Sleepy Orange Butterflies are Back

Sleepy Orange butterflies are back at Bowman’s Hill Wildflower Preserve!

Sleepy Orange butterflies on Purple Coneflower (Echinacea purpurea)

Sleepy Orange butterflies on Purple Coneflower (Echinacea purpurea)

Sleepy Orange (Eurema nicippe) butterflies are a tropical species, present year-round from Central America through the southern tier of the United States. They may breed as far north as the southern tip of New Jersey, west to eastern Colorado, then dipping south to near Las Vegas, Nevada, but they are less common in the northern part of their range, and they are not thought to be able to survive the winter much farther north than North Carolina. Sleepy Orange is a species that likes to push the envelope of its territory, with individuals migrating each year to repopulate the northern areas.

So it’s pretty exciting to have Sleepy Oranges at Bowman’s Hill Wildflower Preserve, because it’s considered a rare ‘stray’ in Pennsylvania where the Preserve is located. It’s rare across the Delaware River in much of New Jersey, too. In 2012, ours was the only count circle in Pennsylvania or New Jersey to report Sleepy Oranges in the July 4th North American Butterfly Association Butterfly Count.

Even better, I have seen Sleepy Oranges at Bowman’s Hill Wildflower Preserve in 2006, 2008, and every year from 2010 through 2013, usually from July through September. Yesterday I counted 10 individuals.

What brings them to the Preserve? Likely it’s the reliable presence of one of their favored caterpillar food plants, Wild Senna (Senna hebecarpa).

Wild Senna (Senna hebecarpa)

Wild Senna (Senna hebecarpa)

Wild Senna (Senna hebecarpa) flowers

Wild Senna (Senna hebecarpa) flowers

Only the presence of this food source has made it possible for Sleepy Oranges to breed at the Preserve. Sleepy Oranges also use other plants in this genus, and Partridge Pea (Chamaecrista fasciculata) and Wild Sensitive Plant (Chamaecrista nictitans) as food plants for their caterpillars. These plants are all pea family members, and contain alkaloids, chemicals that may have a bitter taste to some predators. Sennas also contain another chemical that has laxative properties. It is probable that Sleepy Oranges evolved to specialize on these plants because the chemicals they obtain from this diet offers some protection against predators.

Sleepy Oranges Mating

Sleepy Oranges Mating

There are also plenty of nectar sources at the Preserve for the adult Sleepy Oranges, who are pretty eclectic in their tastes.

Female Sleepy Orange  on Tall Tickseed (Coreopsis triptera), 2013

Female Sleepy Orange on Tall Tickseed (Coreopsis triptera), 2013

Sleepy Orange nectaring on Wild Bergamot (Monarda fistulosa), 2008

Sleepy Orange nectaring on Wild Bergamot (Monarda fistulosa), 2008

Sleepy Orange nectaring on Heal-all (Prunella vulgaris), 2011

Sleepy Orange nectaring on Heal-all (Prunella vulgaris), 2011

Sleepy Orange nectaring on Cardinal-flower (Lobelia cardinalis), 2012

Sleepy Orange nectaring on Cardinal-flower (Lobelia cardinalis), 2012

Males are also known to dine on minerals, although I usually see them drinking nectar.

Sleepy Orange on Field Thistle (Cirsium discolor), 2006

Sleepy Orange on Field Thistle (Cirsium discolor), 2006

Wondering about this butterfly’s name? It’s not based on behavior, because this sprightly butterfly is very active. The photo below illustrates the characteristics that explain the origin of the name ‘Sleepy Orange’. The curved pattern of dark dots near the center of the upper edge of the forewing are thought to resemble a closed eye, resulting in ‘sleepy’, and the bright orange color, especially coming from the top (dorsal) side of the wing explains the rest. Sleepy Oranges overwinter as adults in the south; their winter color form is a darker red-orange.

