What to look for in nature in Minnesota this May

Which warblers and other migrants pass through Minnesota in May?

• Warblers in breeding plumage

  The first part of May is the best time, per the DNR · Wooded river valleys, lakeshore trees and any park with tall, leafing-out trees

  Warblers move north at night and drop into the nearest trees at dawn, so the best hour is the first one after sunrise. Look along the St. Croix and Minnesota river valleys, where Interstate State Park and the Minnesota Valley National Wildlife Refuge are both described by their managers as stopovers for migrating songbirds. A cool, clear morning after a night of south wind tends to leave birds low and hungry. In the last days of the month the DNR suggests driving up the Gunflint Trail near the Canadian border, where warblers can still be found on the last weekend of May for anyone who missed the main wave farther south.

• Golden-winged warblers at Tamarac

  Spring and early summer, singing from woodland edges · Tamarac National Wildlife Refuge, Becker County

  The U.S. Fish and Wildlife Service says Minnesota hosts 42 percent of the global breeding population of golden-winged warblers, and Tamarac’s lakeshore edges are good habitat. The song is a thin buzz, often written as “zee bee bee bee,” and the bird sings from the tops of low trees at the forest edge. The refuge visitor center lists seasonal hours that begin on May 15, open Wednesday to Saturday in the daytime and on Sunday afternoons; confirm before a long drive, because the trails and wildlife drive are the real draw.

• The tail end of the broad-winged hawk flight

  Peaks run roughly May 1 to 10; the count continues daily through May 31 · West Skyline Parkway, Duluth (Hawk Ridge)

  Hawk Ridge Bird Observatory’s spring guide names the broad-winged hawk as its main May species, with peak days between May 1 and 10 and as many as 3,000 to 4,000 birds a day. Broad-wings travel in rising spirals called kettles on warm, sunny afternoons with a southerly breeze. By mid-May the flight tapers off, but the daily count goes on until the end of the month, and the staff lead naturalist programs on weekends through May.

• Reading the night sky for birds

  Any night in May · Anywhere with a view of a forecast map

  Most songbirds migrate in the dark. Cornell’s BirdCast live migration maps turn weather-radar echoes into a picture of the birds overhead, how many and which way, between local sunset and sunrise. Look at the map in the evening: a bright patch over Minnesota with arrows pointing north means the next morning may be a good one for new arrivals. Radars can go offline, so a blank map is not proof of an empty sky.

Where do prairie chickens, gulls and swans nest in northwestern Minnesota?

• The last of the prairie-chicken booming

  Mornings from mid-March to mid-May, winding down in May · The eastern edge of the Red River Valley, from the Crookston area south toward Fergus Falls

  A Minnesota Conservation Volunteer article on the birds says booming runs every morning from mid-March into mid-May, and that the display wraps up in May. The state’s greater prairie-chickens live mainly in a narrow band along the eastern side of the valley. Watch from a distance and stay in a parked vehicle if you can; birds that are flushed from a booming ground stop displaying. If you want a guided trip, the annual Festival of Birds in Detroit Lakes advertises prairie chicken viewing, described below.

• Detroit Lakes Festival of Birds

  The festival’s own page lists May 20 to 22, 2027, as its 30th annual event · Detroit Lakes, Becker County

  Visit Detroit Lakes, which hosts the festival, shows the 2027 dates as May 20 to 22 and adds “check back for updates.” Its most recent published schedule, for 2026, offered guided bus field trips to Bluestem Prairie, Hamden Slough National Wildlife Refuge and Tamarac National Wildlife Refuge, along with dinner talks, vendors and a silent auction. Sponsors include the Minnesota Prairie Chicken Society and Friends of Tamarac. Registration runs through the Detroit Lakes Chamber, so confirm the 2027 program there.

• Franklin’s gulls, terns and shorebirds at Agassiz

  Late spring; colonies set up in isolated marshes · Agassiz National Wildlife Refuge, Marshall County

  The refuge reports that up to 20,000 pairs of Franklin’s gulls can set up colonies in remote marsh, and that black terns, eared grebes and black-crowned night-herons also nest in colonies. About 7,500 duck pairs nest there in an average year, and mudflats draw phalaropes, sandpipers and plovers on their way north. Two resident wolf packs live on the refuge, and bald eagles have used a nest near the Parker Pool observation deck since 1992.

