An online resource based on the award-winning nature guide

Insects

Common Green Darners Appearing

6-20-17 common green darner 021The Common Green Darner (Anax junius) is one of our most common dragonflies. often seen near ponds. The family of dragonflies known as “darners” consists of species with large eyes and long abdomens that tend to rest infrequently and when they do rest, usually hang vertically. The Common Green Darner is the only North American darner in which the male and female usually fly in tandem when the female is laying her eggs on emergent vegetation.

Up to 50 of the world’s 5,200 dragonfly species migrate and the Common Green Darner is one of them. In the fall most (but not all) adult Common Green Darners migrate south to Florida, eastern Mexico and the West Indies. Huge clouds of migrating dragonflies have been seen along the East Coast, Gulf Coast and the Great lakes in autumn. Transmitters weighing 1/100th of an ounce that have been attached to migrating dragonflies confirm that they migrate much like birds. Just like avian migrators, they build up their fat reserves prior to migrating; they follow the same flyway as birds, along the Atlantic Coast; and like birds, dragonflies don’t fly every day but stop and rest every three days or so.

Some dragonflies mate and lay eggs along the way, while others do so when they reach their destination. The eggs hatch, larvae develop and the adults head north in the spring. Unlike birds, migration is only one-way for dragonflies. It is the offspring of the fall migrating generation that migrate north in the spring. Here in the Northeast, most arrive before any resident Common Green Darners have emerged. (photo:  female Common Green Darner)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.

 


Modest Sphinx Common & Scientific Name Correction

6-16-17 moest sphinx IMG_8668Poplar Hawk-moth and Big Poplar Sphinx are both common names used for more than one species of moth. Normally, the scientific name would clarify the identity of a species, but in yesterday’s post, the scientific name given was that of another moth with the same common name.

The confusion over the use of the same common names for different species of moths has led to the current use of the name Modest Sphinx for the moth depicted in yesterday’s post, with a scientific name of Pachysphinx modesta. It derived both common and scientific names from the fact that when it is seen up against a tree or other substrate with its forewings not fully extended, the bottom half of the moth is dark, as though “modestly covered” by a cloak or shawl. Thank you, Andree Sanborn, for your sharp eyes!

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Bumble Bee Queens Searching For Nest Sites

5-1-17 bumblebee 008This is the time of year when queen bumble bees have emerged from hibernation and are exploring for good nest sites, using both sight and smell. When searching for a suitable place in which to build a nest, a queen bumble bee flies in a distinctive zig-zag pattern low over the ground. If a certain cavity or hole interests her she will land on the ground and investigate by going into the crevice or hole.

Nest sites vary between bumble bee species. Most of the more common species prefer dry, dark cavities. Some nest underground, in places such as abandoned rodent holes, under sheds and in compost heaps. Of those that nest above ground, some make nests in thick grass, while others make nests in bird boxes and in trees.

Bumble bee nests are quite small, as they house only around 400 bumble bees (as opposed to a honey bee hive with a colony of 50,000 bees). At the end of the summer, if the nest has been successful in rearing new queens, they will leave the nest to mate and then go on to hibernate somewhere in the soil – ready to emerge the following spring to start their own colony. The original queen and the rest of the bees die as cold weather approaches.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Boxelder Bugs Active

4-6-17 boxelder bugs 095You may have noticed ½-inch-long black insects with red markings emerging from cracks and crevices inside or outside your home with the recent arrival of warmer weather. These are adult Boxelder Bugs that have been hibernating all winter and have become active with the warming days. They may disappear on days such as today when the weather turns cold again, but they’ll emerge for good in late April or May, just about the time buds on Boxelder trees are beginning to open.

During the spring and early summer they seek out and feed on low vegetation and seeds on the ground. Starting in mid‑July, they move to female seed-bearing Boxelder trees (or occasionally other maple or ash trees) where they lay eggs on trunks, branches, and leaves.  Red nymphs hatch in roughly two weeks, and proceed, like their parents, to feed on Boxelder foliage and seeds by using their piercing-sucking mouthparts. Even if their numbers are large, there is no noticeable feeding injury to these trees.   Come fall both adults and nymphs congregate in large numbers on the south side of trees, buildings and rocks exposed to the sun (only adults survive the winter) before settling in a protected hibernaculum. Boxelder Bugs are most abundant during hot, dry summers followed by warm springs. They do not bite people and are essentially harmless to property.  (Photo: adult Boxelder Bugs in spring; insert – adults and nymphs in fall) Thanks to Jeannie Killam for photo op.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.

 


Carpenter Bees Hibernating

email-carpenter bee holes IMG_1408If your home, shed or barn has weathered, unpainted wood and is riddled with ½”-diameter, perfectly round holes, there is a chance that carpenter bees are hibernating in them. Carpenter bees resemble bumblebees in both size and appearance (a carpenter bee has very few hairs on the top of its abdomen, which appears black and shiny, whereas bumble bee abdomens are often yellow and hairy), but they are not social insects. Instead of having a common nest in which they live and raise their young, carpenter bees drill  holes in wooden structures or trees inside of which they chew tunnels that contain six to eight brood chambers for their young. After creating the chambers, the female carpenter bee places a portion of “bee bread” (a mixture of pollen and regurgitated nectar) in each one. On top of each pile of food she lays an egg and then seals off the chamber. The larvae eat and grow, pupate and emerge as adult bees in late summer. At this point they feed on nectar, pollinating a wide variety of flowers before they return to their tunnels to over-winter.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.


Wingless Snow-walking Crane Flies

3-2-17-snow-walking-wingless-crane-fly-img_9477Thanks to a sharp-eyed Naturally Curious blog reader, a recently mis-identified active winter insect can be correctly identified. What I referred to as a “snow scorpionfly” last week was, in fact, a type of crane fly that, as an adult, has no wings. Like snow scorpionflies, these wingless snow-walking crane flies appear on top of the snow on warm winter days. These two kinds of insects are also very similar in shape and size, but, unlike snow scorpionflies, this group of crane flies have what are called halteres, knobbed filaments which act as balancing organs (see photo).

Scorpion snowflies, despite their name, are not true flies in the order Diptera.  Crane flies are.  Most species of true flies have one pair of wings, instead of the usual two that winged insects have, as well as halters, which take the place of hind wings and vibrate during flight. While wingless snow-walking crane flies lack a pair of wings, they do possess halteres, which are the key to distinguishing between a wingless snow-walking crane fly and a snow scorpionfly, which lacks them!  (Thanks to Jay Lehtinen for photo I.D.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.

 


Snow Scorpionflies Active

2-15-17-snow-scorpionfly-039On mild winter days you may wish to look closely at all the dark, little specks on the surface of the snow. Most of them will be bits of lichen, seeds or pieces of bark, but with luck you may find one or more of them moving. Active winter insects aren’t plentiful, but they do exist.

Scorpionflies are fairly common and can be recognized by their long beaks ending in visible mouthparts. (They get their name from one family of scorpionflies that possesses a scorpion-like tail.)  Snow Scorpionflies belong to a family of small, flightless insects, of which there are two species in the Northeast. They only measure about 2/10’s of an inch, so careful scrutiny is necessary to spot one. Their dark color and an anti-freeze substance in their blood allows them to remain active to 21°F., during which time they feed on mosses. When startled, Snow Scorpionflies often jump up in the air and land with their legs crumpled up (see insert) looking even more like an inedible speck of dirt. It’s fairly easy to tell their gender, as female Snow Scorpionflies (photo) lack wings, and males have bristly wings adapted for grasping females.

Naturally Curious is supported by donations.  If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.