What to look for in nature in South Dakota this May

Which birds arrive in South Dakota in May?

• Thousands of white pelicans at Lacreek

  Late April and early May, according to the refuge · Pelican Island Trail, about 2.5 miles north of the Lacreek visitor center, near Martin

  The Fish and Wildlife Service says that during late April and early May visitors will see thousands of white pelicans on the islands of this southwestern refuge. The same page lists great blue heron, snowy and cattle egret, double-crested cormorant and black-crowned night heron rookeries on the islands, and names long-billed curlews, burrowing owls, short-eared owls, northern harriers and bobolinks among the birds that come back in spring. South Dakota Birds and Birding adds that pelicans migrate mainly in April and May in the east, nest in colonies on isolated islands and sandbars, and fish as a team: groups line up and herd fish into the shallows. The refuge’s auto tour is a 4.5-mile gravel route, and the page warns that road conditions deteriorate quickly after rain or snowmelt, so ask refuge headquarters before you drive on a wet day.

• Wilson’s phalaropes and avocets in shallow wetlands

  May, with nesting from late May · Prairie wetlands and flooded fields, most of the state

  The Wilson’s phalarope is the bird to learn if you like a good story. South Dakota Birds and Birding calls it a common summer resident through most of the state, a bird of shallow prairie wetlands that feeds by spinning in circles to bring tiny prey to the surface. The roles are reversed: the female is the brighter bird, and after she lays her eggs she leaves, and the male incubates and guards the young alone. Nesting runs from late May into June. American avocets are common migrants and summer breeders in most of the state, according to the same site, which says to look for them in flooded fields during migration, and nesting there runs from May into July. Stand quietly at a wetland edge with binoculars and you may see both in one scan.

• Yellow-headed blackbirds and yellow warblers

  Arriving in spring; nesting late May and June · Cattail marshes, shelterbelts and willow thickets

  Yellow-headed blackbirds are birds of the prairie pothole country. South Dakota Birds and Birding describes them nesting in colonies over water, with the female weaving a deep basket among cattails in late May and June, and the male giving a harsh, harsh, rough song from the stems. Yellow warblers, which that site calls common summer residents across much of the state, favor riparian thickets, wetlands and shelterbelts, and the site gives May through July as their nesting season. The American redstart is a common migrant throughout the state and a common breeder in the west, and the same source says it often forages low enough to be easy to watch. A shelterbelt on a mild morning in the middle of the month is a good place to practice.

• Orioles, hummingbirds and feeders

  Early to mid-May in the east, with big differences from year to year · Eastern South Dakota towns, parks and shelterbelts

  South Dakota Birds and Birding rates the Baltimore oriole a common migrant and breeder in the east, scarcer farther west, nesting there from mid-May, with a preference for open woodland, river edges and shelterbelts. The ruby-throated hummingbird is the only hummingbird commonly found in the eastern half of the state. The site’s author reports that the birds reach his own yard around May 7 each year, which is one observer’s experience and not a statewide date, so watch for the first arrival where you live and log it. Sugar water at a clean feeder, orange fruit for orioles, and tubular red flowers are the usual invitations. Journey North collects hummingbird sightings from across North America, and a report with your date helps the picture build.

• Bluebirds, buntings and sandpipers on the western grassland

  May · West River grassland, the Black Hills foothills and Custer State Park

  The Mountain Bluebird is a fairly common summer resident of western and central South Dakota, and the site names Custer State Park and the Wildlife Loop Road, grassy openings among ponderosa pines, and fencelines as places to look. Nesting runs from May through July. The species takes to a nest box set on a fence post in open ground, with a hole about 1¾ inches wide, and boxes close to buildings often end up occupied by house sparrows. Out on the shortgrass, the lark bunting is a locally common summer resident of the western and central prairie, and the site says it is most likely in the western half of the state. Upland sandpipers, which the same source says can be found easily on native grassland and hayfields, with Fort Pierre National Grassland a good place to look, nest from late May into July. In the Black Hills, the western tanager is most often found in conifer forest, and its nesting season is June and July, so May is mostly about migrants passing through.

Where do piping plovers and least terns nest in South Dakota in May?