• Trumpeter swans on their nests

  Nesting in May; the DNR places cygnet hatching in mid-June · Marshes in central and northern Minnesota, including Tamarac and Rice Lake refuges

  The DNR’s seasonal wildlife guide says trumpeter swans can be seen nesting in central and northern marshes, with cygnets hatching in mid-June. Tamarac reports more than 50 successful nesting pairs, and Rice Lake National Wildlife Refuge lists trumpeter swans among its nesters. Use binoculars from a roadside or overlook; an adult sitting on a mound of cattails is not a bird to approach for a better photo.

What is blooming in Minnesota’s woods in May?

• Minnesota dwarf trout lily, the last bloom

  Late April to mid-May, per the U.S. Fish and Wildlife Service · Goodhue, Rice and Steele counties, including Nerstrand Big Woods State Park

  This tiny lily grows only in three southeastern counties and is listed as endangered by both the state and the federal government. Its flowering season runs from late April to mid-May, so early May is the end of it. Large patches of leaves often carry very few flowers. It looks much like the common white trout lily, which has six petals where the dwarf usually has four or five; either way, stay on the boardwalk and trails, because stepping off crushes the plants that spread underground.

• Large-flowered trillium

  May into June · Rich, shaded hardwood forest across the state

  Minnesota Wildflowers calls it the largest trillium in the state: a single white flower above a whorl of three leaves, 8 to 18 inches tall, often aging to pink. Plants take several years to flower from seed, which is the best reason not to pick one. Ants spread the seeds. Interstate State Park lists trillium among the wildflowers along its Sandstone Bluffs Trail, and picking flowers is against park rules.

• Virginia bluebells and Dutchman’s breeches

  April through June for bluebells; early spring for Dutchman’s breeches · Moist woods and river floodplains in the south and east

  Virginia bluebells prefer moist woods and floodplains near streams. They last longer under shade as summer comes. Interstate State Park names Dutchman’s breeches among its early flowers along the St. Croix.

• Showy lady’s slipper, a month away

  June to July · Moist prairies, sedge meadows and fens, and bogs in the north

  Minnesota’s state flower is not a May bloom. Minnesota Wildflowers puts its flowering in June and July, with peak in mid-to-late June, and notes that the site will not publish locations because people dig the plants up. Late May is the time to learn the leaves so you can find the plant when it opens. It is the only state emblem that is an orchid.

When does the last lake ice go, and how do loons nest?

• Ice-out and the fishing opener

  Median early May on the northern border lakes; the latest on record is May 23 · Lake of the Woods, Rainy Lake, Leech Lake and other northern lakes

  The DNR table lists 2018 ice-out as May 14 for Lake of the Woods, May 12 for Rainy Lake and May 11 for Mille Lacs. Mille Lacs’s latest on record is May 16, 2013. The DNR’s season page lists a general fishing opener of May 15, 2027, about two weeks after the median ice-out on the border lakes, so anglers on the far-northern lakes should check conditions and local access before they travel.

• Common loons on their nests

  Loons are usually back by April; incubation runs nearly a month, then chicks ride on a parent’s back · Lakeshores statewide, most of all the northern forest

  Season Watch records for Itasca County show an average first loon call on April 22, and as late as May 21 in 2002, when the ice held on. By May the pairs are on nests at the water’s edge. The DNR says females lay one or two eggs, that both parents share about 28 to 30 days of incubation, and that the parents carry young on their backs to protect them from fish and turtles. The DNR counts roughly 12,000 loons in the state, a number surpassed only in Alaska. A nest at the shore is easy to flush: give it space, keep boats away from shoreline reeds, and watch with binoculars.

• Painted turtles and egg-laying turtles

  Late spring and early summer; no single date · Wetlands and sandy road shoulders statewide

  Interstate State Park notes turtles coming ashore to lay eggs along the St. Croix, and the Minnesota Valley refuge reports snapping and painted turtles laying eggs in wetland areas. Neither source gives a start date, so treat the season as roughly late spring into early summer. If you stop to help a turtle across a road, move it in the direction it was heading.

