What to look for in nature in Connecticut this May

Which birds are passing through Connecticut in May, and where can you see them?

• The warbler wave

  Roughly the first three weeks of May, with the heaviest numbers around the middle of the month · Woodland edges, shrubby thickets, park trees and shoreline stopovers across the state

  New England magazine singles out the Blackburnian warbler as a typical May arrival, a bird that stays high in the treetops and gives a thin, high song that ends in a trill. It adds that yellow-rumped warblers can be abundant at the peak. Connecticut Audubon says yellow warblers are among the commonest warblers of the month, which is why they land on nearly every list from its Birdathon. The trick with warblers is to look up, since many feed in the new leaves at the tops of oaks, and to learn a few songs before you go.

• Hammonasset and Birdcraft: where migrants pile up

  Mid-May is the high point; mornings after a night of southerly wind are usually best · Hammonasset Beach State Park in Madison; Birdcraft Sanctuary in Fairfield

  Patrick Comins of Connecticut Audubon says migrants flying overhead easily spot a coastal park like Hammonasset, which makes it a good place for them to rest. Birdcraft, a six-acre sanctuary hemmed in by development, packs the birds into a small space where they are easy to find. Hammonasset is the most visited state park in Connecticut, with more than three million visitors a year according to Audubon, so go early on a weekday if you can.

• Sparrows, loons and the nighthawk watch

  White-crowned sparrows peak around Mother’s Day (Sunday, May 9, 2027); loons pass through until about mid-May; nighthawks appear in mid-May · Brushy fields and yard edges; larger ponds after rain; the open sky in late afternoon

  The same New England magazine article says white-crowned sparrows reach their peak numbers in Connecticut around Mother’s Day, and that common loons pass over the south of the state from late March to about mid-May. Check the bigger ponds after a spring rainstorm for loons, grebes and sea ducks that dropped in overnight. In mid-May, look skyward in the late afternoon for common nighthawks and listen for their buzzy calls.

• Hummingbirds and orioles at the feeder

  Hummingbirds are already arriving by May; orioles tend to turn up about the same time · Gardens with early flowers, clean feeders and oranges or jelly for orioles

  Journey North, the citizen-science project that maps migration, reported in 2020 that Baltimore orioles were arriving at about the same time as ruby-throated hummingbirds, and some observers saw both on the same day. Those notes were not from Connecticut, so add your own first sightings to the Journey North maps. Our April page covers the first hummingbird sightings; a wild red columbine in bloom is a natural stop for one, as the plants section below explains.

• Migration Magic and the Birdathon

  A month-long festival in May; the 2027 schedule is not posted yet · Events across the state, and any park or yard you like for the Birdathon

  In 2026 Connecticut Audubon held Migration Magic from May 1 to May 31, with a guided walk at Birdcraft on May 5, a free introduction to birding on May 9, a bird-banding demonstration on May 23 and a family craft day on May 30. The Birdathon is a month-long contest to see or hear as many species as you can in Connecticut and a designated corner of New York, with the proceeds going to conservation. The festival page says to check back for 2027 details, so treat those 2026 dates as a sample of what the month usually holds, not as a schedule. World Migratory Bird Day fell on May 9 in 2026, and its organizers had not announced the 2027 date when we looked.

What is happening on Long Island Sound and the rivers in May?

• Horseshoe crabs spawning

  May and June, mostly around high tide; the new moon on May 6 and full moon on May 20 are traditional peaks, though New England spawning follows water temperature too · Sandy beaches of Long Island Sound; Milford Point in Milford is a long-studied site

  Horseshoe crabs come ashore to mate on high tides in late spring and early summer. The Atlantic States Marine Fisheries Commission says spawning generally runs from March through July, with peak activity after sunset on new and full moon high tides in May and June, but that in some areas, New England included, spawning follows water temperature more closely than moon phase or time of day. Check a tide table and walk the high-tide line slowly in the evening. A mature female can lay many thousands of eggs, which is why crowded beaches matter to the birds and fish that feed on them.

