The two-inch, skinny, black, shiny wasps with extremely long abdomens (five times the length of their bodies) that have been appearing on lawns lately are not the villains you may think. These female Pelecinid Wasps (males are much smaller and rarely seen) are actually beneficial, in that they greatly decrease the June Bug population. That long abdomen, or ovipositor, cannot sting you – it is strictly a mechanism for laying eggs. Its length is due to the fact that the wasp inserts its ovipositor deep into the ground in order to locate beetle larvae — specifically, June Bug beetle larvae. The wasp then lays one egg on each host beetle larva, and when the egg hatches, the wasp larva burrows into the host as it feeds on it, thereby killing the June Bug beetle larva. Eventually the wasp larva pupates and emerges above ground as an adult wasp the following summer – the phenomenon we are currently witnessing.
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Twenty minutes of observing air-borne visitors to a patch of roadside Chicory revealed nine different species of pollinators, including bees, flies and beetles. Most of the insects were bees, which makes sense, as honeybees, leafcutting bees and ground-nesting bees are the primary pollinators of this flower. Without exception, all of the pollinating insects were covered from head to toe with Chicory’s white pollen grains. As they circled the flowers’ stamens collecting pollen, the insects’ bodies were inadvertently dusted with some of it. Thanks to these diligent pollen-collectors and transporters, American Goldfinches and other seed-eating birds will be feeding on Chicory seeds come winter. (Electron microscopy by Igor Siwanowic and Scienceworks.)
The chipping of hungry Hairy Woodpecker nestlings can easily be detected by human ears, even though it comes from deep within a tree cavity. One is reminded of how beneficial this species is when observing the steady delivery of food by these woodpeckers to their young. More than 75% of an adult Hairy Woodpecker’s diet consists of injurious insects, while the amount of useful insects and cultivated fruits that they destroy is insignificant. Beetle larvae (mostly wood-boring) make up 30% of the insects that are consumed, with ants ranking second, at 17%. Caterpillars, such as those pictured, comprise about 10% of an adult Hairy Woodpecker’s diet, but given this parent’s beakful, one wonders if the percentage is greater for nestlings.
Tiger beetles (named for their ferocity) can be easily recognized by their quick, jerky movements, huge eyes and large, multiple mandibles. Look for these voracious hunters in sunny, open spots where they can easily spot prey and potential predators. The six-spotted tiger beetle is hard to miss, thanks to its iridescent green outer wings, or elytra. Contrary to that which its name implies, this species can have five, two or even no white spots. It is most likely to be found on exposed rocks, logs and tree trunks, whereas the twelve-spotted (may have 12 or fewer spots) tiger beetle tends to prefer moist sandy spots. They both capture and liquefy their prey by masticating it with their formidable mandibles, squeezing it and swallowing the juice. Both of these species of tiger beetles have a two year life cycle, overwintering as adults their first winter, emerging early in the spring, mating and laying eggs during the summer and then overwintering as larvae.
Black bears are omnivores as well as opportunists. They will eat almost anything that they can find, but the majority of their diet consists of grasses, roots, berries, nuts and insects (particularly the larvae). In the fall, prior to going into hibernation, black bears enter a stage called “hyperphagia,” which literally means “excessive eating.” They forage practically non-stop — up to 20 hours a day, building up fat reserves for hibernation, increasing their body weight by 35% in some cases. Their daily food intake goes from 8,000 to 15-20,000 calories (that’s roughly equivalent to 70 McDonald’s cheeseburgers). Signs of their foraging for grubs and beetles, such as the excavated base of the snag in the photograph, can be found with relative ease at this time of year, if you live where there are black bears. If you do share their territory with them, be forewarned that they have excellent memories, especially for food sources. Be sure not to leave food scraps or pet food outside (my compost bin was destroyed last year but I have no solution for that particular problem), and if you really don’t want any ursine visitors, it’s best to not start feeding birds until most black bears have entered hibernation – late December would be safe most years.
The Spined Soldier Bug is a predatory stink bug which preys on a variety of other insects (over 90 species), especially the larvae of butterflies, moths and beetles. It is one insect that farmers actually welcome, as it preys heavily on the larvae of the European corn borer, Mexican bean beetle, cabbage looper, Colorado potato beetle, flea beetles and many other crop pests. The adult Spined Soldier Bug has a prominent spine on each “shoulder.” It also has piercing-sucking mouthparts which it uses to impale prey and suck out their internal juices. The photograph shows a Spined Soldier Bug dining on the innards of a monarch caterpillar.
