subset of predictors the specifically impacts each species and its distribution.

Predicators include soil type, climate data, geography and more, including anthropogenic influences. 

Using the model

Today, an online tool called INHABIT – the Invasive Species Habitat Tool – is being used to deliver the model to managers.

“It is compatible across device types, meaning managers can use it in the office on their desktop computer, but they can also utilize it on their tablet in the field,” Jarnevich said. “We’re also seeking input from land managers that utilize the tool to continue to improve its usability.” 

The models allow managers to graphically see the potential for invasive species spread. It also allows users to allow more or less conservative predictions. 

“Depending on what we are using the model for, we may want to be more conservative,” she explained. “For example, if we’re doing a risk assessment, we may want to be more conservative, but if we’re sending a field crew out to control something, we may want more certainty on specific locations.” 

Other tabs

Additionally, with each species, predictor variables are provided in a separate tab to show the influence of each of the variables on the plant being considered.

“We also provide information in a data summary,” Jarnevich said. “In this tab, we can select a species and then a list of national parks, along with suitable habitat, known presences and more information.” 

She continued, “We’re hoping this information can be useful in risk assessments.” 

NPS and USGS also have a feedback tab that provides the opportunity for user feedback on potential new developments and features that are already in place. 

Moving forward

As NPS and USGS move forward, Jarnevich explained plans to work with partners and continue to grow and develop the tool.

“We want to know how land managers are using the tool for planning and in the field, as well as if there are differences in established versus new invaders and regional versus local assessments,” Jarnevich said. 

They also want to know what users would like to be downloadable, and if other features would be helpful, including future priority species. 

“We have 40 species we will be adding to the system this year, and in the next year, we hope to create models for at least 50 more species,” she said. “We also want to know more about what people need for tools to be successful.”

Jarnevich emphasized, “We’re really interested in seeing how we can continue to improve this tool as we move forward.” 

The project was funded by several USGS programs, the U.S. Fish and Wildlife Service and the U.S. Park Service. 

Saige Albert is managing editor of the Wyoming Livestock Roundup. Send comments on this article to roundup@wylr.net.