Sleepy Orange nectaring on New York Ironweed (Vernonia noveboracensis), 2010

Sleepy Orange nectaring on New York Ironweed (Vernonia noveboracensis), 2010

Given the rarity of this butterfly species in the surrounding area, I can’t help but wonder how Sleepy Oranges have been consistently finding Bowman’s Hill Wildflower Preserve for the past several years. It seems unlikely that this primarily tropical species would be able to survive the winter here, but with warmer winter temperatures, who knows? There are some reports of a southern migration of these butterflies in the fall. Could some of the Preserve’s butterflies have flown far enough south to successfully overwinter, and genetically pass on the knowledge of this location to their offspring? Does the generation that overwinters as adults live long enough to make a return northward migration the following year? Is this location near the Delaware River just a favored migration route for Sleepy Oranges and once they see the food available here they decide to stay? Random chance?

If you have an explanation or theory for their consistent appearance here, I would love to hear it!

Female Sleepy Orange on her caterpillar food plant, Wild Senna (Senna hebecarpa), 2013

Female Sleepy Orange on her caterpillar food plant, Wild Senna (Senna hebecarpa), 2013

For more on Sleepy Oranges at Bowman’s Hill Wildflower Preserve, click Sleepy Oranges Overwintering in Pennsylvania.

Resources:

Brock, Jim P.; Kauffman, Ken. Kaufman Field Guide to Butterflies of North America. 2003.

Capon, Brian. Botany for Gardeners. 2005

Cech, Rick; Tudor, Guy. Butterflies of the East Coast. 2005.

Glassberg, Jeffrey. A Swift Guide to Butterflies of North America. 2012.

Glassberg, Jeffrey. Butterflies through Binoculars A Field Guide to Butterflies in the Boston-New York-Washington Region. 1993.

http://www.butterfliesandmoths.org/species/Abaeis-nicippe

http://www.gardenswithwings.com/facts-info/a0810MonarchMigration.html

http://www.learner.org/jnorth/tm/monarch/OtherMigrants.html

Bowman’s Hill Wildflower Preserve – Visitors at the Pond

Plants are still filling in at the new pond at Bowman’s Hill Wildflower Preserve, but already the habitat is hospitable enough to tempt a variety of visitors.

New Pond at Bowman's Hill Wildflower Preserve

New Pond at Bowman’s Hill Wildflower Preserve

As you approach the pond’s edge, insect-sized American Toads (Bufo americanus) leap for shelter, escaping certain death from being squashed by a foot. They hide in the grasses, mulch, or under a plant leaf, hoping to remain unseen and unharmed. Compare the young American Toad with the clover leaves in this photo to get a sense of this tiny amphibian’s size.

American Toad

American Toad

Another not-fully-grown visitor along the pond’s edge is this pre-historic-looking Marbled Grasshopper (Spharagemon marmorata) nymph.

Marbled Grasshopper Nymph (Spharagemon marmorata)

Marbled Grasshopper Nymph (Spharagemon marmorata)

The flowers blooming near the pond’s edge are an attraction for many interesting animals.

Elderberry (Sambucus canadensis) flowers don’t produce a lot of nectar, but they attract insects that feed on their pollen, like the wasp-mimicking Toxomerus marginatus feeding here. This fly species doesn’t have a common name other than Flower Fly or Hover Fly, terms used to describe species of the Syrphid (Syrphidae) family because they make their living feeding on and pollinating flowers, and many are able to hover continuously for long periods. Members of this insect family evolved to look like bees or wasps, since this threatening disguise helps them to avoid predators. They feed on nectar or pollen, but their visits to the Elderberry flowers for food for themselves will also result in pollination, producing dark blue fruit later in the season.

Hover or Flower Fly (Toxomerus marginatus)

Hover or Flower Fly (Toxomerus marginatus)

Hover or Flower Fly (Toxomerus marginatus)

Hover or Flower Fly (Toxomerus marginatus)

An aquatic plant, Pickerelweed’s (Pontederia cordata) bright spikes of purple flowers are primarily pollinated by Bumble Bee species,

Pickerelweed with Bumble Bee

Pickerelweed with Bumble Bee

but they have many other visitors. Butterflies also enjoy their nectar, although their anatomy and feeding techniques are much less likely to result in pollination.

