University of St. Thomas
OP-10: Biodiversity

The St. Paul campus is adjacent to the Mississippi Gorge Regional Park portion of the Mississippi National River and Recreation Area. According to the National Park Service,

"The Mississippi River's character changes more throughout the 72 mile (115 km) stretch of the Mississippi National River and Recreation Area than anywhere else along its 2,350-mile course.

The river enters the northern corridor as a free-flowing prairie river and moves downstream to plunge over St. Anthony Falls and into the river's narrowest gorge. Eight and one-half miles later, the river exits the gorge to become the country's dominant floodplain river and part of the largest inland navigation system on earth.

Through the eight and one-half mile gorge, the Mississippi drops more than 110 feet, the river's steepest descent anywhere. The river's rapidly changing character explains why the national river and recreation area has such a unique concentration of nationally significant resources."

Source: "Learn About the Park." Mississippi National River and Recreation Area. National Park Service, 2 July. 2018. Website: https://www.nps.gov/miss/learn/index.htm

A mere two-lane road separates the Mississippi National River and Recreation Area from the westernmost block of University of St Thomas’ property. This four-acre piece of land is managed as parkland and consists mainly of trees and sod except for a 10,000 square foot slice that is the heart of the St. Thomas Pollinator Path – the Biology Stewardship Garden and several Pollinator Path beds. The species diversity of insects at this site is greater than at any of the other sites on campus. Our working hypothesis is that this richness is due to its proximity to the Mississippi river. We see the other beds on campus as habitat fragments that provide additional forage to the pollinators that may originate from these nearby natural areas.

Rusty-patched bumblebee, and other Minnesota native bees. In addition to bees, the Pollinator Path provides important forage for Monarch butterflies. The Monarch butterfly is currently being considered for listing as an endangered species by the U.S. Fish and Wildlife Service. The Xerces Society and the International Union for the Conservation of Nature (IUCN) have determined that 28% of the bumble bees in North America are threatened with extinction. Our Pollinator Path over the past 5 years has provided homes and food for eight different species of bumble bees, including a significant number of endangered Rusty-Patched Bumble Bees. We have also seen a small number of American Bumble Bees, which are declining in Minnesota and are considered a threatened species. Other small native bees are commonly found visiting flowers on the Pollinator Path such as sweat bees, cellophane bees, mining bees, yellow-faced bees, cuckoo bees, leaf-cutter bees and mason bees. NatureServe considers that a significant amount of leaf-cutter bee (50%) and mason bee species (28%) are “at risk” for extinction. Anecdotally, we have seen a decrease in leaf-cutter bee sightings on campus over the past 2 years.

The Pollinator Path beds are managed by the Biology Greenhouse Manager, and co-founder of the Pollinator Path, Catherine Grant. The beds are protected areas designed to attract the Rusty-Patched bumble bee and many other native pollinators. The beds provide forage for pollinators and many of the beds are planted with Minnesota native species. There are over 89 perennial species in the designated beds, and 46 annuals, all selected for their value to pollinators.

There are two data sets being collected to monitor the pollinators that forage in the Pollinator Path beds. The first set is based on annual population assessments conducted by the students in the fall semester Conservation Biology class. They visit specified sites and categorize the pollinators they see in general classes, such as “bumblebee, honeybee, butterfly,” etc.

The second data set is being collected by Doreen Schroeder, Biology staff and co-founder of the Pollinator Path. She has five years’ worth of data based on a weekly population census taken from June through September. Her data is much more specific as to type of pollinator – with 30 categories – and records which plant species are hosting which pollinator type.

The student-collected assessments date back over five years and include data collected before the Pollinator Path was established, giving an important benchmark. The data shows a threefold increase in bumblebees since the Pollinator Path introduced new forage, and a six-fold increase in honeybees – although that may be attributable to more managed hives in the surrounding St. Paul neighborhoods.

The data collected by Doreen Schroeder spans five years thus far and is noted for the level of specificity as to bee type and flower species.

Since 2018, 1,857 square feet of Pollinator Path beds have been installed, and 9,264 square feet of pollinator friendly plantings have been installed. This is a 72% increase. The plans/programs at University of St. Thomas to protect & positively affect pollinator habitat include:

1. The “branding” of the Pollinator Path by the marketing team to designate the sites as official. Each site is marked by an educational sign. An informational flyer is available at key sites with a map of all nine sites and links to the Biology Department website with more in depth information on the Pollinator Path.

2. The Biology Department supports the efforts of the two co-founders to establish, maintain, expand, and do research on the Pollinator Path sites.

3. The use of the Pollinator Path as a living lab for dozens of undergraduate class projects administered through the Sustainable Communities Partnership out of the Office of Sustainability Initiatives.

4. Collaboration between the Grounds staff and Biology to establish, maintain and increase the footprint of pollinator habitat on the St Paul campus since 2016. As of summer, 2019, the Pollinator Path beds comprised 14,525 square feet. An additional 1,857 square feet were added in 2020. In addition to the nine official pollinator path beds, the university’s grounds crew have installed approximately 10,000 square feet of pollinator-friendly plantings in other locations across campus.

Information for this credit was provided by Pollinator Path co-founders, Catherine Grant and Doreen Schroeder, and Ground Supervisor, Jeff Voshell.

Pollinator Path Website: https://cas.stthomas.edu/departments/areas-of-study/biology/facilities/pollinator-path/