A smooth start to the first emergence trapping deployment! Today we placed 23 traps at three sites, making good use of our new color-coded flagging system. So cool to see our work from the last few weeks starting to pay off!
Some emergence trapping sites are a lot smaller than others! It will be interesting to see whether size is associated with catch rate. Do bees prefer to nest in big sites? REU student Zach deploys a trap at our first site of the day. This site was burned earlier in the spring, can you see how short the vegetation is?
These traps will be out for four days, then emptied and sent back out to new sites on Monday. Fingers crossed we’ll see some bees!
NOTE: Funding for this project was provided by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR).
As part of my recent independent study with Stuart and Northwestern undergrad Lena Parnassa this spring, I took an initial pass at analyzing the data from our 2023 emergence traps. These data are an important contribution to the broader ENRTF project, which is geared at understanding how ground-nesting bees respond to prescribed fire in prairies. This independent study enabled me to learn a great deal about database organization, coding, and collaboration between data scientists. Before we could run any of our analyses, we had to wade through quite a bit of data cleaning to ensure all our joins were functioning properly. This meant that we had to prioritize the bee analysis rather than the bycatch in our traps (millipedes, grasshoppers, and so forth), so stay tuned for more in that department! We were also working with abundance data rather than species data, as identifications of all the bees we caught in 2023 are still forthcoming. This means that some of the data points in our analysis are most likely incidental, but nevertheless, here’s a visual of what we found!
Figure 1: Mean bee catch rate by site type. Catch rate refers to the proportion of traps which had bees.
Figure 2: Bee catch rate by site. Catch rate refers to the proportion of traps which had bees.
Mean bee catch rate by burn history. Only three sites were 3 years post-burn in 2023, other burn treatments had 7-8 sites.
It looks like remnant prairies had more bees than restorations, but there’s a ton of variation across sites of the same land use type. It’ll be interesting to see what other factors may be associated with this variation, if any. Once we get those species ID’s and confer with our taxonomist, we’d like to tweak our protocol slightly going into this summer to maximize our chances of catching the bees at a given site. We’re considering stocking our traps with propylene glycol to better preserve specimens, trimming the vegetation around traps to make sure bees can find the entrance, and deploying later in the day to give foraging bees time to find their way back to their nests. Looking forward to kicking of the 2024 trapping season!
NOTE: Funding for this project was provided by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR).
Members of Team Echinacea are freshly returned from a successful burn outing! We completed five experimental burns during our trip to western MN. A major win for the experimental design of our MN ENRTF funded research on prescribed fire and ground nesting bees as well as for conservation! Here is the scoop:
Late Friday night we got to the Hjelm House and were lucky enough to catch a glimpse of the Aurora Borealis. In hindsight, I think this auspicious sighting boded well for our good fortune in burning conditions.
On Saturday morning we headed to Torgeson’s to burn the northern unit. Because it was predicted to be a dry day, we got an early start and were ready to burn by 10:45. We got to see lots of spring flora before the burn: pucoons, violets, sedges, pussytoes, etc… These plants will be even happier next year. With help from Lee, the burn went very smoothly. Torgeson’s is a hilly site, so the burn was slope driven and we had a great view. Things are pretty greened up in the area, so the burn was quite smoky. USFWS, who were burning a big restoration right next door must have been burning cattails- look at that thick, brown smoke coming from the other side of the road. Almost like we are having bonfires at neighboring campsites. Cute!
Jared secures the break at torgen before we stand back and watch the fire burn out.
Next we ventured into Grant County. No burning there- and if you’ve been following along that may not be a surprise to you. So it was back to Douglas Co. After lunch the crew headed to hutch to burn the western unit. Another Hilly site. We prepped our breaks and were ready to go! Burn number 2 down!
Sunday was a no-burn day because wildfire smoke from Canada was hanging over many counties in MN. A great day to get work done on the porch and venture into Morris to revisit old haunts. We anxiously awaited the next day’s updated report on burn restrictions.
Monday morning we got the go ahead to burn in Grant county!! We called in our backups (former team members Daytona and Liam plus a few of Liam’s friends) and headed to Yellow Orchid Hill West to train our first time burners in at a smaller site. The wind was squirrely but our burn was successful and we were just a hop, skip and a jump away from the revered hulze unit. After 3 failed attempts, was this finally our day?
Stuart and Jared watch the last flames burn out in the center of hulze.
Yes! Drive down highway 55 and you will see for yourself! A hilly expanse of charred earth! A sight for sore eyes after the last burn way, way back in 2003.
By this time, restrictions were lifted in Douglas Co. and the crew headed to Nice Island for a final burn before calling it a day and heading back to the farmhouse. Over Jean’s rhubarb cake we envisioned a utopian or maybe dystopian future on team Echinacea where we have a high tech call center and everything is drone operated. We’ll keep you posted on the call center and the rest of the burns we hope to get done this season.