  Project Limulus, run from Sacred Heart University, tags crabs at Milford Point and on other Sound beaches with the help of volunteers, and its researchers mark nests with pink flags. If you find a tagged crab, you can report the tag at fws.gov/crabtag. A law signed in August 2023 bans hand harvesting of horseshoe crabs, with exemptions for scientific and medical use and a $25 fine per crab taken. A Project Limulus director has said recovery will take time and depends on what neighboring states do. If a crab is stranded on its back, hold it by both sides of the shell, never by the tail, which can injure it.

• American shad in the upper river

  Shad reach the Holyoke fishway, just over the Massachusetts line, in late April or early May · The Connecticut River; the best fishing and watching is upstream of Hartford

  Holyoke Gas and Electric, which runs the fishway at the Holyoke dam, says shad swim into the river from late March on and reach Holyoke in late April or early May, in water between 54 and 68 degrees Fahrenheit. After spawning they drift back downstream, mostly in daylight in June and July. DEEP’s assessment page says adult returns have fallen in recent years, which it links to the big increase in striped bass along the coast, and expects abundance to rise and fall over time. We found no published forecast for 2027.

• Trout stocking and a free fishing day

  The 2026 free fishing day was Saturday, May 9; DEEP lists no 2027 date yet · Statewide, including the 15 Trout Parks

  For the 2026 season DEEP held a Free Fishing Day on Saturday, May 9, when no fishing license was needed, and two more days, June 21 and August 8, when anglers 16 and older needed a free one-day license. DEEP lists no 2027 dates, so check its licensing page in spring. Children under 16 fish free all year.

Which shorebirds, ospreys and martins are nesting on the Connecticut coast in May?

• Piping plover and least tern chicks

  By that arithmetic, hatching begins in late May; DEEP gives April through August as the nesting season · Fenced sections of beaches, including Milford Point and Hammonasset

  Both plover parents sit on the eggs for about 27 days, according to DEEP’s fact sheet. The chicks run from the nest within hours and do not fly until about 28 days. The state marks nesting habitat each spring with stakes, twine and signs, and on some beaches protects nests with wire cages that come off once the chicks hatch. A 2026 DEEP release notes that both species are state threatened and that plovers are also federally threatened. It asks beachgoers to keep pets, bicycles and vehicles at least 25 feet from the marked areas, says dogs are banned at many beaches during the season, and singles out Memorial Day weekend as a time of heavy use. Chicks wander outside the fencing, so look down before you step. DEEP also warns against kites and drones near a nesting beach, since the birds read them as predators.

• Osprey chicks

  Eggs laid in April hatch around May; young first fly roughly two months later · Platforms, channel markers and poles along the coast and big rivers

  DEEP’s osprey sheet gives an average of three eggs and about a month of incubation, so chicks in a platform nest are likely to appear in May. The sheet asks people and pets to stay at least 300 feet from a nest, adding that disturbing ospreys is prohibited under the federal Migratory Bird Treaty Act and under state law. Adults can become aggressive when approached, which is a sign you are too close.

• Purple martin colonies

  Eggs take 15 to 18 days to hatch and young stay in the nest 24 to 28 days, so late May and June are busy · Houses and gourds near the shore and open fields

  In Connecticut, DEEP notes, purple martins nest only in man-made houses or hollow gourds, usually 12 to 15 feet up and painted white. The Wildlife Division is trying to document every colony, and landlords who host one are asked to report it. Banded martins can also be reported through the Wildlife Division’s colony monitoring program.

Which frogs, toads and turtles are active in Connecticut in May?

• Toads and treefrogs at the pond edge

  Spring peepers fade by the end of April; American toads breed in late April; gray treefrogs breed from late spring into July · Wooded ponds, swamps, marshes, and sandy or gravelly shores for Fowler’s toads

  A UConn herpetology lecture has the spring peeper calling from the first warm spring night to roughly the close of April, the American toad breeding in a rush in temporary pools in late April, and gray treefrogs leaving the treetops through April and May to breed in June and July. On a warm, damp night in the second half of May, stand at a pond edge and listen for what is left of the toad trills and the first treefrog calls, and check DEEP’s frog and toad call guide to sort them out.

