Sunday, September 9, 2012

GREAT EXPECTATIONS: September in the Piedmont


Birds.− September brings a number of winter residents back to the Piedmont, including the yellow-bellied sapsuckers, an occasional red-breasted nuthatch and a number of wrens (winter, sedge, marsh) and sparrows (swamp and white-throated). Ruby-crowned kinglets, tiny olive-grey birds with bright red spots on their crown, returned to the Piedmont this month after spending the summer in the coniferous forests of Canada and the northern United States. Migrant warblers continue to pass through North Carolina as they head towards the neotropics for the winter. Birders may even see snowy egrets, little blue herons and tricolored herons, which won’t return again to the Piedmont until early April.

Did you know that not all birds need to drink water? Hummingbirds rely on nectar to stay hydrated. Birds in arid areas may not drink at all either (think: ostriches.) Yet, most birds do drink to replenish fluids lost by breathing, excretion through skin and waste production. Some submerge their bills into the water and simply suck it up (e.g., doves). Other birds dip their bills into the water and then point up to the sky, letting the water fall back into their throat. A number of small bird species drink dew-drops.

Butterflies.− This time of year, butterflies are often surprisingly abundant. Look out for the usual suspects, including hackberry emperors gleaning sap from trees, tiger swallowtails puddling to uptake salts and other nutrients, and pearl crescents, whose caterpillars feed almost exclusively on asters.

Expect to see a pulse of cloudless sulphurs, little yellows and sleepy oranges this month. Swallowtail sightings will likely drop-off by mid-month, with the exception of the black swallowtail. Butterfly watchers can also expect to see gray and red-banded hairstreaks, gulf and variegated fritillaries, as well as an increased number of viceroy sightings. Monarchs may be seen as they migrate southward to their winter residence in Mexico.

The Carolinas are home to five families of butterflies: the skippers (Hesperiidae), gossamer wings (Lycaenidae), brush-foots (Nymphalidae), swallowtails (Papilionidae) and the sulphurs and whites (Pieridae). Each of these families can be divided into a number of sub-families, each having distinct identifying characteristics.

This month, we will consider the hairstreaks (subfamily: Theclinae), small and intricately patterned members of the gossamer wing family (Lycaenidae). Hairstreaks are named for the small hair-like tails on the end of each hindwing. These tails resemble antennae and, along with bright eyespots, trick predators into attacking the tips of the wings, rather than the soft body of the butterfly. Males and females usually differ in appearance (i.e., they are sexually dimorphic), but both sexes fly erratically and perch with their wings held together while moving their hindwings up and down.  Gray hairstreaks (Strymon melinus), the most widely and commonly seen hairstreak in North Carolina, is particularly abundant in September. They are blue-gray below, with bright orange spots and a dark tail with a white tip. Gray hairstreaks prefer open sites, and larvae feed on partridge pea, vetch, clovers and other legumes.

Reptiles & Amphibians.− Continue to keep an eye out for snakes and turtles, especially baby box turtles. Skinks and toads are also out in abundance. Although you may still hear frogs and toads calling this month, large choruses won’t start up again until January.

Other Insects.− This month, expect an increase in praying mantis and spider activity. Praying mantises will exude their eggs in a frothy, hardened mass called an ootheca in September.  Meanwhile, female garden spiders (Argiope aurantia) will be guarding egg cases.

In Bloom this Month.− Be on the lookout for some striking September flowers:

In Bloom:
WINGSTEM – Actinomeris alternifolia
WHITE SNAKEROOT – Ageratina altissima
PARTRIDGE PEA – Chamaechrista fasciculata
TURTLEHEAD – Chelone glabra
BEECHDROPS – Epifagus virginiana
DEVIL'S-GRANDMOTHER - Elephantopus tomentosus
BONESET – Eupatorium perfoliatum
BLACK-EYED SUSAN – Rudbeckia sp.
TRAILING WILD BEAN - Strophostyles helvula
GREAT LOBELIA – Lobelia siphilitica
DOWNY LOBELIA – Lobelia puberula
SMALL SKULLCAP – Scutellaria parvula
AXILLARY GOLDENROD – Solidago caesia
GOLDENROD(S) – Solidago spp.

In Fruit:
PERSIMMON – Diospyros virginiana
HEARTS-A-BUSTIN’ – Euonymus americanus
MUSCADINES – Vitis rotundifolia

Wildlife Profile.− This month’s wildlife profile is the COPPERHEAD (Agkistrodon contortrix), the most widespread of North Carolina’s six venomous snakes. The copperhead probably occurs in every county in North Carolina, and is distributed throughout the southeastern United States. Known as “highland moccasins,” copperheads inhabit wooded areas ranging from riparian habitat to ridgetops. They sometimes reside in more open habitat and are fairly tolerant of human development, often frequenting trash piles and abandoned buildings.

The copperhead is a stout, moderately large viperid than can attain a maximum length of almost 4.5 feet. Adults are pinkish-brown with darker, brownish hourglass-shaped crossbands. Neonates, or newborns, have bright greenish-yellow tail tips. They mate in both spring and fall, and give birth to around a dozen live young in September and October. In autumn, copperheads will gather to den communally and with other snake species to better endure the colder months. Normally a quiet, retiring snake, copperheads will strike vigorously if annoyed.

Did you know?
  • Copperheads in the North Carolina Piedmont are intergradations of both northern copperheads (Agkistrodon contortrix mokasen) and southern copperheads (Agkistrodon contortrix contortrix).
  • Vipers are identified by their triangular heads and vertical pupils; Colubrids, non-venomous snakes, have circular pupils.
  • Copperheads in North Carolina eat cicadas, caterpillars, frogs, toads, birds, mice, shrews, voles, lizards, hatchling box turtles, ringneck snakes and worm snakes.

National Audobon Society. 1980. Field Guide to North American Insects and Spiders. New York, New York: Chanticleer Press.
Conant, R., and J.T. Collins. 1991. A Field Guide to Reptiles and Amphibians: Eastern and Central North America. Houghton Mifflin Company: Boston, MA.
Cook, Dave. 2001. The Piedmont Almanac. Chapel Hill, North Carolina: Mystic Crow Publishing.
Daniels, J. C. 2003. Butterflies of the Carolinas. Cambridge, MN: Adventure Publications, Inc.
Ehrlich, P., D. Dobkin, and D. Wheye (1988). The Birder's Handbook. New York: Simon & Schuster.
LeGrand, H. E. Jr. 2009. Notes on the Butterflies of North Carolina. Available at:
Palmer, W. M. and A. L. Braswell. 1995. Reptiles of North Carolina. Chapel Hill, NC: University of North Carolina Press.

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