Birds
April launches spring migration in earnest, and the next couple of months can bring a steady stream of northbound travelers. Watch for wood-warblers (including Golden-winged, Nashville, Chestnut-sided, Magnolia, Black-throated Blue, Black-throated Green, Bay-breasted, and Blackpoll), along with herons (such as Little Blue Herons, Black-crowned Night-Herons, and Cattle Egrets), thrushes (Veery, Gray-cheeked, and Swainson’s), and sandpipers (Spotted and Solitary). You might also encounter Sora, Virginia Rail, or—if you’re lucky—a rare Glossy Ibis.
At the same time, many species arrive to stay for the summer and breed in the Piedmont. These include Whip-poor-wills, Chimney Swifts, Ruby-throated Hummingbirds, Eastern Wood-Pewees, Acadian Flycatchers, Eastern Kingbirds, Northern Parulas, Prairie Warblers, Summer and Scarlet Tanagers, and Yellow-breasted Chats.
Year-round residents are busy this month too. Carolina Wrens—small, energetic brown birds with upturned tails, pale eyebrows, and curved bills—often hatch in April, and nestlings can be heard boldly chirping from their nests. Pairs typically build nests of twigs, bark, leaves, and grasses in protected cavities, both natural and human-made. Unused grills and back porches can be prime real estate for these adaptable birds. After about two weeks of incubation, the young hatch and noisily demand food from both parents. Carolina Wrens live roughly six years and often mate for life.
Did you know?
Spring migration follows four principal “flyways” in North America. The Atlantic Flyway crosses North Carolina, providing a route from Central America and the West Indies for roughly 150 migratory bird species. With ample food and cover, this largely mountain-free pathway stretches from the Gulf of Mexico through the Carolinas and Virginia to the northeastern United States and into central Canada.
Butterflies
By April, butterfly watchers may begin to find a growing diversity of early-season groups: skippers (such as Zabulon, Dusted, and Pepper-and-salt), duskywings (including Mottled and Zarucco), cloudywings (Southern, Northern, and Confused), satyrs (Gemmed and Carolina), and pearlyeyes (Southern and Northern). Silvery Checkerspots can be found in moist floodplains and sometimes along drier woodland edges, where adults nectar and caterpillars feed on sunflowers (Helianthus) and rosinweeds (Silphium spp.). Look for Red-spotted Purples in hardwood forests and forest edges; adults often feed on tree sap or damp ground, while caterpillars use cherries (Prunus spp.) and other members of the rose family (Rosaceae). Sulphurs and hairstreaks remain in play this month as well, along with Question Marks and Commas. Some of the most spectacular visitors may be Monarchs—and their mimic, the Viceroy.
Swallowtails, a largely tropical family of showy butterflies with distinctive hindwing “tails,” make especially exciting April sightings. Five species occur in Durham County: Spicebush Swallowtail, Pipevine Swallowtail, Black Swallowtail, Zebra Swallowtail, and Eastern Tiger Swallowtail. (Eastern Tiger Swallowtail is also the state butterfly of Delaware, Georgia, South Carolina, and Virginia.) Swallowtails use a wide variety of nectar plants, but caterpillars can be quite particular. Pipevine Swallowtail caterpillars feed exclusively on Aristolochia species, including native Dutchman’s pipe (Aristolochia durior) and Virginia snakeroot (Aristolochia serpentaria). Zebra Swallowtail caterpillars rely on North Carolina’s two native pawpaws—common pawpaw (Asimina triloba) and dwarf pawpaw (Asimina parviflora).
Other insects
April brings the start of a familiar chorus: field crickets calling, crane flies hovering over grasses, and ticks becoming abundant. You may also see dragonflies zipping through the air in search of mosquitoes and other prey. Keep an eye out for darners, a family that includes some of the largest and fastest-flying dragonflies in North America. In Durham County, species include Common Green Darner, Springtime Darner, and Swamp Darner. The Common Green Darner—a roughly three-inch green dragonfly with a brown-and-yellow abdomen in females and a bluish abdomen in males—may be active longer than any other dragonfly in the state, often seen from March through October cruising over open habitat, especially near still water.
Reptiles and amphibians
This month, Northern Cricket Frogs, Eastern Narrow-mouthed Toads, and Cope’s Gray Treefrogs begin calling. American and Fowler’s toads, Spring Peepers, Bullfrogs, Green Frogs, Southern Leopard Frogs, and Eastern Spadefoots may continue to call, while the large choruses of Southeastern Chorus Frogs typically begin winding down.
April frog call guide
Southeastern Chorus Frog: a raspy, rising call—like dragging a thumb over the teeth of a comb
Spring Peeper: a loud, medium-pitched “peeep”
Northern Cricket Frog: clinking like two small metal balls being tapped together
American Toad: a long, musical trill
Fowler’s Toad: a long, slightly nasal, “crabby” trill
Eastern Narrow-mouthed Toad: a buzzy, sheep-like call (shorter and buzzier than a Fowler’s)
Eastern Spadefoot: a crabby, deep “eeeerrrr”
Look in shallow permanent or ephemeral ponds for frog and toad eggs—and sometimes tadpoles. In April, visible eggs can include the long gray-green strings of Fowler’s Toad eggs and globs of gelatinous, black-spotted Cope’s Gray Treefrog eggs. In many years, small, dark American Toad tadpoles also emerge this month.
