Afton State Park phenology, Feb. 3 to 16, 2023

Signs of the season include the Sucker Fish Moon, frosted trees, bald eagles, and many animal tracks.




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Hans van Reenen/Flickr


On Friday February 3rd look for the brightest star near the Moon and you’ll be looking at Pollux, which along with the dimmer star Castor are known as Gemini, or the Twins.

Saturday, February 4th is Afton’s candlelight hike event, and if the skies are clear we will have a telescope set up to look at the Moon, which will be full on Sunday February 5th. This month’s full moon is called the Sucker Fish Moon, the Popping Trees Moon, or the Snow Moon. The Sucker Fish Moon is from the Ojibwe people, who relied on spearing sucker fish for food toward the end of winter. The Popping Trees Moon comes from the Lakota people, and refers to the sound made by twigs breaking off of trees in frigid winter winds. Stay warm everyone!


Is that hoar frost, or rime ice? These phenomena look alike, but are formed differently. With our recent run of overcast days following snowfalls we have seen a lot of rime ice forming on trees. Rime ice happens when water droplets in fog freeze directly onto trees, grasses, shrubs, and other surfaces. Rime ice often looks like frozen droplets of water. Hoar frost forms on cold and clear nights, when moisture in the air goes directly from being a vapor or gas to being a solid, skipping the liquid state entirely! (This is called “sublimation”). Hoar frost looks more feathery than rime ice, and often blows away in even a light breeze.


Bald eagles that spend their summers farther north fly south as far as necessary to find open water. Some years they find that open water on the St. Croix near Afton, and you may see them fishing off the ice. You might also see wild turkeys at Afton. And while it’s a myth that Benjamin Franklin argued for the turkey, and not the eagle, to be our national bird, he did express admiration for the turkey, writing that, relative to the eagle, “[The turkey is] a much more respectable Bird, and withal a true original Native of America…He is besides, though a little vain and silly, a Bird of Courage.” Look for turkey tracks in fresh snow. The tracks in the photo show the imprint of one small hind toe, and three large front toes.


All the snow cover this year lets us hunt for tracks of many of the mammals at Afton. Eastern cottontail rabbits have hind feet that are about three inches long, and sometimes when they are hopping from place to place the front feet land together in a single track.

Most of the small tracks in the snow are from mice or voles, and sometimes there are tail marks between the feet.

Deer leave heart-shaped hoof prints, and often will follow the same trails through the woods and fields. Those trails are called . . . deer trails!

Fishers are large members of the weasel family. Look for their tracks near the water. They have big pads and five toes. The tracks can look like the tracks of house cats.

Raccoons and Opossums are not true hibernators, but are active on mild days. Check out the photo of an opossum under the bird feeder at the Visitor Center, taken in January 2008. Their tracks are difficult to tell apart in the snow. If there’s a tail drag mark, or a toe print on the hind foot that slants inward, it’s an opossum.

Insects and arthropods

Bees and fleas? In winter? On mild days in winter bees may leave their hives or overwintering shelters (solitary bees don’t live in hives) and take what are called “cleansing flights”. Bees are notorious for keeping their hives and nests clean, and warm sunny days in winter give them a chance to fly outside and. . . poop!

And on those same mild days you might see what look like flecks of black pepper hopping around on the melting snow. It’s not pepper, but an animal called the “snow flea”. Snow fleas aren’t really fleas, and they aren’t even insects. They’re arthropods, a group that includes spiders and crustaceans. Snow fleas are a type of springtail, and live in the leaf litter of the forest. I don’t have a photo of them, but maybe this winter I’ll get one!

Weather observations

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

Friday, February 32019: above freezing overnight
Saturday, February 42005: record high of 51°; 2021: about 4 inches of snow
Sunday, February 52005: record high of 51°; 2015: below zero; 2022: blustery winds, temperature rising from single digits into 20s
Monday, February 62019: 4 inches of fluffy snow
Tuesday, February 72019: record snowfall of 5.9 inches that started as freezing rain
Wednesday, February 82002: record high of 50°, tied with 1991; 2021: 10° below zero to start the day; 2022 high in the low 40s, first time in the 40s in 2022
Thursday, February 92010: snow continuing from previous day, about 6 inches total
Friday, February 102019: record snowfall of 5.9 inches; 2021: temperature in the single digits; 2022: temperature in the 20s, with lots of birdsong
Saturday, February 112019: 20s in the morning; 2022: freezing rain and snow in the morning, with temperatures falling into the teens in the afternoon.
Sunday, February 122019: record snowfall of 5.5 inches; 2021: high near zero
Monday, February 132017: sunny with a high near 50°; 2022: light snow in the evening, high temperature in the teens
Tuesday, February 142019: 20s in the morning, with a dusting of snow in the afternoon
Wednesday, February 152019: sunny and in the teens for a high
Thursday, February 162017: mild day in the 40s

Photo/Image credits

All photos copyright Nina Manzi, except:

  • Keith Henjum: Raccoon
  • Bill Johnson, MN Conservation Volunteer: Plasterer Bee, Sweat Bee
  • Bill Marchel, MN Conservation Volunteer: single Deer track, Deer
  • Alan C. Nelson, Dembinsky Photo Associates, MN Conservation Volunteer: Harvest Mouse
  • Linda Radimecky: Fisher tracks, Mouse tracks
  • Gary Sater: Full Moon, second Bald Eagle
  • John Watson trail camera: Fisher


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Afton State Park phenology, Feb. 3 to 16, 2023