• Piping plovers and the sandbar signs

  Nesting begins in early May, says the Park Service · Missouri National Recreational River, below Gavins Point Dam, and North Alabama Bend near Vermilion

  The National Park Service says plovers are on their Missouri River breeding grounds from April through August and that nesting begins in early May, with three or four eggs that hatch in about 28 days. South Dakota Birds and Birding calls the piping plover an uncommon summer breeding resident and says most of the state’s birds are below Gavins Point Dam in the far southeast, with North Alabama Bend, southwest of Vermilion, a good place to look. The Park Service notes that the birds are highly sensitive to people and that nesting areas are posted with black-and-white signs, with warnings at boat ramps and water access points. The practical rule is simple: if you see the signs, stay off that stretch of sand, keep dogs leashed and watch from the water at a distance.

• Least terns, a local specialty

  Nesting runs May through July · Missouri River sandbars along the Nebraska border

  South Dakota Birds and Birding describes the least tern as an uncommon and local summer resident that breeds on Missouri River sandbars, mostly on the lower river along the Nebraska border, where the free-flowing stretch below Gavins Point Dam still has wide sandbars. Nesting runs from May through July, and the site says dams have submerged much of the habitat and that water regulation can cause nesting failures. If you want to see a tern, bring a spotting scope and look for a small, fast bird with a yellow bill hovering over a side channel.

What young animals can you see in South Dakota in May?

• Prairie dog pups above ground

  May to early June, per the Park Service · Badlands, Wind Cave, Lacreek and the national grasslands

  The Park Service says black-tailed prairie dogs breed in March and April, with young born four to five weeks later in litters of two to eight, and that from May to early June the pups begin leaving their burrows. A pup’s first days above ground look like a game of peek-a-boo, with a head at the burrow mouth and a retreat at the first alarm call. A warning cry sends neighbors diving into their burrows, and predators the Park Service lists include coyotes, bobcats, eagles, hawks and badgers. Sit in a car or on a camp chair a good distance from a town and the colony will resume its business within minutes.

• Burrowing owls and black-footed ferret kits

  May and June · Prairie dog towns in western South Dakota

  South Dakota Birds and Birding says burrowing owls nest in prairie dog burrows from May through July and that the species is uncommon to common in western South Dakota in summer; the Fort Pierre and Buffalo Gap National Grasslands both have extensive prairie dog towns. The black-footed ferret, which depends on prairie dogs for about 90 percent of its diet, mates in March and April, and with a gestation of 41 to 43 days the kits arrive around May. Newborn kits are blind and stay underground until about two months old, according to the Park Service, so the chance that a visitor sees one in May is very small. Badlands National Park puts the park’s ferret population at about 120, about 80 of them in the Conata Basin area.

• Bison calves at Wind Cave and Custer

  Generally April or May · Wind Cave National Park, Custer State Park and the Badlands

  The Park Service says bison calves at Wind Cave are generally born in April or May, and that this is also the season when the animals rub off their winter coats on signs, fence posts and trees. The same page tells visitors to keep 25 yards or more between themselves and a bison and warns that raised tails, bluff charges, pawing and snorting mean the animal has had enough. Custer State Park’s rule is to stay in the vehicle or keep 100 yards away from bison and elk. The two numbers come from two different parks, so follow what is posted where you are and lean toward the larger one.

• Bats are back in the Hills

  Warm evenings from May · Jewel Cave and Wind Cave areas of the southern Black Hills

  The Park Service says hoary bats, silver-haired bats and eastern red bats are summer residents of Jewel Cave National Monument, and that seven other bat species use the cave all year. The monument’s historic entrance is closed to entry from October through May to protect hibernating bats. Its midwinter count in 2023 and 2024 found 602 bats, 831 fewer than in 2018, and the Park Service says it does not know why, possibly white-nose syndrome or movement within the cave. The page gives no return dates, so I have none to offer. Look at dusk for dark shapes over a parking lot or a pond, and if one lands in your home, call the park or GFP before you try to move it.