• Snapping turtles on the move

  Nesting is described as May through June in a 2024 DEEP interview and as May through July on DEEP’s turtle page · Sandy, sunny ground near ponds, streams and wetlands, including roadsides and gardens

  A DEEP wildlife biologist told Connecticut Public in 2024 that females leave the water to look for sunny, sandy soil. Snapping turtles can top a foot in length and need a decade or more to mature, so each adult lost on a road costs a local population for years. DEEP says turtles crossing roads in June and July are often pregnant females and advises helping them along rather than collecting them. Help only when it is safe, point the turtle the way it was already heading and never carry it far. Lift a snapping turtle by the back of the shell, not the tail, or nudge it along with a shovel. A turtle laying eggs should be left alone to finish.

• Painted and box turtles

  Nesting season runs May through July; hatchlings emerge in early fall · Soft soil near ponds and in woodland edges

  Connecticut has eight native freshwater and land turtles, and nine of its 12 native species, sea turtles included, are on the state’s list of endangered, threatened and special concern species. Leave wild turtles where they are, never keep them as pets and never release captive turtles into the wild. If a turtle has nested in a busy spot, DEEP suggests covering the site with a marker such as a traffic cone, then removing any cover after a short time because shade changes the temperature of the eggs. Do not put a box turtle in water.

What young animals and night creatures are out in Connecticut in May?

• White-tailed deer fawns

  DEEP’s release says births run from May to late June; its deer fact sheet says usually June · Fields, forest edges, backyards and roadsides

  The two DEEP pages differ slightly on timing, so expect the first fawns late in May and most in June. Fawns weigh 4 to 8 pounds at birth, and twins are common in Connecticut. DEEP says a doe visits her fawn only three or four times a day, for about 15 minutes each time, to avoid drawing predators. A newborn freezes and lies still if approached. DEEP’s advice is to leave a found fawn for at least 48 hours, keep people and pets away, and call only if it wanders and cries for hours or looks injured. Removing a healthy fawn is illegal.

• Black bears and their cubs

  Cubs were born in the den in December or January; mating happens in late spring and early summer · Mostly the northwest quarter of the state, spreading east

  DEEP puts the resident population at about 1,200 bears, including juveniles, and says it is growing. Litters are usually two or three cubs that stay with the mother until their second spring, which is why yearlings are now striking out on their own. Wetland plants are among the few spring foods. Where bears visit, skip the bird feeders, and take one down at once if a bear shows up. On a meeting, shout, wave your arms and back away slowly, with dogs leashed and no running. Mother bears often leave cubs alone or send them up a tree, so call the Wildlife Division rather than moving them.

• Fox kits and rabbit nests

  Kits play at den sites in spring and early summer; young cottontails leave their nests in 2 to 3 weeks · Yards, field edges and stone walls

  Kits playing outside a den are normal, according to DEEP, and orphaning is rare because both parents raise them. Do not feed or approach them. A mother rabbit visits her nest only briefly, at dawn and dusk, so a nest that seems unattended is not abandoned. Keep pets and mowers away. Fully feathered young birds on the ground are usually fledglings still tended by their parents.

• Bats

  Report summer colonies to DEEP · Barns, eaves, bat houses, and the air over ponds at dusk

  DEEP lists nine bat species in Connecticut: six cave bats and three tree-roosting bats. White-nose syndrome has killed nearly seven million cave bats in North America since 2006, and DEEP says little brown and northern long-eared bats have declined by more than 90 percent in the region. Tree-roosting bats are considered safe from the disease. If you have bats in a building, report the colony; never handle a live bat.

• The first fireflies

  Late May through July, with a peak from mid-June to mid-July · Meadows, lawns and woodland edges on warm, humid evenings

  One local guide, in the Newtown Bee, gives late May as the usual start and says a warm, humid spring can bring them out sooner; treat the dates as rough. Connecticut entomologist Gale Ridge links declines in built-up areas to city lighting that interferes with their flashing. The guide suggests leaving fall leaf litter, skipping pesticides and turning off outdoor lights.

What blooms in Connecticut in May, and when does the state flower open?

