All posts tagged Insects

By Lori Athey, Habitat Outreach Coordinator

It is high summer now and my early summer flowers are looking a bit tired while the late summer/fall show has yet to begin. Nonetheless, there is a lot of wildlife activity in my garden right now. The pollinators are all over the Echinacea/Purple Coneflower, Coreopsis, Butterflyweed and Beebalm, tired-looking though they may be. However, the big story right now in the habitat garden is happening in the leaves: that giant munching sound you hear is the caterpillars feeding.

Bees nectaring on Echinacea, purple coneflower.

Bees nectaring on Echinacea, purple coneflower.

If you have read University of Delaware Professor Douglas Tallamy’s book “Bringing Nature Home”, you already know that most (about 96%) of our songbird species need insects as part of their diet. Lepidoptera (butterfly and moth) caterpillars are a large diet component of insectivorous birds. Summer is prime Lepidoptera season both for caterpillars and mature adults. Some of the best plants for supporting caterpillars, and thereby birds, also provide nectar and pollen for other pollinators, fruits or nuts for the birds, insects and other critters, shelter, nesting material and good places to raise babies.

This big juicy caterpillar could be food for a hungry bird in your garden.

This big juicy caterpillar could be food for a hungry bird in your garden.

So here are a few plant superstars to try in your wildlife garden:

Do you have room for a tree? Oak (Quercus species) trees are champion providers for native caterpillars at 518 species, but they also provide pollen in the spring for the bees, acorns in the fall and winter for squirrels and other critters, as well as shelter and places to raise babies for all sorts of birds, insects and mammals. Especially lovely specimens for your garden are the Willow Oak (Q. phellos), Scarlet Oak (Q. coccinea) and Swamp White Oak (Q. bicolor).

This northern pin oak will provide great wildlife value to your landscape, as well as fall color.

This northern pin oak will provide great wildlife value to your landscape, as well as fall color.

Do you have a native Cherry Tree? Our native cherries and plums (Prunus species) support 429 native caterpillar species. They also provide pollen and nectar in the spring and fruit in the summer enjoyed by both insects and birds. In addition to the Wild Black Cherry (P. serotina), others to try include the American Plum (P. americana), and for your beach home, the Beach Plum (P. maritima).

This American plum is a fine plant to add to your backyard habitat for native pollinators, fruit-eating birds, as well as insects that will eat the leaves, providing more food for birds.

This American plum is a fine plant to add to your backyard habitat for native pollinators, fruit-eating birds, as well as insects that will eat the leaves, providing more food for birds.

Don’t have room for a large tree? Try one of our native Dogwood (Cornus species) trees or shrubs. Not only do these plants offer pollen/nectar, fruits and foliage for the critters, they also are very attractive as landscape plants with lovely flowers, pretty fruit and attractive fall foliage color. Try our common Flowering Dogwood (C. florida), or one of the large shrubs such as Redosier Dogwood (C. serecia) or Silky Dogwood (C. amomum).  Another superstar shrub is the Blueberry (Vaccinium species), which supports 286 species of caterpillars. Just like the others, it also provides nectar and pollen for the bees, and fruits relished by the birds but in a much smaller size, including dwarf selections. It too has pretty spring flowers, attractive fruit and lovely fall color. Plant several named varieties for the best fruit set.

Here, a Unicorn Caterpillar feeds on a blueberry bush.

Here, a Unicorn Caterpillar feeds on a blueberry bush.

We also have some superstar herbaceous flowering plants. Members of the Aster Family (Asteraceae) are standouts for supporting Lepidoptera caterpillars with their foliage, especially Goldenrods (Solidago), Asters (Eurybia, Symphyotrichum), perennial Sunflowers (Helianthus) and the butterfly favorite, Joe Pye Weed (Eutrochium). Some are just beginning to bloom now while others will bloom in early and late fall, providing an important source of late-season pollen for the pollinators, as well as seeds for the birds.

A Meadow Fritillary feeds on nectar from a blooming goldenrod, which will begin blooming in early August.

A Meadow Fritillary feeds on nectar from a blooming goldenrod, which will begin blooming in early August.

So plant some of these superstars in your garden and then put out the all-you-can-eat buffet sign for your birds and critters!

By Derek Stoner, Conservation Project Coordinator and Sheila Vincent, Public Program Coordinator

A Monarch caterpillar munches on a milkweed leaf at Ashland. Photo by Hank Davis.

Right now, the last generation of Monarch butterflies in our region are completing their life cycles.  The Monarchs we are seeing now are likely three to four generations removed from their ancestors that arrived here in early summer.

Last week, photographer and DNS board member Hank Davis captured an amazing series of images of Monarchs in all different stages, all in one tiny island in the middle of the Ashland parking lot!

A Monarch caterpillar hangs upside down in a typical "J" shape prior to forming its chrysalis.

In late summer, the adult Monarchs lay their eggs on milkweed plants as usual.  The tiny egg (smaller than a pin head) hatches after 5-7 days, and the caterpillar that emerges will feast on milkweed for 10-14 days.  When the caterpillar is mature enough (the final instar or stage), it will seek out a sturdy stem to hang from and curl up in  a “J.”

A freshly-formed Monarch chrysalis hangs from a goldenrod stem. Photo by Hank Davis.

The magnificent chrysalis is actually the last skin that the caterpillar will wear, and where it will spend the next 10-15 days transforming into a butterfly.

A Monarch chrysalis "ready to hatch" with the dark orange wings of the adult butterfly visible inside. Photo by Hank Davis.

The hardened skin of the chrysalis is an opaque pale green color until it is time for the adult Monarch to emerge.  Then the skin becomes becomes transparent and the butterfly breaks free.