Flower Longhorn Beetles spend their larval life boring into decaying as well as live trees, depending on the species. As adults they leave their wooden tunnels to find food (nectar and pollen), new trees to tunnel in, and to mate. I recently found several pairs of Flower Longhorn Beetles mating on Queen Anne’s Lace, and all of the males had a transparent hose-like appendage coming from the tip of their abdomen which they inserted into the females as they bred. There is actually a name for this appendage – an aedeagus – and through it sperm capsules are delivered to the female. After breeding, the males retract their aedeagi, so they are not visible. Other insects possess aedeagi in different shapes and sizes, but those of longhorn beetles are considered to be among the most impressive.
A weevil is a type of beetle whose mouthparts are formed into a long snout, with one antenna on either side of it. The snout is used not only for feeding but also for making cavities in buds, fruits, seeds, stems, and roots of plants, where eggs are laid. When the weevil larvae emerge, they feed within the plant. There are 60,000 species of weevils, all of which are herbivorous and most of which are less than ¼ ” long. The species of weevil in the photograph was on many of the black-eyed Susans that were blooming in an unmowed field, and all of them appeared to be feasting on pollen. Many weevils are pests of plants such as cotton, alfalfa and wheat. You may have even found them inside your house devouring your cereal or flour.
Milkweed is in full bloom right now, presenting the perfect opportunity for young and old alike to discover the multitude of butterflies, beetles, bees and other insects that are attracted to these magnificent flowers. If you visit a milkweed patch, don’t leave before getting a good whiff of the flowers’ scent – one of the sweetest on earth. How many of the insects you find are carrying milkweed’s yellow pollen “saddlebags” on their feet? You might want to check out my children’s book, MILKWEED VISITORS, which I wrote after spending the better part of one summer photographing the various insects I found visiting a milkweed patch. ( http://basrelief.org/Pages/MV.html )
If you find a blossoming Trout Lily in the woods it is quite likely that you will also find one of its most common pollinators, the Red-necked False Blister Beetle (Asclera ruficollis), on it. Ardent pollen eaters, this group of beetles obtain their common name because many species cause blisters when pinched or squashed against skin. Adults mate on flower heads during pollen feeding. Both sexes feed on pollen, which acts as an attractant, but the female will not accept the male until her gut is packed full of pollen. She stores the pollen in a special intestinal sack in which an enzyme causes the pollen to partially germinate — this causes the indigestible covering of the pollen grain to rupture. She then digests the contents of the pollen grain, which she uses to manufacture eggs.
If you wake up and your lawn is full of small (1”-2” diameter) conical holes you can be sure of two things. One is that you have an infestation of grubs in your lawn. Secondly, a striped skunk has done you the favor of decreasing your grub population. Skunks are omnivorous, eating everything from snails and birds’ eggs to nuts and berries. In the summer, roughly half of their diet consists of insects. One of their favorites is beetle larvae (grubs), particularly the immature June bug larvae, which reside an inch or so beneath the surface of the soil. When skunks have been feeding under a pine tree, the circular motion with which they presumably dig the hole is obvious in the circular arrangement of the needles surrounding the hole.
Many ladybug beetles (ladybeetles) mate in the spring, but some species do so in late summer and fall. Each species of ladybeetle has its own pheromones for attracting a mate. Mating can last up to two hours, with the male climbing up and holding onto the female’s outer wings, while intermittently vibrating rapidly (making photographing them somewhat challenging). Their eggs hatch in 4 to 10 days, and within two weeks the larvae have matured into adults. Most of these aphid-eating predators will spend the winter hibernating, becoming active in the spring, when aphids are available once again.
If you want to get an idea of the number and variety of wasps, bees, beetles and bugs that reside in your area, go to the nearest goldenrod patch sit for a spell – this member of the Aster family is a magnet for insects. You’ll find many foliage- eating bugs and beetles, leaf-mining larvae, nectar and pollen feeders, and flower and seed-eaters. In addition, many predatory spiders (jumping and crab, especially) and insects (ambush bugs, ladybug beetles, flower bugs etc.) have discovered that goldenrod is a goldmine for them, as well. Researchers have found nearly 250 species of insects feeding on one species of goldenrod (Solidago canadensis). Pictured from left to right are a long-horned beetle (locust borer, Megacyllene robiniae - pollen eater), a fly (nectar feeder) and bee (nectar and pollen feeder).
Dogbane beetles , Chrysochus auratus, are suddenly here, and they are hard to miss. Look on the leaves of dogbane (also known as Indian hemp) for this iridescent blue-green beetle with a metallic copper and crimson shine to it. The young larvae reside underground, where they eat the roots of dogbane. When they mature into adult beetles, they climb up the plant to the leaves, which they then consume.