There are so many interesting questions to ask within the study design of our MN ENRTF funded research on prescribed fire and ground nesting bees! We are lucky to collaborate with researchers in the area who are taking them on.
Justin presents his research at the MSU-Mankato research symposium
Justin Kjorness, undergraduate at Minnesota State University-Mankato, worked with Drs. Mrganka De and Matt Kaproth (and many more) to collect soil samples at our remnants and restorations this summer. He has since been asking questions about the effects of prescribed fire regimes on soil physical properties. He presented these results at the MSU-Mankato research symposium this week!
Ants are an integral part of ecosystems, playing a role in seed dispersal, detritus removal, pest predation, and nutrient cycling. Because ants nest in the ground, they are particularly susceptible to any process that disturbs the earth and can be heavily impacted by land use practices and management decisions. Diane Roeder, at Augustana University, designed this survey to quantify ant species diversity in remnant and restored prairie patches in western MN. These sites are primarily managed by fire, a type of disturbance that has been hypothesized to impact ant species differently via mortality and/or changes in habitat structure. During the summer, Diane and members of team Echinacea sampled 45 prairie sites (30 remnant, 15 restored), deploying a total of 415 pitfall traps. Diane and her colleagues are in the process of sorting ants from other ground-dwelling invertebrates captured by the traps and will identify specimens to compare abundance, species richness, and community composition from sites under different management regimes. In addition to measuring diversity, They also deployed sentinel prey items to determine whether arthropod communities in these areas remove prey at different rates as a measure of ecosystem services provided by predatory arthropods. To do this, they set out small cages containing moth eggs and recorded the number of eggs removed. In the future, Diane hopes to compare the overall arthropod communities between these types of sites from multiple years of sampling.
Diane traveled all over our study area during her few days in Western Minnesota.
This pitfall trap was set up at a random bb point in our study area.
Start year: 2023
Location: Prairie remnants and restorations in Solem Township, MN.
During the summer of 2023, Team Echinacea embarked on an ENRTF funded mission to better understand how prescribed fires influences solitary bee nesting habitat, food resources, and diversity is critical for providing recommendations about how prescribed fire should be used to promote pollinator conservation and healthy prairie.
We surveyed solitary bee diversity and nesting habitat before and after prescribed fires in a subset of 30 prairie remnants and 15 prairie restorations to determine how prescribed fire affects solitary bee nesting habitat and abundance. We used emergence traps to investigate composition of solitary bees in prairies. This was complemented by detailed measures of soil and litter to characterize how prescribed burning influences the nesting habitat (read more here).
We deployed emergence traps at our random points (bb points) in prairie remnants and restorations in mid-June – early September. Our deployment spanned three rotations of bb points and we put out a total of ~1,238 emergence traps.
El, Luke, and Jan, 2023 pollinator crew, deploy an emergence trap at a bb point.
As of September 28, members of Team Echinacea had processed 850 vials, 122 of which contained bees. Our preliminary catch rate is 14%! These specimens were pinned and are currently at Chicago Botanic Garden, awaiting transportation to University of Minnesota where Zach Portman, a bee taxonomist, will identify them. Team Echinacea also collected lots of non-bee bycatch while processing specimens collected in the traps. Bycatch is currently stored in our freezer at Chicago Botanic Garden.
Jan pins a bee that they found while processing vials from emergence trapping!
Ian Roberts, a M.S. student with the Echinacea Project, has taken charge of the Emergence trapping project and is currently coordinating data entry. When emergence trapping resumes in the 2024 field season, we will be well set up, thanks to detailed written and videotaped protocols made by our summer 2023 pollinator team. The prtocol can be found here: “~/Dropbox/enrtf/emergenceTrapping2023/Emergence Trap Protocol.pdf”. Video instructions are located in “~/Dropbox/enrtf/emergenceTrapping2023/exampleVideos”.
Start year: 2023
Location: prairie remnants and restorations in Solem Township, MN.
For the ENRTF-funded research project investigating fire effects on ground-nesting bees, plant-pollinator interactions, and other insects within fragmented prairies, Team Echinacea sampled 45 total prairie sites (30 remnants and 15 restorations).
To obtain robust inferences, it is important to sample randomly so that our sampling effort is not biased by what we perceive to be “good” or “bad” habitat, even subconsciously. To this end, we sampled at random locations within each site. At each site, we established between 30 and 72 sampling locations with unique identifiers (four-digit bbpts, for “burning and bees sampling points”). Early in the summer, before sampling at these points began, we ground truthed the points to ensure we were not choosing in places where we could not sample at all (e.g., think a big rock, a water body, a big patch of poison ivy, a gravel road, etc.).
Jared generated a large number of random points for each site, more points than we actually intended to sample. trap. We visited these points using a high precision gps unit and evaluated whether to “keep” the points and assign them a bbpt or “reject” the point if it could not be sampled safely or effectively.
Jan, 2023 pollinator team member, ground truths bb points at Torgen.