After the adult Monarch emerges, all that is left is the paper-thin chrysalid case. Photo by Hank Davis.

The abandoned chrysalis looks and feels like tissue paper, and retains the wondrous gold and black speckling ringing the top.

This is how the next generation of Monarchs starts: a mated pair of Monarchs. Image by Derek Stoner.

The adult Monarch will hang for hours drying its wings, and finally set forth on its first flight to find nectar sources.  The twist, however, is that this generation is “programmed” to migrate south all the way to ancestral wintering grounds in the mountains of central Mexico.  How do they accomplish this amazing feat?  We don’t know the full answer!

If you’d like to learn more about Monarchs and explore their world, we invite you take part in the Monarch Migration Celebration this Saturday, September 18, from 10:00am to Noon, at the DuPont Environmental Education Center in Wilmington.  

On Saturday, September 25, from 2:00 to 4:00pm, families can take part in the Monarch Migration program at Burrows Run Preserve, where we will capture, tag, and release Monarchs on their way to Mexico.

For more information about these programs, please visit

By Derek Stoner, Conservation Project Coordinator

A Sleepy Orange butterfly at Middle Run Natural Area, 8/23/10. Photo by Hank Davis.

As late summer rolls along, there is a great deal of movement in wildlife populations.  We often think of the songbirds starting to move south and the Monarch butterflies beginning their long voyage to Mexico, but sometimes there are strange exceptions to the “head south as fall begins” rule. 

This week at Middle Run Natural Area, our birding group made a unique discovery of an uncommon butterfly from the south.  A Sleepy Orange, a member of the sulphur family related the our familiar Clouded Sulphur, appeared along the trail and its brilliant orange upperwing  captured our attention.  Hank Davis snapped some great photos to document this unusual find.  After consulting the field guides, we all had a “life” butterfly to add to our lists.   The Sleepy Orange is only rarely seen in our region in late summer, and thus becomes a prize find for us naturalist-types.

A Hickory Horned Devil Caterpillar at Middle Run, August 23, 2010. Photo by Hank Davis.

Another interesting insect that we came across is this Hickory Horned Devil caterpillar.  Nearly four inches long  and thick as a finger, this creature with the sinister-looking antenna still has a lot of growing to do.   These guys top out at six inches long and will turn a blue-green when they reach they final instar stage of caterpillar-hood.  Hickory Horned Devils are harmless, but they sure are a monstrous caterpillar! 

If you are interested in insects, join us for the second-annual Middle Run Bio-Blitz this Saturday, August 28, from 8:00am until early afternoon.  We will search for butterflies, dragonflies, bees, and other six-legged creatures.  Join in the fun at Middle Run!  We will meet in the main parking lot off of Possum Hollow Road.

By Derek Stoner, Conservation Project Coordinator

A female Regal Fritillary rests briefly on a yarrow plant at Fort Indiantown Gap. Image by Derek Stoner.

While soldiers train nearby to help in the fight for freedom, we wander along the carefully mowed fields amidst vast meadows ablaze with the colors of black-eyed susans, bull thistle, butterflyweed, yarrow, monarda, and other wildflowers.  Our eyes scan back and forth for the winged creatures that visit these flowers in search of nectar.   The flowers are seeking the same thing we are: butterflies.  In this unique location, one special butterfly is the attraction: the Regal Fritillary

A Great-spangled Fritillary glides above a male Regal Fritillary nectaring on Monarda. Image by Derek Stoner.

These gorgeous butterflies have a discerning taste when it comes to choosing habitat: weedy fields in poor soils that have plenty of violets, the host plant for the Regal Fritillary.  And not just any field will do, as these butterflies thrive in areas of disturbance.  A field that burns every few years spurs re-growth of violets and favorite nectar sources(thistles and milkweeds).   Where do you find such habitat?  At a military training ground, of course.

The sign says it all: You may want to watch your step while searching for butterflies. Image by Derek Stoner.

For the third year in a row, the Delaware Nature Society led a trip to Fort Indiantown Gap in Pennsylvania.  For several days each summer, this National Guard training base opens to the public for tours of its very special treasure.  Naturalists from the Fort led an assemblage of more than a hundred curious folks eager to see these winged wonders.  Amidst firing ranges, rusting battle tanks, ripped parachutes hanging in trees, and the multiple hand grenade training areas, we tiptoed along the trails in search of the rare Regals.  We saw plenty of Regals– likely 50 or more individuals out of an estimated population of more than 1,500 at the base.  That’s the largest single population of this insect in the entire world!

The Delaware state butterfly, the Tiger Swallowtail, is just one of the 81 species of butterflies documented at Fort Indiantown Gap. Image by Derek Stoner.

The intensely-managed and altered habitat at the Fort attracts a diversity of insect species, and our group  identified 25 butterfly species during our visit.  In the vibrant meadows we found other fritillary species like Great-spangled and Variegated, along with other beauties like Bronze Copper, Common Wood Nymph, Zebra Swallowtail, and Pearl Crescent.

If you are interested in butterflies join Delaware Nature Society staff member, Sheila Vincent on the program Butterflies for Grownups, Saturday August 7, 1:00 – 4:00 p.m.  Additionally, if you would like to help with a special citizen science project, we invite you to join us for the annual Butterfly Count sponsored by the North American Butterfly Association.  This year’s count will be held on Saturday, July 31,  beginning at 9:00 a.m.  Armed with nets, cameras, and notebooks, we will document all the butterflies we can find (and identify) at Ashland Nature Center and Burrows Run Preserve.  To register for this free event, contact Sheila Vincent at 302-239-2334, ext. 125.