Written by Ceci Kimball | August 2026
This summer, Nature At The Confluence volunteers went on weekly, staff-led prairie walks every Tuesday evening to observe milkweed plants (the sole host of the monarch butterfly) for the presence of monarch eggs, instars (caterpillars), and butterflies. During these walks, team members identified prairie richness by cataloging flowering species in bloom during the weekly sessions.
The following is a visual analysis of the data collected by staff and volunteers during our Prairie Monitoring sessions during the summer of 2026.
Monarch Findings
Three stages of monarch development were considered when observing organisms in the prairie: eggs, instars (first – fifth), and pupa. Results were uploaded to with the Monarch Larvae Monitoring Project (MLMP), factored again how many milkweed plants were observed week-to-week with an average milkweed weekly sampling rate of 156 plants/week.
The first monarch egg was found on June 9th for a daily total of three eggs. After this initial finding, 28 days passed before another egg would be located. A surge occurred following the second observation of eggs during the prairie monitoring session, beginning on July 7th. Each week after July 7, 2026, evidence of the presence of monarchs was recorded during every monitoring session.
Local findings align to the breeding cycle of the third generation of monarch butterflies occurring in July (great-grandchildren of butterflies born in Mexico), making the month of July, especially early- to mid-July prime breeding season for monarch butterflies at The Confluence. Northern-most breeding ends in August while the fourth generation of monarchs head south and migrate to Mexico for the winter, breeding again in the fall. It is extremely unlikely that prairie monitoring groups will find monarch eggs at Nature At The Confluence after August has ended, given the breeding patterns of this species of butterfly.
Prairie Richness & Biodiversity
Species in bloom were recorded alongside monarch findings during each weekly prairie walk (excluding the first session). Over the course of nine sessions when biodiversity was recorded, 28 unique species were observed. July was the most prolific month for summer blooms with 26 out of the 28 identified species blooming in this month (92.86% of species).
Species were analyzed by the family they belong to with a total of 12 different families represented in the prairie at Nature At The Confluence. The most abundant family found in the prairie was the Daisy, Aster, Sunflower (Asteraceae) family, making up 40% of all recurring families (families with more than one species present in the prairie). The breakdown of each individual species found in the prairie is categorized by family below.
Key Takeaways:
1. Mid- to Late-July is prime breeding season for monarch butterflies at Nature At The Confluence.
2. At least 28 unique species were identified during peak blooms at the Nature At The Confluence prairie in the summer of 2026 (June – August).
3. Peak summer blooms occur most frequently in July with a total of 26 species (92.86% of total identified species) prevalent during this month.
4. The prairie at Nature At The Confluence is home to a variety of species, however those belonging to the Daisy, Aster, Sunflower (Asteraceae) family are the most prevalent over the summer months.
