Creature Feature: Common Buckeye

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Common Buckeye (Junonia coenia)

Common Buckeye

Junonia coenia

Family: Nymphalidae

Distinguishing Features/Description

Common buckeyes are medium sized, brightly colored and strikingly patterned butterflies.  Each of the buckeye’s four wings have two dark colored eye spots circled in a thin band of yellow.  The eye spots are positioned along the edges of the wings, and the two central ones on each side of the body are the largest.  The large eye spots on the forewings are surrounded by a thick white band, the shape and color of which are important identification features for separating this species from the other two North American buckeyes.  The leading edges of the forewings between the body and these white patches are brown, interrupted by two orange to red vertical lines parallel to the body.  The hindwings are mostly brown around the eye spots, with orange and yellow bands on the trailing edges.  The underside of the forewings is similar to the upperside, while the underside of the hindwings is much duller, with smaller less colorful eye spots and less patterning.  In the fall you might see common buckeyes “Rosa” form, with much brighter, pinkish hindwings.

The common buckeye is named after the resemblance of its eye spots to the eyes of male deer (bucks).  Interestingly, Native Americans named the buckeye trees with an indigenous word meaning buck eye, due to the nuts’ resemblance to bucks’ eyes, but there is no other apparent connection between the tree and the butterfly.

Common buckeye is the only buckeye in Virginia, so it is difficult to confuse with other butterflies in the state.  Two other buckeye species do live in the United States however, the mangrove buckeye in Florida and the tropical buckeye in Florida, Texas and the Southwest.  Both other buckeye species are duller, with smaller eye spots and not as bright colors compared to common.  Mangrove buckeye has orange instead of white bands on the forewings, which are bordered on the inside by black.  Tropical buckeye has very thin pinkish bands on the forewings and is much darker than common in general. 

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Common Buckeye (Junonia coenia)

Distribution and Habitat

Common buckeyes can be found throughout the southern United States year-round, but their range extends up to southern Canada in the summer months.  They are absent from much of the west, including Montana, Idaho and the surrounding states.  They are also present in Mexico and some of the Caribbean.

In Virginia common buckeyes can be found in a variety of open sunny habitats throughout the state.  They are present in many disturbed habitats, such as roadsides and pastures, as well as the many types of natural grasslands in the state, such as woodlands, savannas and prairies.  Common buckeyes can be found anywhere their generally prairie affiliated host plants can be found.

Ecology

Caterpillars are generalists on a wide variety of herbaceous plants, including plantain and wild-petunia.  Adults feed on nectar from a variety of plants, but the Asteraceae seems to be a favorite family.

On September 26th, 2018 CUH surveyed a piedmont prairie growing in a powerline right of way in Albemarle County.  We observed common buckeye caterpillars feeding on Agalinis purpurea (purple false foxglove), and adults in great numbers on Euthamia graminifolia (common flat-topped goldenrod).  The flat-topped goldenrod was growing in a large patch in the middle of a large and exceptionally biodiverse piedmont prairie remnant in a high-tension powerline right of way.  It was in the peak of its bloom, and the flat clouds of yellow flowers stood out from the surrounding broomsedge and other prairie grasses. Butterflies, moths and other insects including fiery skippers and swarms of common buckeyes fed from the flowers. Almost every flat-topped goldenrod flower had several buckeyes on it, the eye spots on their wings reflecting the sunlight in a dazzling array of iridescent colors.

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Common Buckeye (Junonia coenia) on Common Flat-topped Goldenrod (Euthamia graminifolia)

The scene above illustrates a couple of ecological relationships between the Piedmont prairie plant community and the common buckeye.  Many possible host plants for the buckeye grow in the prairie, including wild petunia and purple false foxglove, the latter of which we directly observed the buckeye caterpillar eating.  The prairie is also full of good nectar plants for migrating and resident adult butterflies, with the flat-topped goldenrod stealing the show in this scene.  The buckeyes, like other insects that feed on nectar, are inadvertently pollinating the plants they are feeding on.

Although we did not observe any predation of adults or caterpillars, they undoubtable serve as food sources for birds and predatory insects living in the powerline right-of-way.  The caterpillars are covered with thick dark spines, possibly serving as a physical defense from such predation, and of course the adult butterflies have the brightly colored eye-spots, which may serve as a distraction to predators.

