Local Arthropods

 

Ailanthus Webworm Moth (Atteva aurea).  
Rowan County, North Carolina.

We humans like to think we are the most important creatures on Earth.  But scientists have described about 1.5 million species of animals, with many more millions to be discovered.  Mammals, including us, represent about a small fraction of the worlds animals with just over 6500 species.  Most animals are arthropods with about 1 million described species.  According to the numbers, arthropods are the most important animals on the planet.

Arthropods are invertebrates with exoskeletons made of chitin and have jointed legs.  Examples of arthropods are insects, spiders, crustaceans and centipedes.  Arthropods are astonishingly diverse and often strikingly beautiful.  And you don’t have to travel to the tropics to experience this diversity.  Our home state of North Carolina has an amazing array of arthropods.  

Class Insecta includes all the insects, with nearly 1 million described species.  Moths and butterflies are in the Order Lepidoptera, and we love butterflies because of their dazzling colors and variety of forms.  But moths outnumber butterflies 10 to 1. Some call moths the lesser Lepidoptera and it is true that many are small and nondescript, but we do have some striking moths in our area.   

Ailanthus Webworm Moth.
Rowan County, North Carolina.

The Ailanthus Webworm Moth (Atteva aurea) is a tropical species that has colonized much of Eastern North America following the introduction of a host plant, the invasive Tree of Heaven (Ailanthus altissima).  This small moth is brightly colored with orange wings and a pattern of white spots bordered with black. 

Eight-spotted Forester (Alypia octomaculata).
Rowan County, North Carolina. 

Eight-spotted Foresters (Alypia octomaculata) are native North American moths ranging from the US-Canadian border to Florida and west to the Great Plains.  Like most insects, moths have two pairs of wings, and the Eight-spotted Forester has black wings with two white to cream-colored spots per wing, giving it eight spots.  

Saltmarsh Moth (Estigmene acrea).  This is a mating pair with'
the female above and the male below. 
Rowan County, North Carolina. 

Virginia Tiger Moth (Spilosoma virginica).
Rowan County, North Carolina. 

The Salt Marsh Moth’s (Estigmene acrea) name is something of a misnomer as it can be found not just in salt marshes but throughout much of North and Central America, .  These moths have white forewings decorated with black spots and their legs are striped black and white. We found a pair of Salt Marsh Moths mating on the stem of a plant at a local park.  Another white moth in our area is the Virginia Tiger Moth (Spilosoma virginica). This pale species is found across North America.

Male Luna Moth (Actias luna). 
Rowan County, North Carolina. 

The brushy antenna of a male Luna Moth.
Rowan County, North Carolina. 

One of the most dramatic moths in our area is the Luna Moth (Actias luna).  Luna Moths are large with a wingspan of up to 7 inches.  Their wings are pale green and have eye spots on both the fore and hindwings.  The front of the forewings is edged in maroon, and the hindwings have trailing spiral tails.  The eye spots and the tails are defensive adaptations.  The eyes spots fool predators into thinking they have been seen and the tails can be easily shed if the moth is caught by a bird.  Adult Luna Moths live for about a week.  During that brief time, they must find mates and lay eggs on a host plant, usually a deciduous tree.  Female Lunas release a pheromone to attract males. The males have large brushy antennae that can detect minute amounts of the pheromone. This enables the male to fly directly to the female.  Adult Luna Moths do not feed because their mouth parts are not functional.  They must complete their life cycle fueled by reserves accumulated by the caterpillars.  Luna Moths live in eastern parts of the United States and Canada.

Bicolored Striped Sweat Bee (Agapostemon virescens).
Mecklenburg County, North Carolina. 

Bees, wasps and ants are classified in the Order Hymenoptera. Agapostemon virescens, the Bicolored Striped Sweat Bee, is a small brightly colored insect.  Its head and thorax are metallic green, and the abdomen has bold yellow and black stripes.  These small bees nest in the ground and only the females have a stinger, although they are not aggressive. 

Nest of the Paper Wasp (Polistes sp.).
Davidson County, North Carolina. 

Paper Wasps (Polistes sp.) are common in our area.  They are predators that feed on insects and make their hanging nests with an array of hexagonal cells each containing a larval wasp.  To make their paper nest the wasps chew wood and mix it with saliva.  From this macerated wood the wasp forms the nest cells. We found a Paper Wasp nest under the roof of a gazebo that was a perfect hexagon, echoing the shape of the individual cells.    