• Mountain goats, bighorns and fawns

  Young appear from late spring · Black Hills granite and Badlands buttes; deer everywhere

  Game, Fish and Parks describes the Black Hills mountain goats as an introduced population present since the 1920s, living on granite outcrops between 4,000 and 7,242 feet in a range that runs from Highway 385 near Crazy Horse to Mount Rushmore and south of Harney Peak toward the Needles. The Badlands has about 250 bighorn, according to the Park Service, which also pictures a ewe with two lambs on a butte. The agencies we read do not give birth dates for kids, lambs or fawns, so treat the late-spring timing as general. Whatever the species, the sound advice for a young animal alone is to leave it: a still fawn in the grass has typically been left there on purpose while the doe feeds elsewhere. Take your photograph from where you stand and walk on. For a real injury, call Game, Fish and Parks at 605-223-7660.

What blooms in the Black Hills and on the prairie in May?

• The Black Hills spring group

  Spring into early summer, with varied timing by elevation · Open pine forest, meadows and limestone slopes in the Hills

  The Forest Service lists a spring-to-early-summer group that includes arrowleaf balsamroot, with large arrow-shaped leaves and big yellow flowers on higher limestone slopes in the west and northwest Hills, darkthroat shootingstar, with nodding purple flowers and a sweet, clove-like scent, early cinquefoil, goldenpea, heartleaf arnica and Rocky Mountain iris, whose large light-purple flowers grow in moist meadows and open forests. Kinnikinnik, a mat-forming evergreen, carries white to pink urn-shaped flowers, and the star lily puts out white flowers at ground level on prairie and open pine ground. The page does not give bloom months for each plant, so a walk at the end of May will find more open flowers than one at the start.

• Pasque flowers have gone to seed

  May · Prairie hillsides and open pine forest

  In the Forest Service’s words, the pasque flower is among the first flowers of early spring. By May, expect to find some plants already turning to seed, with later bloom on cooler slopes higher in the Hills. If you photographed the flower in March or April, May is the month for the same-place-twice page of a field journal: return to the spot and see what has changed.

Which toads and frogs call in South Dakota in May?

• Northern leopard frog

  Mid-May through June · Dugouts, wetlands, reservoirs and oxbow lakes

  The state amphibian and reptile site says northern leopard frogs mainly breed from mid-May through June. The call is a drawn-out rattling snore lasting three seconds or more, followed by several grunts or chuckles, and in a mixed chorus the boreal chorus frog can drown it out. On wet, humid nights the frogs may travel into upland areas, so you may meet one on a gravel road.

• American toad

  May to June · Semi-permanent wetlands, lakes and reservoirs

  American toads breed from May to June, usually arriving at wetlands after the chorus frogs have come. The male gives a melodic trill lasting 5 to 30 seconds. After breeding, adults move to upland prairie.

• Great Plains toad and plains spadefoot

  Triggered by heavy rain · Temporary pools in fields and grassland

  Great Plains toads breed from late May through July, but the state site says heavy rainfall mainly determines the timing, with adults moving to temporary wetlands during or just after the storm and breeding intensely for only a day or two. The call is a long, pulsing, metallic trill lasting about 10 to 50 seconds. The plains spadefoot is another explosive breeder, triggered by heavy rain, whose chorus lasts one or two nights; its call is a wail or snore-like bleat. Neither will wait for the weekend, so if a thunderstorm drops a couple of inches on a pasture, go out with a flashlight afterward.

• Tiger salamander larvae and painted turtles

  May · Fishless ponds, wetlands and prairie dog burrows

  The state site says adult tiger salamanders are active from April through September, breed in early spring in wetlands without large fish, and often use abandoned prairie dog burrows; the gilled larvae grow through summer. The painted turtle, the state’s most common turtle, mostly breeds from early May to June, with eggs laid in June and July in sandy soil, sometimes along dirt roads, so slow down near water in the coming weeks.

What is the paddlefish season on the Missouri River?

• Paddlefish snagging on Lake Francis Case

  May, by limited license · Lake Francis Case on the Missouri River

  Game, Fish and Parks says a limited number of licenses are available, to residents only, to snag a paddlefish on Lake Francis Case during May. A second season, with licenses for residents and nonresidents, runs in October below Gavins Point Dam. The page does not list 2027 dates or say which year its season information covers, so call the agency (605-223-7660) or write to WildInfo@state.sd.us before you plan. Whether or not you fish, the season is a reminder that the big reservoirs hold more than walleye.

