Owlet Caterpillars of Eastern North America (Princeton University Press, 2011) is a lavishly illustrated field guide featuring more than 800 species of the most common, interesting, beautiful and important owlet moths and caterpillars found in eastern North America. Thousands of stunning images, information on larval diets, natural enemies and biology will help you identify the owlets near you. The slideshow in this article's Image Gallery features 50 of our favorite owlet moth and caterpillar images from the book. The following text has been taken from the book's introduction.
By virtue of their sheer diversity and abundance, owlet caterpillars and adults have become enmeshed in the ecological processes of forests, grasslands, and other terrestrial ecosystems. Owlet caterpillars are common on trees and most woody plants in the spring, when foliage is soft and rich with nutrients. Another peak of larval abundance occurs in late summer and fall, mostly on composites and grasses.
Owlet moths represent one of the most successful branches on the tree of life, whether measured in terms of species numbers, mass, or ecological importance. Caterpillars are a staple for insectivorous vertebrates. Birds are particularly reliant on caterpillars, and many insectivorous species time their nesting activities to periods of peak larval abundance—nestling survival would be appreciably lower in forests lacking owlet larvae. Goatsuckers move with storm fronts to feed on the abundance of moths that push northward on the leading edge of tropical storm cells— we estimate that greater than 90% of the moth biomass in these migratory swarms is made up of armyworms (Mythimna and Spodoptera), loopers (various Plusiinae), and other owlets.
Insectivorous mammals, including mice, shrews, raccoons, skunks, foxes, and many others, consume cutworms and other owlet caterpillars (and their pupae) found near the ground; some mice ascend shrubs and trees during their nocturnal forays for insect prey. Some insectivorous bats are dependent on moths and, by default, noctuoids. The colony of Mexican free-tailed bats that roosts under the Congress Avenue Bridge in Austin, Texas, is said to harvest more than 35,000 pounds of insects during the course of some nights. And the colony of 20 million Mexican free-tails that pours forth at twilight from Bracken Cave, Texas, purportedly consumes more than 100 tons of insects each night before returning to its roost. No doubt a healthy fraction, and perhaps the largest, is made up of noctuoids. Even mammals as large as bears feed on cutworm adults. Of particular importance are aggregations of the Army Cutworm (Euxoa auxiliaris), which aestivates by the millions in talus slopes in the Rockies. The communal gatherings are a critical food store for the grizzly bears of Yellowstone National Park and presumably for bear populations elsewhere. A single bear is estimated to eat 20,000 to 30,000 moths a day during portions of the summer—as much as one-third of the calorie required for an entire year may derive from the consumption of owlet moths (Mattson et al. 1991; French et al. 1994; White et al. 1998a, b).
The pollination services provided by noctuoids are underappreciated (Committee on the Status of Pollinators in North America 2007). Many cuculliines, hadenines, heliothines, plusiines, xylenines, and myriad others avidly seek nectar at flowers. Owlets are among the most common insects to visit flowers of apple, apricot, aster, basswood, buttonbush, campion, cherry, fireweed, goldenrod, jasmine, lobelia, milkweed, various orchids, phlox, pinks, red maple, wild plum, willow, white snakeroot and other eupatoriums, as well as other plants that offer nectar at night. Noctuidae may be the principal pollinators of Platanthera and other white-flowered orchids.
The indirect effect of plant-animal interactions on the quality and culture of our day-to-day lives are too commonly overlooked.
Owlet Moth and Caterpillar Photography
Visit the Image Gallery for our favorite photographs from Owlet Caterpillars of Eastern North America, or click on one of the titles below to navigate straight to the listed image.
- Sordid Snout Caterpillar, Hypena sordidula
- Sordid Snout Moth
- Citrus Fruitpiercer Caterpillar, Gonodonta nutrix
- Citrus Fruitpiercer Moth
- Three-staff Underwing Caterpillar, Catocala amestris
- Three-staff Underwing Moth
- Pink Underwing Caterpillar, Catocala concumbens
- Pink Underwing Moth
- White Underwing Caterpillar, Catocala relicta
- White Underwing Moth
- Gray Cypress Looper Caterpillar, Cutina albopunctella
- Gray Cypress Looper Moth
- Orange Panopoda Caterpillar, Panopoda repanda
- Orange Panopoda Moth
- Curve-lined Owlet Caterpillar, Phyprosopus callitrichoides
- Curve-lined Owlet Moth
- Light Marathyssa Caterpillar, Marathyssa Basalis
- Blurry-patched Nola Caterpillar, Nola cilicoides
- Blurry-patched Nola Moth
- Pink-patched Looper Caterpillar, Eosphoropteryx thyatyroides
- Square-eyed Dagger Caterpillar, Acronicta quadrata
- Yellow Spragueia Caterpillar, Spragueia apicalis
- Yellow Spragueia Moth
- The Laugher Caterpillar, Charadra deridens
- The Laugher Moth
- Hieroglyphic Caterpillar, Diphthera festiva
- Hieroglyphic Moth
- The Brother Caterpillar, Raphia frater
- The Brother Moth
- Eclipsed Oak Dagger Caterpillar, Acronicta increta
- Lesser Oak Dagger Caterpillar, Acronicta exilis
- Narrow-winged Dagger Caterpillar, Acronicta lanceolaria
- Narrow-winged Dagger Moth
- Miller Dagger Caterpillar, Acronicta vulpina
- Cottonwood Dagger Caterpillar, Acronicta lepusculina
- Harris's Three-spot Caterpillar, Harrisimemna trisignata
- Harris's Three-spot Moth
- Pine Sallow Caterpillar, Feralia major
- Pine Sallow Moth
- Sunflower Seedcopper Caterpillar, Stiria rugifrons
- Sunflower Seedcopper, Stiria rugifrons: in hidding
- Mustard Sallow Caterpillar, Pyreferra hesperidago
- Mustard Sallow Moth
- Hitched Arches Caterpillar, Melanchra adjuncta
- Hitched Arches Moth
- Convict Caterpillar, Xanthopastis regnatrix
- Convict Moth
- Western Bean Cutworm, Striacosta albicosta
- Western Bean Moth
- Citrus Fruitpiercer Caterpillar, Gonodonta nutrix, stretched out
This excerpt has been reprinted with permission from Owlet Caterpillars of Eastern North America by David L. Wagner, Dale F. Schweitzer, J. Bolling Sullivan & Richard C. Reardon, published by Princeton University Press, 2011.