 

American Green Crab Spider (Misumena oblongus).
Rowan County, North Carolina. 

Spiders are Arthropods in the Class Arachnida, Order Aranea.  Over 50,000 species of spiders have been described in the scientific literature.  One fall afternoon we spotted a bright yellow spider on the bottom of an ornamental sweet potato leaf.  It was a American Green Crab Spider (Misumena oblongus).  Goldenrod Crab Spiders often hunt by sitting on a flower and catch insects as they visit. These spiders can change their color to match the flower and the one we saw had probably crawled from a yellow flower. The yellow spider sitting on the deep purple leaf made a striking photo. 

Arthropods are so diverse I could do hundreds of blogs on them, but I will only write one more.  Stay tuned for Chapter 2 of Local Arthropods.

 

Walking Weymouth Woods

 

Red-cockaded Woodpecker (Dryobates borealis)
at a nest hole in a Longleaf Pine (Pinus palustris).
Weymouth Woods Sandhills Nature Preserve, North Carolina.  

Longleaf Pines (Pinus palustris) tower over drought tolerant plants that grow from the sandy soil. Threatened Red-cockaded Woodpeckers (Dryobates borealis) fly between the trees.  This is the Weymouth Woods Sandhills Nature Preserve, located in Moore County North Carolina.  The Sandhills run along the inland edge of the Coastal Plain from Georgia to Virginia. They are the remains of ancient windblown dunes and sand sheets formed when sea levels were higher than today.  The rainwater drains quickly through the sand creating a home for a unique assemblage of plants and animals.   

Longleaf Pines.
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

Longleaf Pine forest.  The trees have been scorched by fire at their bases.
Weymouth Woods Sandhills Nature Preserve, North Carolina.

Starting down the trail at Weymouth Woods it feels like you are in a park ,with scattered pines and an open understory.  The Longleaf Pine ecosystem is maintained by fire that kills the hardwood trees which would otherwise overtake and replace the pines.  Evidence of fire is found at the base of the pines whose thick, scaly bark keeps the trees from being consumed.

Yellow Wild Indigo (Baptisia tinctoria). 
Weymouth Woods Sandhills Nature Preserve, North Carolina.

Goat's Rue (Tephrosia virginiana).
Weymouth Woods Sandhills Nature Preserve North Carolina.
 

Spurge Nettle (Cnidoscolus stimulosus). 
Weymouth Woods Sandhills Nature Preserve, North Carolina.  

Maryland Meadow Beauty (Rhexia mariana). 
Weymouth Woods Sandhills Nature Preserve, North Carolina.  

Wildflowers abound in Weymouth Woods.  Members of the pea family, the Fabaceae, like Yellow Wild Indigo (Baptisia tinctoria) and Goat’s Rue (Tephrosia virginiana) grow well in the dry Sandhill soil.  Spurge Nettle (Cnidoscolus stimulosus) and Maryland Rhexia (Rhexia mariana) plants flower along the trails.

Rattlesnake Master (Eryngium yuccifolium).
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

Threadleaf Coreopsis (Coreopsis verticillata).
Weymouth Woods Sandhills Nature Preserve, North Carolina.

 

White-topped Aster (Sericocarpus sp.).
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

Composites (family Asteraceae) like the impressive Rattlesnake Master (Eryngium yuccifolium), yellow flowered Threadleaf Coreopsis (Coreopsis vericillata) and the delicate White-topped Aster (Seriococarpus sp.) brighten up the woods. 

James Creek.
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

Sweet Bay Magnolia (Magnolia virginiana).
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

Ebony Jewelwing (Calopteryx maculata).  The white spots
on the tips of the wing show this is a female Ebony Jewelwing. 
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

James Creek trickles through Weymouth Woods and the trail crosses this small stream in several places. The creek supports an array of plants that require more water, like Sweetbay Magnolia (Magnolia virginiana).  Ebony Jewelwings (Calopteryx maculata), brilliant black and blue damselflies flutter in the cool shade.   

Cottonmouth (Agkistridon piscivorus)
swimming across James Creek.
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

The creek also harbors Cottonmouths, also known as Water Moccasins (Akistrodon piscivorus), a venomous pit viper.  In fact, one of the bridges across James Creek is called Moccasin Crossing.  One day Diane and I were hiking along the creek and happened upon one of these snakes.  We jumped back in surprise as the snake slid into the water and swam away. 