What is May weather like in South Dakota?

When is the last spring freeze in South Dakota?

How much daylight does South Dakota gain in May?

What can you see in the South Dakota night sky in May 2027?

• The Eta Aquariid meteor shower, an excellent year

  Best mornings Wednesday, May 5 to Friday, May 7, before dawn · Anywhere with a dark, open eastern sky

  Meteors fall from late April into late May, with the maximum expected between the nights of May 5 and 6. A new Moon on the 6th means a black sky with no glare. Even in the southern states the rate is modest, perhaps ten to thirty meteors an hour in the final stretch of darkness, and the new Moon makes it an excellent year for the shower. The shower’s radiant, in the constellation Aquarius, does not climb into view until about one to two hours before dawn at northern latitudes, so the farther north you are, the fewer meteors you will see. In South Dakota, expect fewer than the figures quoted for the southern two-thirds of the country. Dress warmly, face east, lie back on a chair and give it an hour before sunrise. Our cloud guide helps with deciding whether to get up at all.

• The Flower Moon, and a seasonal Blue Moon

  Full at 5:59 a.m. CDT (4:59 a.m. MDT) on Thursday, May 20; best evening Wednesday, May 19 · Any horizon with a clear view to the east

  The Moon becomes full in the predawn hours of the 20th, so the evening of Wednesday the 19th is the one to choose, with the Moon rising about the time of sunset, a little after 8 p.m. Check a moonrise table for your town, since the exact time depends on where you stand. An older almanac rule names the third of a season’s four full moons the Blue Moon, and astronomical spring this year holds four, with dates in late March, mid-April, mid-May and mid-June, so this Flower Moon counts as a seasonal Blue Moon. Under the newer rule of two full moons within one calendar month, 2027 has none. Flower Moon is the name most people know, and the Blue Moon label is the older seasonal one. Our moon phases guide covers the rest of the year.

• Mercury at its best evening of the year

  Look for it low in the west-northwest from roughly May 12 to June 5; greatest eastern elongation on May 28 · Open western horizon, 45 to 90 minutes after sunset

  The planet’s widest angle to the east of the Sun comes on Friday, May 28, at about 23 degrees, so the 27th and 28th both rank among its best evenings. Of the year’s evening appearances, this is the best placed for northern states. At 40 degrees north, our calculations put it setting about 97 minutes after the Sun in mid-May, at about magnitude -0.6, and about 105 minutes after the Sun on June 1, though it fades quickly through mid-June. South Dakota is a few degrees north of that latitude, so the numbers are a guide and not a promise. Choose a spot with nothing blocking the west, wait for the deep blue of late twilight, and use binoculars to confirm what you see.

• Venus and Saturn, a tough pairing

  Friday, May 7 and the mornings around it · Flat eastern horizon before sunrise

  Early on Friday, May 7, Venus and Saturn lie in Pisces roughly half a degree to one degree from each other, with their closest approach coming later that day while the Sun is up. Venus is just one hour or so ahead of the Sun, so at 40 degrees north both sit only a few degrees above the horizon thirty minutes ahead of sunrise. It is a binocular sight over a clear horizon and not an easy one, and it is worth a try only if you are already up for the Eta Aquariids. Venus shines at about magnitude -3.9, with Saturn near +0.7.

• Jupiter and Mars in the evening

  All month · South and southwest after dusk

  Our calculations have Jupiter setting about seven hours after sundown on May 1, and Mars near 2 a.m., so both are high in the south as the sky darkens and both are slowly dimming. On the 12th the first-quarter Moon sits beside Jupiter, about 1.2 degrees from it at closest in the afternoon, so the evening of the 12th is the night to look. The Moon is near Mars, about three degrees from it, on the 13th. Our calculations give these pairings, so treat the times as a guide. These are the nights to pick out the planets beside a bright Moon.