Like the famous monarch, common buckeyes are at least partially migratory, with the first brood in the south of their range moving up into the northern US and southern Canada in the spring.  Different individuals fly back south in the fall, causing a peak in the numbers of common buckeyes in Virginia during their migration period.  Common buckeyes fly in Virginia roughly from May to October, with pupae surviving the winter.  They fly all year in the deep south but only briefly and sporadically in the northern part of their range during summer.

Creature Feature: Northern Bobwhite

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Northern Bobwhite (Colinus virginianus). Photo by Baxter Beamer.

Northern Bobwhite

Colinus virginianus

Family: Odontophoridae

Other common names: Bobwhite Quail, Virginia Quail

Distinguishing Features/Description

Northern bobwhites are a small, round bodied species of quail with short legs and tails. Their bodies are finely patterned with bold rufous, brown, black and white markings. Most bobwhite populations have a striped white and black head, with a white throat, dark eye stripe, white supercilium and dark crown. The only exception to this head coloration is the endangered subspecies masked bobwhite (C. v. ridgwayi) of southern Arizona, which has an entirely black head.

The coloration of male northern bobwhites varies significantly across their range, while females look similar. Eastern males have rich rufous colored chests and flanks and a light brown back. Males from the Southeastern U. S. are much darker overall, with a nearly black chest and very little rufous on the flanks. Western birds are paler, with some light rufous underneath and a pale gray back.

Northern bobwhites are the only quail throughout the eastern part of their range; however, they do overlap with scaled and Gambel’s quail in the West. Where they overlap with other quail species, bobwhites can be easily identified by their smaller size and brighter coloration, including their rufous chest and striped head.

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Scaled Quail (Callipepla squamata)

Distribution and Habitat

Northern bobwhites occur naturally in most of the eastern United States, roughly from Massachusetts to South Dakota and south through Colorado, New Mexico, and Texas to Florida. They also can be found on many of the Caribbean Islands and south through Mexico to Guatemala. Bobwhites have also been introduced to other parts of the world — including the Pacific Northwest and Europe — as a game bird.

In Virginia, northern bobwhites can be found statewide, although in many areas native populations have declined precipitously since the 1970s. Bobwhites are fairly rare in the Shenandoah Valley, becoming increasingly frequent as you travel east through the Piedmont and Coastal Plain. There are quite a few around Scottsville in eastern Albemarle, although some of these birds are likely hunting releases.

Northern bobwhites need early successional habitats — various natural grasslands and savannas — to do well, and the decline of these habitats in Virginia is probably a large cause of their decline. These kinds of prairies and open forests are maintained by disturbances, such as clear cutting or burning. Two plant communities that bobwhites rely on in Virginia are Piedmont prairie and loblolly pine savanna. Difficult Creek Natural Area and Piney Grove Preserve are two preserves in Virginia that exemplify these two plant communities respectively.

Piedmont prairies are a particularly diverse form of natural grassland, which makes them great habitat for bobwhites. The rich assemblage of flora that can be found in these disturbed habitats is often dominated by many species of grasses, legumes and asters. Since there are so many species of native plants, there are also many insects and seeds for the bobwhites to eat. The dense herb layer also provides cover from predators.

The diversity of flowering plants found in good bobwhite habitat also makes great habitat for pollinators. Many species of native butterflies, bees and wasps would also benefit from the restoration of natural grasslands.

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Piedmont Prairie at Difficult Creek Natural Area Preserve

Ecology and Life History

Bobwhites feed mostly on seeds and nuts in the fall and winter, but in the summer when they are raising chicks, they also eat many insects. Preferred seed sources include asters, legumes, grasses, pines and oaks.

Like other quail species, bobwhites live in groups — called coveys — of 3-20 birds. Coveys feed and sleep together, and they get along peacefully for most of the year, except during the breeding season when males fight for mates.

Nests are a shallow, grass lined scrape on the ground. Bobwhites often weave grasses over the nest into a canopy, forming a dome like shape. Typically, there is only one brood per season, but up to three have been recorded. Clutch size is large, usually more than 10 eggs. The young fledge after two weeks.

Notes

As mentioned above, northern bobwhites used to be a common bird in the eastern United States, but their populations have declined by 85% in the past 40 years, according to the North American Breeding Bird Survey. The IUCN Red List currently considers them “near threatened”. These declines have been attributed to widespread loss of the early successional habitat that bobwhites favor to development, forest succession, and more land intensive farming practices. Historically, the Piedmont of Virginia held extensive natural grasslands. What little remain today are widely scattered and fragmented. Bobwhites are only one of the many animals and plant species that rely on these incredibly biodiverse habitats.