• Woodland ephemerals in the Northwest Hills

  Mostly through May in Norfolk, per a local writer · Barbour Woods and Great Mountain Forest near Norfolk

  A Norfolk writer lists five spring ephemerals that bloom there mostly in May: bloodroot, yellow trout lily, jack-in-the-pulpit, red trillium and wild red columbine. Red trillium smells unpleasant, and the writer warns that bloodroot and columbine are toxic, so enjoy them by looking. Columbine’s downward-hanging flowers are pollinated most often by hummingbirds. Stay on the trail to protect next year’s shoots.

• Mountain laurel, the state flower

  Buds swell in May; flowers usually open from late May and mostly in early June, per UConn · Rocky woods, hillsides and roadsides, along Interstate 95 and throughout the state

  The General Assembly designated mountain laurel the state flower in 1907, and the state’s own page calls it perhaps the most beautiful of native American shrubs. The UConn Plant Database says it blooms in late May and mostly in early June, and that the flowers last two weeks or more. Native Plant Trust describes a multi-stemmed shrub with leathery, evergreen leaves and clusters of white or pink flowers. Every part of the plant is poisonous, so look but do not eat or chew it. In May, look for the bud clusters.

How much daylight does Connecticut gain in May?

When is the last spring freeze in Connecticut?

How warm is May in Connecticut, and what weather should you watch?

What can you see in Connecticut’s night sky in May 2027?

• The Eta Aquariid meteors

  Best before dawn on May 5, 6 and 7 · Look anywhere dark, toward the east before dawn

  The shower is active from about April 19 to May 28, and the new moon on May 6 leaves it moonless. At Hartford, per the Naval Observatory, civil twilight begins about 5:10 a.m. on the 7th and the Moon is a thin sliver that rises at 4:46 a.m. on the 5th and 5:58 a.m. on the 7th. Sea and Sky says the shower can produce up to 60 an hour at its peak. In New England expect noticeably fewer, because the radiant in Aquarius climbs only an hour or two before sunrise at our latitude. Lie back, give your eyes 20 minutes and watch the eastern half of the sky.

• Venus and Saturn at dawn

  The morning of May 7, with the mornings before and after nearly as good · Very low in the east before sunrise

  By our own calculation the two come within about 0.6 degrees of each other on May 7 and remain about a degree apart on the mornings before and after. Venus is brilliant, around magnitude minus 3.9; Saturn is far fainter at about plus 0.7. Both sit only a few degrees up half an hour before the 5:40 a.m. sunrise at Hartford, so you need a clear eastern horizon and binoculars. It is a hard sight, not an easy one.

• The Flower Moon, a seasonal Blue Moon

  Full at 6:59 a.m. EDT, Thursday, May 20 · Rising in the east just before sunset on the evening of May 19

  Full arrives after the Moon has set, so watch on the evening of May 19. At Hartford the Moon rises at 7:51 p.m., 17 minutes before sunset, already 99 percent lit. The next evening it rises at 8:56 p.m. It earns the Blue Moon name under the seasonal rule, which counts four full moons in a season and gives the label to the third. This spring has four, ending with June 18 in local time. By the modern calendar-month rule 2027 has no Blue Moon at all, and Sea and Sky uses the seasonal count.

• Jupiter and the Moon, then Mercury at dusk

  Moon beside Jupiter on the evening of May 12; Mercury best from about May 12 to June 5, with May 27 and 28 closest to its peak · Jupiter high in the evening sky; Mercury low in the west-northwest after sunset

  On May 12 the half-lit Moon sits beside Jupiter, closest (by our calculation) at 5:52 p.m. EDT, a gap of roughly 1.2 degrees, and the pair stands high in the evening sky. Mercury reaches its widest eastern gap from the Sun, 22.8 degrees, on May 28, and the evenings of May 27 and 28 come closest to that peak. Search the low west-northwest sky between 45 and 90 minutes after sunset, which at Hartford on May 27 (sunset 8:15 p.m.) means roughly 9:00 to 9:45 p.m. It fades quickly in early June.

What can families do outdoors in Connecticut in May?

Safety notes for May in Connecticut