What of otters?

Fort Snelling State Park

1-2 p.m. Friday

Ever wondered why otters spend so much time in the water? Is an otter's fur soft or rough? Join a naturalist for a short hike to learn about these playful, water-loving creatures. Bug spray, sunscreen, water and good hiking shoes are recommended. (612-725-2724, mndnr.gov)

Tag monarchs

Flandrau State Park

4-5 p.m. Saturday

Learn about monarch butterflies in Minnesota. There will be attempts to tag some, too. The insect is nearing its fall migration cycle to Mexico. (1-507-384-8890, mndnr.gov)

Prairie meditation

Buffalo River State Park

5:30-6:30 p.m. Saturday

Join a prairie mediation experience that will help you re-center. Take a walk and immerse yourself in the tall grasses of this local ecosystem. (mndnr.gov, 218-498-2124)

Macroinvertebrates

Minneopa State Park

1-2 p.m. Sunday

Macroinvertebrates are aquatic bugs that can be seen, that have no backbone, and that live in our rivers, lakes and wetlands. Discover how the aquatic bugs are special and where to find them. We will collect the insects from the Minneopa Creek and identify each of them using a simple identification key. (1-507-384-8890, mndnr.gov)

Glacial pothole tours

Interstate State Park

Noon-1 p.m. Friday, Saturday, Sunday and Monday

Experience the stunning scenery and incredible story of Interstate State Park. An interpretive naturalist will lead you over, under and through world-renowned rock features. Discover how lakes of lava and gushing glacial waters formed the unique glacial potholes and even step inside one. The program is for all ages. Expect some uneven terrain and stairs. (651-465-5711, ext. 225, mndnr.gov)

Bird banding

Whitewater State Park

12:30-2 p.m. Sunday

Handle and release birds after they've been caught, studied, and banded with an aluminum tag. (1-507-312-2300, mndnr.gov)

Bike sprint

Elm Creek Park Reserve

6-8 p.m. Monday

Head to Champlin for the continuing Dirt Cup series. The race is on a 10-plus-mile single-track loop. There are divisions for men, women and youth (ages 14 and older). Races rotate among Elm Creek Park Reserve, Lake Rebecca Park Reserve and Murphy-Hanrehan Park Reserve. Registration starts at 6 p.m., with the racing at 6:30 p.m. Preregistration is $12; race day $15. Call 763-559-6700 to preregister. (threeriversparks.org)