Afton State Park phenology April 26 to May 2

Birds are singing, flowers are blooming, frogs are calling.




4 minute read

Rue anemone, Afton State Park (silenceinthew00ds/iNaturalist)


On Wednesday the 1st of May get up early and look in the eastern sky for Saturn, which will be pretty bright. Below it you may see Mars, which will not be as bright but is recognizable from its orange-red color. And if you are in a dark place with a clear view to the horizon, you may catch a glimpse of the planet Mercury below Mars.


White-throated sparrows continue to move through our area heading farther north, singing “Old Sam Peabody Peabody”. White-throated Sparrows have striped caps and a white patch on their throats. They look very similar to White-crowned Sparrows, which don’t have the white throat patch.

Chipping Sparrows, which have returned to our area, look quite a bit different – you can identify them by their rusty-red caps.

Eastern Kingbirds are back, too. They have a white band at the end of their tails, and are excellent flycatchers. They sit on a perch and watch for insects, then hover in the air when they fly after them. Swooping out from a perch to catch an insect is called “sallying”.

American Goldfinches are growing new yellow feathers for the summer season, replacing the gray feathers they wore in winter.

And remember listening to Great-horned owls duet hooting back in January and February when they were nesting and laying eggs? The young owlets have hatched and the juveniles are leaving the nests, but that doesn’t mean they’re on their own. The owlets remain with their parents until fall as they learn how to hunt for themselves. One of the animals they sometimes hunt is the skunk. Like most birds owls cannot smell very well, making the skunk’s spray ineffective against them.

Amphibians and Reptiles

Chorus Frogs continue calling, and the Northern Leopard Frogs have joined in. Male Leopard frogs make a low, guttural snoring sound that last two to four seconds. And in early May the tree frogs and toads start calling, too. There are two species of tree frogs at Afton, the Gray Tree Frog and the Cope’s Gray Tree Frog. Both of them can change color from green to gray, and both have yellow patches on the inside of their hind legs. It is hard to tell the two tree frog species apart without hearing their calls, and even then it’s not easy! Both make a very loud trilling call that lasts one to three seconds. People often think they are hearing a bird. The Cope’s Gray Tree Frog’s call is slightly higher-pitched and a little faster than the Gray Tree Frog’s call. The American Toad makes a high-pitched trilling call that goes on for ten to 30 seconds, often with several toads calling at once.


Butterflies are not the only insects to migrate! Last fall juvenile Green Darner Dragonflies flew south, and the offspring of those dragonflies are flying north this spring. They will be the first dragonflies we see here in Minnesota in spring.

Tiger Swallowtail butterflies don’t migrate. They overwinter as pupae with the adult butterflies emerging in late April or early May. Male Tiger Swallowtails are always yellow in color; females may be yellow or black. The black females are uncommon in Minnesota; you are more likely to see them if you travel south.


Some spring ephemerals are still blooming, but they won’t be around long. Some to look for include Cutleaf Toothwort, Downy Yellow Violet, and Shooting Star. And in wet areas look for Blue Flag Iris.

In the woods look for Wild Columbine, Rue Anemone, and False Rue Anemone. What’s the difference between Rue Anemone and False Rue Anemone? Rue Anemone has five to ten petal-like sepals, while False Rue Anemone ALWAYS has only five.

Wild geraniums are blooming in the woods, too, and on the prairie look for prairie phlox.

And continue to keep a lookout for wild strawberry leaves and flowers and remember where you see them. There will be wild strawberries to snack on while you’re hiking before long!!

Weather observations

Here are some weather observations from the Afton State Park area from past years.

Friday, April 262023: pleasant day, near 60°; 2021: light rain through the day; 2011: record rainfall of 1.46 inches;
Saturday, April 272023: light rain off and on through the day, 50s; 2020: light rain the morning, then sunny with temperature in the 60s.
Sunday, April 282020: rain off and on from morning through afternoon; 2004: record high of 91°
Monday, April 292022: in the 50s; 2020: 1” of rain
Tuesday, April 302022,2019, and 2017: rain off and on through the day
Wednesday, May 12022: 40s, light rain through day; 2021: high in the 80s
Thursday, May 22023: windy and sunny, in the 60s; 2019: gray and in the 40s through the day

Photo/Image credits

All photos copyright Nina Manzi, except:

  • Dean Lokken: Eastern Kingbird, Northern Leopard Frog
  • Nathan Pasch, University of Minnesota College of Veterinary Science: Great horned owl nest and egg illustration
  • Gary Sater: American Goldfinch, Great Horned Owl juvenile, dark form of Tiger Swallowtail
  • Tammy Wolfe, MN Conservation Volunteer: Great Horned Owl adult and juvenile


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Afton State Park phenology April 26 to May 2