Archive for the Moths Category

ONE SMALL STEP FORTY-TWO YEARS AGO

Posted in Beetles, Butterflies, California, Insects, Moths, Musings on July 20, 2011 by Dr. Art Evans

By Arthur V. Evans

I grew up on the southwestern fringes of the Mojave Desert in Southern California, just a stone’s throw from the land of The Right Stuff. My summers were punctuated by weeklong family camping trips to the mountains and the coast. Dad preferred the rugged lushness of the Sierra Nevada, especially along the waterways that spilled off its eastern slopes down to the desert environs of the Owens Valley below. Mom loved the beach, so we would spend another week camped out at Morro Bay or Pismo Beach, both located along California’s Central Coast.

In July of 1969, we spent a week in the Oceano Campground at Pismo Beach State Park, which just happens to be a well-known overwintering site for monarch butterflies. I can still smell the heavy canvas of our baby blue and olive-drab tents heated by the sun as it burned through the last bits of morning fog. I spent every possible moment exploring the freshwater lagoon, coastal dunes, and beach in search of insects and other invertebrates. California ctenucha moths, Ctenucha rubroscapus flitted about the flowers and grasses sprouting up on the dunes. Several diurnal and non-bioluminescent fireflies, Ellychnia californicarested on the flowers growing among the stinging nettles that lined the shore of  the lagoon. Red admirals, western tiger swallowtails, and a dizzying array of dragonflies flew hither and yon, all seemingly daring me to capture them. And I did just that with my recently acquired homemade insect net fashioned from a broom handle, a heavy wire coat hanger, and a net bag made of cheesecloth.

In those days I kept my insect collection in sturdy cardboard cigar boxes. King Edward Imperials housed my butterflies and moths, while the dragonflies were stored in a White Owl box. A Roi-Tan Panatelas box protected my true bugs, cicadas, grasshoppers, and katydids. All of my beetles were neatly arranged in a box that once held Swisher Sweets and the Dutch Masters box served as a catchall for everything else. I can still smell that pungent aroma of tobacco mingled with mothballs!

Earlier that week, on the morning of 16 July, Apollo 11 had set off on its historic flight to put men on the moon and return them safely to Earth. The astronaut’s first steps on the lunar surface, interspersed with simulations, would be televised early on the evening of Sunday, 20 July. Fortunately, I would have access to a television by then because that was the day we would return home.

The promise of seeing and collecting still more insects AND watching men on the moon on television was pretty heady stuff for a 12 year-old! The night was shaping up to be hot and uncharacteristically humid and promised an excellent night for insect activity. I turned on the mercury vapor street light mounted on the garage wall. Dad had installed the bright blue light partly to illuminate the front of the house, and partly to attract insects for me. I quickly discovered that it was a beacon for nocturnal insects!

My plan for the evening was to dash from the light to the television and back to watch both spectacles unfold. It wasn’t even dark yet when Neil Armstrong opened the hatch of the Lunar Module and slowly descended down the ladder to utter those now-famous words, all captured on fuzzy black and white, yet still quite memorable video. Throughout the evening, between bouts of nighttime bugs, I watched in awe as Armstrong and Edwin “Buzz” Aldrin bounced across the lunar surface to collect samples and conduct experiments. Just a few years later, I had the opportunity to meet Buzz Aldrin and get his autograph after he gave a lecture on his lunar experience at the annual Kern-Antelope Historical Society banquet held in Rosamond, California.

As night descended, thousands of insects of all sorts swarmed to the bright bluish light, zooming around it as if they, too, were satellites orbiting a heavenly body. My eyes, ears, and nose were simultaneously assaulted by the flappings and scratchings of chitinous wings and appendages. Undeterred, I dove into the swarm from time-to-time to scoop up select specimens off the rough stucco wall. Some of the more notable insects that I saw that night included many white-line sphinx moths, several California prionus, and a raft of 10-lined June beetles.

For those who did not experience the Apollo 11 mission as it took place, it is difficult to imagine the nearly global excitement generated by the landing of men on the moon. I was lucky enough see this epic event on television. I still get a little verklempt when I watch the video some 42 years later and will forever remember that warm summer night all those many years ago and its promise and deliverance of new and exciting things here on Earth and beyond.