• Dark skies, the Milky Way and the Badlands

  Best around the May 6 new moon, and again from May 25 · Badlands National Park and any dark-sky site

  For a Moonless dark sky with the Milky Way’s core above the horizon, the early and late parts of the month work best, by our own calculations: at 40 degrees north the usable stretch is the first two weeks and the last week, with up to roughly four hours of darkness, while at 48 degrees north it shrinks to under two hours on a handful of nights because the nights are so short. South Dakota lies between the two. The Park Service says Badlands National Park runs telescope-assisted night sky viewings at the Cedar Pass Amphitheater each evening from Memorial Day through Labor Day, starting around 9:45 p.m. in the first months of summer, with the Milky Way described as especially phenomenal. Memorial Day in 2027 is May 31, and the page gives no 2027 dates, so confirm with the Ben Reifel Visitor Center. Geomagnetic storms favor the weeks around the equinoxes more than May, and no agency predicts them months ahead, so check NOAA’s aurora outlook on the night.

What can South Dakota families do outdoors in May 2027?

• Join the City Nature Challenge identification weeks

  Observations April 30 to May 3, 2027; identification May 4 to 16 · Wherever you live, with the iNaturalist app

  Photographs for the 2027 contest are taken from April 30 to May 3, then volunteers name what is in them from May 4 to 16, and the organizers post results on May 20. Participation is by city region, and the site does not show whether a South Dakota area is in, so look before you plan; the iNaturalist app is handy for your own list either way.

• Report spring arrivals

  All month · Home, school yard or the nearest park

  Journey North, which follows hummingbirds, monarchs and other travelers across the continent, takes sighting reports online. Log your first oriole, first hummingbird, first toad trill and the day the pasque flower went to seed. Share the date, never a nest location.

• Go to a refuge early

  Morning · Lake Andes, Sand Lake, Lacreek

  Lake Andes National Wildlife Refuge covers 5,639 acres, including a 4,700-acre lake, and the Fish and Wildlife Service says waterbirds and songbirds nest there in great numbers and shorebirds gather in large flocks during migration. Sand Lake, 21,498 acres on the Central Flyway, has more than 266 bird species recorded and more than 123 that nest there. Roads are gravel and can be impassable after a rain, so call ahead.

• Mark Memorial Day weekend with a field walk

  Saturday, May 29 to Monday, May 31 · Any park

  The holiday lands on the last Monday of the month, May 31, in 2027. Take a notebook to a cemetery or park, where old trees and open grass draw birds, and let children practice waiting and looking.

Safety notes for May in South Dakota

• Spring turkey season

  Usually through May 31, check the 2027 rule · Prairie units and Black Hills

  The commission’s last published rule was written for 2025 and 2026. In 2026, prairie units with one season ran from April 11 through May 31, the Black Hills and archery season ran from April 25 through May 31, and the late half of the split prairie units ran May 1 to 31. The rule limits the weapons that may be used, forbids shooting a bird that is on a roost or in a tree, and allows hunting only between thirty minutes before sunrise and sunset. The 2026 application sheet says state parks and recreation areas are closed to hunting after April 30 unless the unit description says otherwise. We found no published 2027 dates, so check the commission’s current rule and the GFP turkey page for 2027, and ask about any orange requirement. If you walk in turkey country in May, wear bright colors and never imitate a gobble.

• Ticks and mosquitoes

  From spring on · Tall grass, forest and water edges

  South Dakota State University Extension names the American dog tick, the Rocky Mountain wood tick and the blacklegged tick, which can carry Lyme disease and anaplasmosis, and says ticks are most abundant in tall grass, forested areas and near water. Wear long pants and socks, use a repellent labeled for ticks, treat clothing with permethrin, and check yourself afterward. Remove an embedded tick with fine tweezers as close to the skin as you can.

• Rattlesnakes

  Warm days · Grassland, rocky outcrops and prairie dog towns, mostly West River

  The state amphibian and reptile site says the prairie rattlesnake is the only South Dakota snake dangerous to people and that it is abundant in the west and along the Missouri River, living in grasslands near rocky outcrops and prairie dog towns. It is hard to see when still. Look before you step or reach, especially among rocks, and carry a light at dusk.

• Bison, mothers with young and wet roads

  All month · Parks, refuges and gravel roads

  Bison with calves are not animals to test, so keep to the distances the parks give above. Gravel and grassland roads can become impassable after storms, and creek crossings can rise fast, so do not drive through water you cannot see the bottom of.