2025 BioBlitz Summary Report

Disclaimer: The geolocation settings applied during data collection may capture information from areas adjacent to Louisville. As a result, some findings may reflect the general region rather than the city limits specifically.

A BioBlitz is an intensive biological inventory in which experts and community members work together to document all living species—plants, animals, and invertebrates—within a designated area and timeframe. What sets this event apart is its scientific rigor: field surveys were led by biologists using standardized protocols, producing high-quality data with long-term value for conservation planning. It was the first event of its kind held in Louisville.

Data Collection

Data was collected using iNaturalist, GPS tools, and field surveys. In total, CNHP made over 1216 species observations across 15 sites. Notable finds included

• rare plants
• a rare bumblebee
• a potentially undescribed mushroom species

Overall, the results show high biodiversity across Louisville’s open spaces, with both healthy native species and ongoing impacts from non-native plants.

 Botany (Plants)

• A total of 468 plant species were documented across Louisville’s open spaces.
• Six rare or tracked plants were confirmed, including narrow-leaved milkweed and fireberry hawthorn.
• The most observed plants during the BioBlitz included showy milkweed, western wheatgrass, and narrowleaf willow.
• Two open space areas—Davidson Mesa and Aquarius—contained patches of recovering native grassland.
• 23 species were Colorado-listed noxious weeds, showing ongoing management needs.

Vegetation Ecology (Plant Communities)

• Native grasses recorded at Davidson Mesa, including Andropogon gerardii, Pascopyrum smithii, Hesperostipa comata, and Bouteloua curtipendula, suggest the site may once have been representative of the globally vulnerable ecosystem (Southern Great Plains Mixedgrass Prairie) (G133)
• Davidson Mesa’s northwest slope showed the most natural species mix, with big bluestem, needle-and-thread, prairie junegrass, and other natives.
• Riparian and wetland vegetation along Coal Creek and Dutch Creek included both native willows and cottonwoods, as well as dominant non-natives like crack willow.
• Two sites—Davidson Mesa and Aquarius—were mapped as recovering native grassland due to stronger native species presence.

Entomology (Insects)

• Surveys documented 480 arthropod species, reflecting strong insect diversity across habitats.
• Two rare or tracked species were found: the Western Bumble Bee and the Red-veined Meadowfly.
• Sampling methods included sweep nets, dip nets, and nighttime UV light traps.
• Insects were found in wetlands, grasslands, riparian areas, and prairie dog towns.
• All observations were verified through iNaturalist to ensure accurate species identification.

Zoology (Animals)

• Wildlife surveys recorded birds, amphibians, reptiles, small mammals, bats, and mollusks across multiple open space areas.
• Three tracked animal species were found: Black-tailed Prairie Dog, Hoary Bat, and Silver-haired Bat.
• Surveys used direct observation, auditory detection, GPS mapping, and acoustic bat recorders.
• Bird surveys documented species using grasslands, wetlands, and riparian corridors

Wetland Ecology, Herpetology, Mycology & Bryology (Water Organisms, Reptiles/Amphibians, Fungi, & Mosses)

• Wetland surveys documented plants in ponds, marshes, and riparian corridors, including bulrushes, sedges, and cattails.
• Three moss species were recorded: Brachythecium erythorrhizon, Amblystegium serpens, and Cratoneuron filicinum.
• Fungal surveys recorded multiple mushrooms, including a blue-stemmed fungus that may be an undescribed species in the genus Entocybe.
• Fungi were found on decaying wood, shaded soils, and leaf litter across grassland and riparian areas.
• Wetland vegetation data will support future mapping and conservation planning for Louisville’s open spaces.

The project successfully met its objectives of expanding biodiversity data, strengthening community engagement, and contributing to ongoing conservation planning for the City of Louisville’s natural areas. Detailed findings are available in the City of Louisville Open Space BioBlitz Summary Report.