References on California insects

Evans, A.V. and J.N. Hogue, 2004. Introduction to California Beetles. University of California Press, Berkeley, CA.

Evans, A.V. and J.N. Hogue, 2006. Field Guide to Beetles of California. University of California Press, Berkeley, CA.

Hogue, C.L. 1993. Insects of the Los Angeles Basin. Natural History Museum of Los Angeles County, Los Angeles, CA.

Powell, J.A. and P.A. Opler, 2009. Moths of Western North America. University of California Press, Berkeley, CA.

Powell, J.A. and C.L. Hogue, 1979. California Insects. University of California Press, Berkeley, CA.

For more information on Apollo 11 and its mission see:

http://en.wikipedia.org/wiki/Apollo_11

http://spaceflight.nasa.gov/history/apollo/apollo11/index.html

http://www.lpi.usra.edu/lunar/missions/apollo/apollo_11/

http://history.nasa.gov/ap11ann/kippsphotos/apollo.html

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MEET THE FALL CANKERWORM

Posted in Insects, Moths, Pests on January 19, 2011 by Dr. Art Evans

By Arthur V. Evans

Adult male fall cankerworm, Alsophila pometaria. ©2011, A.V. Evans

During a recent warm spell on the heels of New Year’s Day, a small collection of somberly hued moths gathered at my front porch light. I posted a picture of one of these moths on my entomology page on Facebook, and it was immediately identified as the fall cankerworm, Alsophila pometaria (Harris), a moth in the family Geometridae. The caterpillars of geometrids are collectively called inchworms. Adult fall cankerworms present a striking example of sexual dimorphism. Males are fully-winged, while the females are wingless. Native to North America, fall cankerworms are found from Nova Scotia to South Carolina, west to western Alberta, Colorado, Kansas, and California.

Adult female fall cankerworm, Alsophila pometaria. ©2011, A.V. Evans

Adults are typically active in fall and early winter. Females lay batches of 50-200 carefully aligned and upright eggs on small twigs and branches. Before leaving, they cover their eggs with scales from their abdomen. Upon hatching in late spring, each caterpillar descends from its egg on a single silken strand and is dispersed by the wind.

The ravenous larvae consume leaves and young fruits of many kinds of deciduous tree and are especially fond of maple, oak, and elm. Young larvae “skeletonize” patches (cankers) on the undersides of leaves by eating only the leaf tissues between the small veins. Older larvae consume nearly all leaf tissues and leave only the major veins behind. After 4-5 weeks of feeding the caterpillars reach maturity and lower themselves on to the ground via silk strands to enter the soil to pupate.

Fall cankerworm. © 2012, A.V. Evans

Large numbers of fall cankerworm larvae can defoliate trees and seriously damage fruit trees. Most trees and shrubs can withstand the onslaught, but mortality is possible if the plants are already stressed from drought and other adverse conditions. Check with your local nursery or extension agent for information on effective controls for fall cankerworms.

References

Cranshaw, W. 2004. Garden insects of North America. The ultimate guide to backyard bugs. Princeton University Press, Princeton, NJ. 656 pp.

Johnson, W.T. and H.H. Lyon. 1994. Insects that feed on trees and shrubs. Second edition with corrections. Cornell University Press, Ithaca, NY. 560 pp.

Powell, J.A. and P.A. Opler. 2009. Moths of western North America. University of California Press, Berkeley, CA. 369 pp.

© 2011, A.V. Evans

SKY ISLANDS, DESERT SEA-Part II, Hornworm Highway

Posted in Arizona, Insects, Moths, Musings, Predators/parasites/parasitoids with tags , , , , on April 26, 2010 by Dr. Art Evans

By Arthur V. Evans

Charged by the onset of the summer monsoons in July or August, the arthropods of Arizona’s Sky Islands and desert seas are stirred into action.  The sudden and intense infusion of life-giving moisture triggers a flush of activity: eggs hatch, hungry larvae gobble up new leaves, adults are released from their earthen or wooden chambers, eager to mate and reproduce.  It is this marvelous intensity of arthropod activity that has drawn me to the mountains, desert scrub and grasslands of southeastern Arizona for nearly 40 years.