Also watch for basking Yellow-bellied Sliders and Painted Turtles. Snakes are active as well, so take care not to step on the diminutive and well-camouflaged DeKay’s Brown Snake (Storeria dekayi) along preserve trails. When gardening, keep an eye out for secretive Rough Earthsnakes and Eastern Wormsnakes—among North Carolina’s most commonly encountered small snakes.
In bloom this month
April is a wonderful time to test your tree identification skills. Try identifying trees by bark and buds before they leaf out fully.
In late March and early April, woodland hikers may notice a diminutive plant with three mottled leaves radiating from a central point, topped by a single maroon flower. This is often Little Sweet Betsy (Trillium cuneatum), one of the Piedmont’s common trilliums. This musk-scented woodland gem was once used medicinally (including for gangrene and skin ulcers) and is now a favorite in natural landscaping because it tends to be deer-resistant.
In bloom
Buckeyes (Aesculus spp.)
Windflower (Anemonella thalictroides)
Sweet-shrub (Calycanthus floridus)
Musclewood (Carpinus caroliniana)
Flowering Dogwood (Cornus florida)
Rattlesnake-weed (Hieracium venosum)
Quaker-ladies (Houstonia caerulea)
Eastern Yellow Star-grass (Hypoxis hirsuta)
Dwarf Crested Iris (Iris cristata)
Coral Honeysuckle (Lonicera sempervirens)
Hairy Woodrush (Luzula echinata)
Virginia Pennywort (Obolaria virginiana)
May-apple (Podophyllum peltatum)
Early Saxifrage (Saxifraga virgininiensis)
American Bladdernut (Staphylea trifolia)
Giant Chickweed (Stellaria pubera)
Foamflower (Tiarella cordifolia)
Catesby’s Trillium (Trillium catesbaei)
Little Sweet Betsy (Trillium cuneatum)
Maple-leaf Viburnum (Viburnum acerifolium)
Downy Arrow-wood (Viburnum rafinesquianum)
Soil series of the month
The United States contains over 19,000 soil series—the most specific grouping of soils based on shared history, chemistry, and physical properties. The broadest category is soil order; worldwide, there are only 12 soil orders. North Carolina is home to seven.
A common Ultisol in this region—the quintessential deep red, clay-rich soil of the Piedmont—is the Mayodan soil series. Mayodan soil is typically light gray to yellow-brown in the upper 6–12 inches, then becomes more yellowish-red with depth. It formed from Triassic sediments (shales, sandstones, and mudstones derived from erosion nearly 200 million years ago) and naturally supports oak–hickory forests. Today, more than half of Mayodan soils have been converted to agriculture, especially for corn, soybeans, tobacco, and cotton.
Wildlife profile: Northern Parula (Parula americana)
This month’s wildlife feature is the Northern Parula, a colorful warbler that migrates into the Piedmont in spring and breeds locally. Northern Parulas are small songbirds with blue-gray heads and wings, yellow throats, and a chest banded with black, red, and bright yellow. They also show white crescents above and below the eye and two white wing bars.
Each spring, Northern Parulas arrive largely from the Caribbean, though they also winter in Mexico, Guatemala, and Belize. In the Piedmont, these insectivores move quickly, gleaning leaves and branches high in the canopy—though occasionally they drop to eye level. Because they often forage high in trees, they’re frequently detected by voice: a buzzy, ascending song that ends with a distinct, sharp down-note. They typically breed in bottomland forests and build tiny nests using lichen (or Spanish moss farther south) high in the canopy of oaks, maples, birches, and sycamores, often near branch tips. Nests may be assembled in only a few days, and the same nest site can be used year after year. About two weeks after laying speckled, creamy-white eggs, helpless, unseeing young hatch.
Northern Parula populations appear stable or even increasing, yet there is a notable gap between northern and southern populations. One hypothesis is that habitat change—or air pollution—may contribute. Because air pollution can harm sensitive lichen species, it may reduce the availability of an important nesting material for Northern Parulas.
References
Cook D. 2001. The Piedmont Almanac. Raleigh (NC): Barefoot Press.
Daniels JC. 2003. Butterflies of the Carolinas. Cambridge (MN): Adventure Publications, Inc.
Ehrlich P, Dobkin D, Wheye D. 1988. The Birder’s Handbook. New York (NY): Simon & Schuster.
LeGrand HE Jr. 2009. Notes on the Butterflies of North Carolina.
LeGrand HE Jr, Howard TE Jr. 2011. Notes on the Odonates of North Carolina. 3rd Approximation.
Martof BS, Palmer WM, Bailey JR, Harrison JR. 1980. Amphibians and Reptiles of the Carolinas and Virginia. Chapel Hill (NC): University of North Carolina Press.
Moldenhauer RR, Regelski DJ. 1996. Northern Parula (Parula americana). In: Poole A, Gill F, editors. The Birds of North America, No. 215. Philadelphia (PA): The Academy of Natural Sciences; Washington (DC): The American Ornithologists’ Union.
Sense of Place 