Which baby animals will you see in May, and what should you do?

• White-tailed deer fawns

  Most fawns are born from mid-May to mid-June, per the DNR · Meadow edges, lawns, tall grass, brushy fields

  The DNR’s wildlife almanac says fawns often lie still while the doe watches from nearby, so a fawn alone is likely fine. Don’t touch or move it; if it looks wounded or truly orphaned, consult a wildlife rehabilitator first, since moving a fawn can harm it and spread disease. Keep dogs leashed so they don’t flush a bedded fawn.

• Moose calves

  Cows give birth in May or June, per the DNR · The northeastern and northwestern forests and bogs

  A new moose calf weighs about 25 to 35 pounds and can walk and swim within a week. The DNR describes moose as seldom aggressive, with two exceptions: a bull in the rut and a cow who feels her calf is in danger. Never put yourself between a cow and a calf, and give the pair far more room than seems necessary.

• Bats and their pups

  Colonies raise pups from May through August · Barns, old trees and bat boxes

  The DNR says females usually have one pup a year, and that exclusions at buildings should wait until pups can fly because flightless young can be abandoned. A bat resting on a wall in spring may be a migrant that will leave after two or three days. White-nose syndrome, first confirmed in Minnesota in the winter of 2016 to 2017 at Forestville/Mystery Cave State Park, cut the number of bats at Soudan Underground Mine and Mystery Cave by more than 90 percent by 2021, so every healthy colony counts.

• Black bears out and about

  Mating season runs May through July · Northern forest and its edges

  According to the DNR, cubs arrive in January, and they usually leave the den in early April. In its spring advice on living with bears, it recommends taking down bird feeders, because bird feeders can become bear feeders, and keeping garbage, grills and pet food out of reach. A bear that finds food once will likely return.

Which frogs call in May, and are morels up?

• American toads and gray treefrogs

  American toad early May to early June; gray treefrog late May to late June · Shallow ponds, ditches, wetland edges and woodland pools

  The DNR’s calendar has the American toad’s long, musical trill running from early May to early June, then the gray treefrog’s short, bird-like trill beginning in late May and continuing into late June. Spring peepers and northern leopard frogs are at the end of their season by early May, and green frogs, whose call is a twanged banjo string, begin in early June. Weather can nudge every date.

• Morel mushrooms

  Late April through May in the south; into June in the north, per University of Minnesota Extension · Hardwood woods after spring rain

  Extension says morels appear after adequate rainfall. It stresses “when in doubt, throw it out,” warns that the false morel is poisonous, and recommends cutting the stem just above the soil and carrying the mushrooms in an onion bag. For poison questions it gives Poison Control, 1-800-222-1222. It does not cover harvest rules on state land, so check with the DNR before collecting in a state park or forest.

How warm is May in Minnesota, and what can the weather do?

• Severe weather ramps up

  May averages 5.7 tornadoes; June is the peak · Statewide; the south and west see the most storm days

  Tornado counts kept by the State Climatology Office for 1991 to 2020 give an annual average of about 46 tornadoes in Minnesota, with 5.7 (13.0 percent) in May, 14.2 in June and 11.7 in July. More than 85 percent of the state’s tornadoes happen between May and August, and most come between 2 p.m. and 9 p.m. Pick your safest room before a storm day begins. The NWS office in the Twin Cities holds Severe Weather Awareness Week each April with statewide drills, a good reminder for the month ahead.

• A late freeze is still possible

  The median last freeze runs from late April in the Twin Cities to May 29 at International Falls · North of the Twin Cities most of all

  In an average May, Duluth records about 3.6 freezing nights and International Falls about 8.8, against 0.5 at Minneapolis/St. Paul. Snow in May is rare: Duluth’s normal is 0.8 inch and the Twin Cities’ is zero. Garden transplants in the north often wait for the “nine years in ten” column of the table below rather than the median.

• Fire danger before the full green-up

  After the snow is gone and before vegetation greens up · Dry grass and brush, mostly in the north and west in early May

  The DNR describes the weeks between snowmelt and green-up as a risky time for wildfire. Look up the statewide fire danger and burning restrictions first, apply for a burning permit online where one is required, and keep campfires to about three feet across and three feet tall at most.

