MSU Graduate Investigates Presence of Monarch Butterflies and Other Pollinators in Roadside Habitats

Monarch butterfly on orange flower
Source: MS Word Image Library

Monarch butterflies (Danaus plexippus), the striking and iconic orange and black insects of postcards and motivational posters, have been in population decline since the 1980s and Thomas Meinzen, a master’s student in Montana State University’s Ecology Department, turned to a largely overlooked environment to save them. His thesis, Bees and Butterflies in Roadside Habitats: Identifying Patterns, Protecting Monarchs, and Informing Management, investigated the value of highway rights-of-way (ROWs) for pollinator, especially monarch, conservation. Supported by the Idaho Transportation Department (ITD), the project evaluated undeveloped land that parallels many roads for its potential to sustain western US monarch migrations and determined the variety of other pollinator species that used its native and non-native plants.

Thomas was advised by MSU Ecology Department Head, Dr. Diane Debinski, a butterfly specialist, in partnership with fellow ecology professor Dr. Laura Burkle, a bee specialist, and WTI’s Road Ecology Program Manager, Rob Ament. He surveyed 910 miles of southeast Idaho highways for the presence of monarchs and identified the number and location of showy milkweed patches (Asclepias speciosa – the obligate host plant of monarch larva). Thomas also noted the abundance and variety of other butterflies, bees, and native and non-native plants found in the roadside habitats.

The researchers were surprised to find that showy milkweed was quite common along SE Idaho highways, while monarch butterfly numbers had decreased alarmingly in 2021 and 2022. They were also surprised that bee variety and quantity was higher in secondary highway roadsides compared to primary and interstate ROWs, as well as areas dominated by native plants.

“Our study found that areas with diverse native flora and sagebrush steppe, in particular,” said Dr. Debinski, “had significantly higher bee richness and abundance than other sites.” At the same time, the abundance of butterflies depended almost entirely on the number of flowering plants, native or not.

The field study also developed roadside management recommendations to help insects overcome the downside of living and breeding in the ROWs. “Collisions with vehicles, pollutants, herbicides, insecticides, and disturbance caused by management practices were all hazards associated with bee and butterfly use of roadsides,” explained Dr. Debinski. “One of the goals of this research was to understand the best way to manage those areas for pollinators.” This is particularly true for monarchs, which are experiencing critically low population numbers, cannot afford to lay eggs or have their larva feed on plants that will be cut or sprayed in the middle of their lifecycle.

“Bees and Butterflies in Roadside Habitats” expressed concern that roadside habitats could become traps, luring pollinators in with healthy ecosystems and then collapsing population numbers through highway management practices or pollution. To avoid creating a population sink, the report recommended a suite of good practices, from protecting all roadside milkweed patches from herbicides and mowing, mowing smaller portions of the ROW with less frequency and never after flowering, and using pollinator-safe mowers, to spot treating weeds rather than applying herbicides to the entire roadside.

Overall, the research revealed that land along southeast Idaho highways, particularly those with lower traffic levels, was supporting a wide variety of pollinators and could provide an important role in pollinator conservation. “This is one of those areas in road ecology that is finally receiving the attention it is due, particularly given 85% of all agricultural crops require pollinators,” commented Rob Ament.

However, further research is required. “We need to figure out if roadsides are contributing to pollinator population growth or decline overall,” noted Dr. Debinski. “Future research should also determine whether roadside habitats act as corridors for pollinator dispersal; a catchy idea, but one that needs support from more data.”

Blanketing the Roadsides: Wool Erosion Control Blankets Nurture Revegetation

MSU News is highlighting a successful collaboration between WTI and the Montana Department of Transportation (MDT) to use blankets made of Montana wool to prevent erosion and promote plant growth along highways.  For a recent feature article, Principal Investigator Rob Ament invited MSU news staff to visit the test site along Highway 287 near Three Forks, Montana.  Despite harsh conditions at the site, researchers are observing what Rob calls “vigorous plant growth” where the blankets were placed for field trials.  In addition to the erosion control benefits, the blankets could also have economic benefits by creating a new market for Montana wool.  Check out the article and photos by MSU News, and learn more about the project on the WTI website.

New Paper Released: Environmental challenges for the Belt and Road Initiative

WTI Researcher Tony Clevenger was co author on a recently released paper, “Environmental challenges for the Belt and Road Initiative.” The Belt and Road Initiative will greatly influence the future of global trade. However, it may also promote permanent environmental degradation. We call for rigorous strategic environmental and social assessments, raising the bar for environmental protection worldwide.
View the article here, or on the following web site: NatureResearchSustainability

Can the Next Generation of Wildlife Crossing Structures be Made from Plastic?

WTI Hosts International Workshop to Inspire Creative Designs

In early May, WTI hosted a group of engineers, ecologists, and landscape architects from Canada and the U.S. for a two-day workshop to create innovative designs for wildlife crossing structures. In particular, they were focused on whether a high-strength, fiber reinforced plastic could be used to build bridge-like structures over roadways.  If feasible, using plastic structures could make it easier and less expensive to install wildlife crossing structures in more locations.