Start year: 2023
Location: prairie remnants and restorations in Solem Township, MN
Overlaps with: ground nesting bees, fire x fragmentation, soils in remnants and restorations, floral resources in remnants and restorations, microhabitats in prairie remnants and restorations
Data collected: spatial locations of accepted bb points are in “~/Dropbox/geospatialDataBackup2023/convertedXML2023/bbptsForEnrtf”. Maps of bb points are located in “~/Dropbox/enrtf/emergenceTrapping2023”
During summer 2023, Team Echinacea Echinacea characterized local environmental conditions to better understand which environmental factors are associated with good habitat for ground-nesting bees. This microhabitat assessment complemented emergence trapping for our ENRTF funded research on fire’s influence on ground nesting bees habitats. We sampled local environmental conditions near randomly placed bbpts in remnants and restorations.
We used a light meter to quantify light availability via a measure of photosynthetically active radiation. We took PAR readings at 1 meter and at ground level ~40 cm NE of the bb point. We also used a soil penetrometer to quantify soil compaction at ~40 cm NE of the bb point.
Team Echinacea conducted microhabitat assessments for three rotations of bb points (rotations 1,2,&3) across 46 sites. Over the summer, we took microhabitat assessment measurements at a total of 1,238 bb points.
Blaire, high school participant 2023, takes a light measurement at a bb point. We were particular about position and timeframe to ensure consistent measurements.
Start year: 2023
Location: prairie remnants and restorations in Solem Township, MN
Data collected: light availability (par measurements) and Soil Compaction (psi measurements) are stored in ~Repos/bbnest/data/microhabitatDataCuration/curate2023MicrohabitatData.R
We’re interested in investigating what resources are available to Echinacea visitors and learning more about the pollen and nectar Echinacea produces. We hope to learn if the nutritional resources available differ before and after burns. In 2022, Britney House developed methods for collecting nectar from Echinacea using microcapillary tubes. Read more about her methods here.
During the summer of 2023, the team collected pollen and nectar samples from Echinacea angustifolia at 19 sites in and around Solem Township, MN (plants at Hegg Lake were Echinacea pallida). We searched for and shot the ~20 plants (or, if few were available, as many as we could find) at each site that were closest to a random point. We then selected ten of those plants to bag up to three of their heads with pollinator exclusion bags. Throughout the duration of their flowering, we collected pollen from all bagged plants and nectar from five of them per site.
Stuart collects nectar from an Echinacea head
Midway through the experiment (mid-July), we removed bags from some of the pollen only plants to adjust our sample size to only the five pollen/nectar plants plus two backups per site. We removed bags from pollen/nectar plants and backup plants when they were done flowering, we’d collected a cumulative 50 mm of nectar from them, or we had received less than 15 mm of nectar from the plant in the last three visits (the latter was more of a guideline than a rule, used to save time by eliminating plants that were unlikely to provide us with enough nectar for analysis). At the Hegg pallida restoration, any heads that were not originally bagged were decapitated, and all heads were decapitated upon the final removal of their bags.
Following some experimentation, we conducted nectar collection only in the afternoons, while pollen collection could be done any time of day. In total, we collected 856 vials of pollen and 580 vials of nectar from 104 plants. These were given to Rahul Roy and Margaret Medini at St. Catherine University in St. Paul, who will be doing data analysis.
Data entry for collection datasheets is complete, and verified csvs for each site can be found at: Dropbox/teamEchinacea2023/z.pollenNectarDataEntry/coreVerified. Scans can be found at: Dropbox/teamEchinacea2023/z.pollenNectarDataEntry/scans.
Start year: 2023
Location: Various prairie remnants and one restoration (Hegg Pallida) around Solem Township, MN
During the summer of 2023, Team Echinacea conducted floral surveys at randomly selected bb points in remnant prairies and restorations. We are interested in quantifying floral resources (i.e., food for bees) and we want to understand how fire influences the diversity and abundance of flowering plants.
At each focal point (bbpt) we identified species rooted within a 2 meter radius and recorded the furthest stage of development. We measured abundance by binning a range of floral units (i.e., 1-5 flowering units got label “5”).
Floral surveys were split into “visit group A” and “visit group B”. We surveyed different random points when revisiting sites. In total, we conducted 415 floral surveys across 45 sites.
Liam Poitra, a 2023 Summer Research Experience for Undergraduates (REU) Participant, contributed to this research project investigating the effects of fire on diversity and abundance of flowering plants. Liam assisted in fieldwork and data organization. Inventory, protocols, and blank datasheets for floral assessments are located in ~/Dropbox/enrtf/floralSurveys2023.
Liam Poitra, REU 2023, navigates to a floral assessment focal point at Staffanson Prairie Preserve. The 2-meter stick he carries will help keep track of what is in the bounds for survey.
Start year: 2023
Location: prairie remnants and restorations in Solem Township