When is the last spring freeze in Minnesota?

How much daylight does Minnesota gain in May?

What can you see in the Minnesota sky in May?

• Eta Aquariid meteors

  Strongest on the mornings of May 5, 6 and 7; active from about April 19 to May 28 · Southeast sky in the final hours before dawn

  The shower peaks about May 5 to 6, with a thin crescent Moon, one to two percent lit, giving no interference. Their radiant in Aquarius climbs above the horizon barely an hour or two ahead of sunrise this far north, so Minnesota sees fewer than southern states: expect rates of 10 to 30 per hour in the southern two-thirds of the country in the last hours before dawn, and noticeably fewer here. Lie back facing southeast with no lights.

• Flower Moon and seasonal Blue Moon

  Full at 5:59 a.m. CDT on Thursday, May 20; the rounder-looking evening is Wednesday, May 19 · Climbing out of the eastern horizon at dusk

  Flower Moon is the traditional almanac name. By the older seasonal rule it is also a Blue Moon, the third of four full moons in the spring that runs March 20 to June 21; by the modern calendar-month rule there is none in 2027. It becomes full before sunrise on the 20th. Minneapolis moonrise on May 19 is about 8:29 p.m. by our calculation, and the moon looks round that evening and the next.

• Mercury at dusk

  Evenings from about May 12 into early June, widest on May 27 and 28 · Just above the northwestern horizon after sunset, well before the sky is dark

  Late May brings Mercury’s finest dusk showing of the year, about 23 degrees from the Sun, at its widest on May 28. Our computations for the central US have it setting well over an hour after the Sun in mid-May, and a little later still around June 1, as it dims from a bright minus 0.6 to a faint plus 0.9. Use a flat horizon and binoculars if the sky is hazy; it fades fast in June.

• Venus and Saturn before dawn; Jupiter at dusk

  Venus and Saturn close May 7; first-quarter Moon beside Jupiter on May 12 · Eastern horizon at dawn; Jupiter high in the evening

  The two planets reach their closest, 0.6 degrees, during the daylight of May 7; on the mornings either side they sit about one degree apart. Both hug the eastern horizon in twilight, so scan with binoculars from a spot with a clear low view. Jupiter stays in the evening sky all month; the first-quarter Moon passes near it the evening of May 12.

What can Minnesota families do outside in May?

Safety notes for May in Minnesota

• Spring turkey seasons

  D May 5 to 11, E May 12 to 18, F May 19 to 31, 2027; youth and archery through May 31 · Statewide

  In the DNR’s 2027 table, firearm season D covers May 5 to 11, E covers May 12 to 18 and F covers May 19 to 31, while youth and archery hunters have April 14 through May 31. Check the regulations for licenses and shooting hours. Hunters wear camouflage and call from the ground, so a walker on public land at dawn should speak up and wear something bright.

• Blaze orange

  Not required for turkey · Statewide

  On its blaze clothing page the DNR names turkey hunting among the exceptions to the small-game requirement when no deer season is open, and the bear hunt is listed as an exception too. Its lottery deadline for the 2027 bear hunt is May 7.

• Ticks

  Adult blacklegged ticks peak in May; nymphs become active in mid-May, peaking late May through June · Wooded and brushy areas

  The Minnesota Department of Health says adults emerge right after snowmelt, peak in May and stay active through June, while nymphs start mid-May. Stay on mowed trails, wear light clothing, check yourself and pets after time outdoors, and remove ticks promptly: blacklegged ticks usually need 24 to 48 hours attached to transmit Lyme disease.

• Cold water and late ice

  All month on northern lakes · Boundary lakes and Lake Superior

  With ice-out dates as late as May 23, the far-northern lakes can still carry ice or float it on the wind in opener week. The water is cold, so wear a life jacket and avoid shore ice that has pulled away.

• Storms and burn rules

  Afternoons and evenings · Statewide

  Know your safest room and where you would shelter on a boat or trail. If you light a burn pile or campfire, follow the DNR’s fire guidance, and keep fires small.

• Caves, mushrooms and nests

  Season-long · Caves and woods

  Honor cave closures to protect bats from white-nose syndrome, and wash gear after any cave visit. Eat only wild mushrooms you can identify with certainty.