My earliest impressions of Arizona’s desert seas were formed by numerous overland trips from California in the 1970’s. Within minutes of crossing the Colorado River, the first saguaros would greet us, stationed like lone sentinels high on the rocky ridges of the Dome Rock Mountains. Although these giant columnar cacti have become symbolic of all arid regions of the southwest, they are strictly indigenous to the Sonoran Desert. These and other nearby desert ranges are capable only of supporting plants and animals adapted to fleeting amounts of rain. The summer monsoons, even at their height, seldom penetrate this far north and west.

Driving east from Gila Bend to the Maricopa Mountains, the stands of saguaros become taller and denser. Compared to the deeply pleated trunks of their western brethren, the almost bulging flesh of these plants is a clear sign of increased precipitation. The saguaros’ spongy inner tissues rapidly expand to absorb and store seasonal supplies of water as a hedge against the inevitable drought ahead.  Even the spiny ocotillo stand taller and greener here, surrounded by dense thickets of palo verde.  Here all living things enjoy the increased benefits of living under the blanket of the summer monsoons.

Another sure sign of increased rainfall is the sporadic population explosion of green and black-striped hornworms, caterpillars of the white-lined sphinx moth, Hyles lineata. Dozens to hundreds of these insects race across the hot, blistering highway in a scramble for tender desert greens. Some years there are so many of the caterpillars that the pavement becomes slick with their crushed bodies. At night marauding three-inch-long shield-backed katydids of the genus Capnobates rip chunks of sun-dried caterpillar from the road and grind them up with their powerful jaws, while scores of ants carve up the leftovers and carry them back to their underground brood.

© 2010, A.V. Evans

LUNA MOTHS ARE ON THE WING

Posted in Insects, Moths with tags , , , , , , on April 21, 2010 by Dr. Art Evans

By Arthur V. Evans

The luna moth, Actias luna (Linnaeus). Although the luna moth is native to North America, most of its relatives live in Asia.

Last night, while black lighting for beetles on a cool and still spring night in the Bull Run Mountains in northern Virginia, I was treated to an incredible display of luna moths, Actias luna (Linnaeus). Within an hour of turning on the lights, a baker’s dozen of these marvelously green and ornately tailed creatures had settled on the sheet and nearby tree trunks. Such a sight made me feel quite giddy and brought back a flood of memories of some of my earliest encounters with other spectacular insects as a young naturalist.

The first luna moth that I ever saw in Virginia flew through an unscreened upstairs window. It looked like a soft, green bat as it circled the light at the top of the stairs. It was all that I could do to keep it from being gobbled up by our cats!

They range throughout the hardwood forests of eastern North America. Luna moths were long known to naturalists by the time they were described by Carolus Linnaeus in 1758. The earliest known reference to luna moths in North America was in a note published James Petiver 1700, who had based his comments on a specimen collected in Maryland.

Like other moths and butterflies, the wings of luna moths are covered with scales that make up their colors and patterns.

Luna moths typically emerge from their cocoons in the morning. Powerful fliers, they are often attracted to porch lights and well-lit storefronts. There is only one generation produced in the northern parts of its range and two or three generations are produced in the south. Moths emerging in spring are bright green or blue-green with prominent reddish-purple margins on the outer forewings, while summer broods tend to be more yellow over all with yellowish outer wing margins.

Mating takes place after midnight. Pairs of luna moths sometimes remain coupled until the following evening. Eggs are laid singly or in small batches on upper and lower surfaces of leaves and hatch in about a week. The ravenous and solitary caterpillars feed on the leaves of a wide range of hardwoods, including birch, hickory, walnut, persimmon, and sweetgum. Different populations of luna caterpillars show regional preferences for host plants.

The feathery, or pectinate antennae of the male luna moth are covered with sensory pits that enable to them to detect just a few molecules of the pheromones released by receptive female moths.

Only when they are ready to pupate do the mature caterpillars wander away from the food plant. Cocoons are spun on the ground among the leaf litter at the base of the host tree. Each cocoon consists of a single layer of thin and papery silk that incorporates one or more leaves.

Sightings of the luna moth’s spring brood will still be possible over the next few weeks. Look for them at lights near wooded areas and you just might be treated to a glimpse of one of North America’s most spectacular animal species.

© 2010, A.V. Evans

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