This female Eastern Towhee (Piplio erythrophthalmus)
is a member of  the white-eyed subspecies.
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

A brilliant male Summer Tanager (Piranga rubra)
peeking around a branch. 
Weymouth Woods Sandhills Nature Preserve, North Carolina.
 

This Great-crested Flycatcher (Myiarchus crinitus)
was carrying a feather to its nest hole.  
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

Eastern Wood Pewee (Contopus virens).
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

Birds are abundant in the pine forest and along the creek.  White-eyed Eastern Towhees (Pipilo erythrophthalmus) call from the undergrowth.  The Sandhills are the inland limit of this Coastal Plain subspecies's range.  Summer Tanagers (Piranga rubra) give their “pit-i-tuck” call from the trees, Great-crested Flycatchers (Myiarchus crinitus) pop in and out of their nest holes and Eastern Wood Pewees (Contopus virens) sing their plaintive “pee-oh-wee” song as they look for insects. 

Common Nighthawk (Chordeiles minor).
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

Common Nighthawks (Chordeiles minor) usually hunt at night but will sometimes fly during the day.  We were lucky enough to see them perform their impressive aerial mating display.  A male Nighthawk will climb to an impressive height than swoop toward the ground.  As it dives, air passing through wing feathers makes a roar like a speeding racecar.  This is known as booming and is done to attract female Nighthawks and to warn off trespassing males.  

Bachman's Sparrow (Peucaea aestivalis).
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

Bachman’s Sparrows (Peucaea aestivalis) are specialists of the Southeastern pine forests.  They range from Texas to North Carolina and are a near threatened species.  These sparrows will sing from low branches of pines, but they spend much of their time on the ground where they forage and build their nests.  

Red-headed Woodpecker (Melanerpes erythrocephalus).
Weymouth Woods Sandhills Nature Preserve, North Carolina.

Woodpeckers are common in Weymouth Woods including Red-headed Woodpeckers (Melanerpes erythrocephalus).  These bold black, white and red birds light on the tree trunks and chisel out insects.  

 

Red-cockaded Woodpecker.
Weymouth Woods Sandhills Nature Preserve, North Carolina.

Perhaps the most charismatic creature of Weymouth Woods is the Red-cockaded Woodpecker.  About 12,000 of these threatened birds are found in colonies from Virginia to Texas. The Red-cockaded Woodpecker has a black and white ladder back, black cap and a large white cheek patch.  Males have a small red patch of feathers behind the eye, the cockade, that is rarely visible. 

 

Red-cockaded Woodpecker visiting its nest hole. 
Weymouth Woods Sandhills Nature Preserve, North Carolina.

Red-cockaded Woodpecker flying from its nest hole.
Weymouth Woods Sandhills Nature Preserve, North Carolina.

These medium-sized woodpeckers have very specific habitat requirements.  They nest only in mature, living Longleaf Pines that have a fungal infection called red heart disease.  The fungus causes the heartwood of the pine to become soft, making nest excavation easier.  Red-cockaded Woodpeckers drill small holes in the bark of a nest tree that ooze sticky pine sap.  The resinous sap makes it difficult for snakes to climb to the nest hole and eat the baby woodpeckers. This flowing sap also colors the tree trunk white and makes the nest trees easy to spot.  Red-cockaded Woodpeckers are cooperative breeders.  A breeding pair is assisted by their young from pervious nesting seasons who incubate eggs then feed the hatchlings.  The Red-cockaded Woodpeckers are the subject of intensive scientific study and most have colored plastic bands on their legs to allow identification in the field. 

Red-cockaded Woodpecker nest tree.
Dripping sap stains the tree white around the nest hole.
Weymouth Woods Sandhills Nature Preserve, North Carolina. 

Longleaf Pines forests once covered 90,000,000 acres in the Southeast.  The trees can reach 150 feet in height and live for hundreds of years.  Today only about 5% of this forest remains.  Intense economic use of Longleaf Pines began in the 18^th and 19^th centuries. Longleaf Pines were tapped to produce turpentine and resin.  The trees were cut down to make masts for sailing ships and they were milled for lumber.  The coming of railroads in the late 1800s allowed massive clear cutting of the forest and fire suppression let hardwoods replace the pines.  Weymouth Woods gives us a glimpse of the forest that was, with its botanical wonders and fascinating fauna.

Sandhills Longleaf pine forest.
Weymouth Woods Sandhills Nature Preserve, North Carolina.