The workshop was led by Rob Ament, Program Manager for WTI’s Road Ecology research, and Nina-Marie Lister, Director of the Ecological Design Lab at Canada’s Ryerson University.  Participants were split into two teams to create “competing” designs for prototype wildlife crossings at Hyalite Canyon and Bozeman Pass on Interstate 90.  Also taking part were WTI Research Scientist Tony Clevenger, and graduate student Matt Bell, who is conducting research on wildlife crossing structures while pursuing a Master’s degree in Civil Engineering at MSU.

 MSU News highlighted the workshop in a recent feature story, which is available on the MSU website.

Rob Ament to lead webinar on woolen erosion control products (March 29)

On Thursday, March 29, Road Ecology Program Manager Rob Ament will lead a webinar entitled “Evaluation of Effectiveness and Cost-Benefits of Woolen Roadside Reclamation Products” for the Center for Environmentally Sustainable Transportation in Cold Climates (CESTiCC) at the University of Alaska, Fairbanks. The presentation will focus on Rob’s research, which took a fresh look at wool and explored its potential for incorporation in erosion control blankets (ECBs) and to increase the establishment of vegetation along Montana roadsides after highway construction or other right-of-way disturbances. The project targeted the use of low quality wool that is substandard or unmarketable, thus offering both environmental and economic benefits.

The webinar will be held on Thursday, March 29 at 9:00 a.m. Alaska time (11 a.m. Montana time)

Related Projects:
Evaluation of Effectiveness and Cost Benefits of Woolen Roadside Reclamation Products – 4W5283
Evaluation of Effectiveness and Cost Benefits of Woolen Roadside Reclamation Products – 4W4813

MDT Research Newsletter Profiles Three WTI Projects

WTI research is prominently featured in the new issue of Solutions, the research newsletter of the Montana Department of Transportation.  Three recently completed projects are profiled in feature articles:

  • “Prefabricated Steel Truss/Bridge Deck Systems.” This study was a WTI and MSU Civil Engineering project led by Damon Fick, Tyler Kuehl, Michael Berry, and Jerry Stephens. It evaluated a prototype of a welded steel truss constructed with an integral concrete deck, which has been proposed as a potential alternative for accelerated bridge construction (ABC) projects in Montana. Steel truss bridges are relatively light weight compared with plate girder systems, which makes them a desirable alternative for both material savings and constructability. See the WTI website for more information.
  • “Evaluation of Effectiveness and Cost-Benefits of Woolen Roadside Reclamation Products.” This research project developed three types of products for study: woolen erosion control blankets (ECBs), wool incorporated into wood fiber compost, and wool incorporated into silt fence. The project, supported by Montana Department of Transportation (MDT) and the Center for Environmentally Sustainable Transportation in Cold Climates, compared the wool products’ performance to roadside reclamation products commonly used for revegetating cut slopes. Rob Ament (P.I.) and Eli Cuelho served on the research team. Additional information is available on the WTI website.
  • “Feasibility of Non-Proprietary Ultra-High Performance Concrete (UHPC) for Use in Highway Bridges in Montana.” Ultra-high performance concrete (UHPC) has mechanical and durability properties that far exceed those of conventional concrete. However, using UHPC in conventional concrete applications has been cost prohibitive, costing 20 times that of conventional concrete. The overall objective of the Phase I research was to develop and characterize economical non-proprietary UHPC mixes made with materials readily available in Montana. The research was led by Michael Berry. Additional project information is available on the WTI website.

The MDT Solutions newsletter is available on the MDT website.

Two New Research Reports Released: Wool Reclamation Products and High Performance Concrete

The Montana Department of Transportation has released the final reports for two projects by WTI researchers:

  • “Evaluation of Effectiveness and Cost-Benefits of Woolen Roadside Reclamation Products.” This research project developed three types of products for study: woolen erosion control blankets (ECBs), wool incorporated into wood fiber compost, and wool incorporated into silt fence. The project, supported by Montana Department of Transportation (MDT) and the Center for Environmentally Sustainable Transportation in Cold Climates, compared the wool products’ performance to roadside reclamation products commonly used for revegetating cut slopes. Rob Ament (P.I.) and Eli Cuelho served on the research team. The final report and project summary are available on the MDT website. Additional information and all of the reports related to this project are available on the WTI website.
  • “Feasibility of Non-Proprietary Ultra-High Performance Concrete (UHPC) for Use in Highway Bridges in Montana.” Ultra-high performance concrete (UHPC) has mechanical and durability properties that far exceed those of conventional concrete. However, using UHPC in conventional concrete applications has been cost prohibitive, costing 20 times that of conventional concrete. The overall objective of the Phase I research was to develop and characterize economical non-proprietary UHPC mixes made with materials readily available in Montana. The research was led by Michael Berry. The final report and project summary are available on the MDT website and additional project information is available on the WTI website.