American Lady on Pickerelweed

American Lady on Pickerelweed

American Lady on Pickerelweed

American Lady on Pickerelweed

Least Skipper on Pickerelweed

Least Skipper on Pickerelweed

The airspace over the pond sees heavy air traffic from dragonflies and damselflies, constantly darting back and forth, feeding on other insects while both are in flight, and cruising for mates. What amazing flight navigation precision! Some females can be seen repeatedly touching the surface of the pond with the tip of their abdomen (the long slender body part that might look like a tail). This is how some dragonfly species lay their eggs.

The best chance to get a close look at these busy creatures is when they pause for a break on leaves, grasses or other plant matter or surfaces, while watching for potential mates or meals. Photography helps to enable a careful enough study to tell them apart.

Damselflies characteristically hold their wings folded together above their body, or only slightly apart. They are usually small with slender abdomens, a wide head and big eyes. Two species of Bluets were present on a recent visit, an Azure Bluet,

Azure Bluet

Azure Bluet

and a Stream Bluet.

Stream Bluet

Stream Bluet

Can you tell them apart? Look closely at the tips of their abdomens and count the number of segments that are blue, and check the width of the black and blue stripes on their thoraxes (the middle section of the insect, to which the wings are attached). Can you see any differences between the two damselflies in these characteristics or others?

Dragonflies generally hold their wings open, often perpendicular to their bodies, but at other angles, too. They are larger than damselflies and have stouter bodies, although different species vary quite a bit in size.

The dragonfly below is a Lancet Clubtail, resting on a clover leaf and some grasses. He’s missing a wing, probably the result of a recent encounter with an unsuccessful predator, possibly a bird, a frog, a spider, or another insect – even another dragonfly may have attempted to make him a meal.

Lancet Clubtail

Lancet Clubtail

Lancet Clubtail

Lancet Clubtail

Eastern Pondhawks, like the male pictured here, are among the dragonflies that are voracious predators of other dragonflies.

Eastern Pondhawk

Eastern Pondhawk

Male Blue Dashers spend a lot of time perching on vegetation, looking for a meal or a mating opportunity.

Blue Dasher

Blue Dasher

A male Widow Skimmer showed a preference for a Golden Alexanders flower stem as his perch, returning to it after each flight,

Widow Skimmer

Widow Skimmer

While Pickerelweed provided a favorite perch for this male Twelve-spotted Skimmer.

Twelve-spotted Skimmer on Pickerelweed

Twelve-spotted Skimmer on Pickerelweed

Twelve-spotted Skimmer on Pickerelweed

Twelve-spotted Skimmer on Pickerelweed

While I watched, Pickerelweed also played an important role in the courtship of a pair of Eastern Amberwings. I spotted a male first, perched a few inches above the water’s surface.

Male Eastern Amberwing, perching

Male Eastern Amberwing, perching

A few minutes later, I saw this pair mating at their rendezvous spot, the tip of a Pickerweed flower spike.

Eastern Amberwings Mating

Eastern Amberwings Mating

After a few seconds they parted. The male then led the female to a partially submerged cluster of Pickerelweed fruit, where she proceeded to lay eggs (oviposit), tapping the surface of the water while the male hovered nearby, preventing other males from undoing his efforts.

Female Eastern Amberwing laying  eggs (left) with male standing guard (right)

Female Eastern Amberwing laying eggs (left) with male standing guard (right)

Quite a show for such a new habitat!

The Pond at Bowman's Hill Wildflower Preserve, with photographer

The Pond at Bowman’s Hill Wildflower Preserve, with photographer

Resources

Barlow, Allen E.;  Golden, David M.;  Bangma, Jim.  Field Guide to Dragonflies and Damselflies of New Jersey.  2009.

Bugguide.net

Eastman, John.  The Book of Swamp and Bog.  1995.

Eaton, Eric R.; Kauffman, Ken.  Kaufman Field Guide to Insects of North America.  2007.

Nikula, Blair;  Loose, Jennifer L.;  Burne, Matthew R.  A Field Guide to the Dragonflies and Damselflies of Massachusetts.  2003.

Paulson, Dennis.  Dragonflies and Damselflies of the East.  2011.