Furcula with modified anal prolegs used to wave away potential predators
Many insects never make it to adulthood to complete their life cycles because in the grand scheme of things, they are low on the food chain. Between birds and amphibians, mammals and other insects, there is no lack of creatures that rely upon insects to muscle up themselves or to ensure their young survive long enough to obtain food for themselves.
But insects are not necessarily limpid little defenseless victims of a more sophisticated life form. They have strategies to overcome the odds of becoming dinner for something else. Some use camouflage, others are cryptic in manner and color, some have mastered the technique of veiling themselves with material and others simply hide. When you become familiar with specific species and their means of surviving, then it becomes easier to find them or to at least recognize them when you see them.
One of the ways insects can hide in plain sight is by coloration and feeding techniques. Spring caterpillars that feed on new leaves are often green in color. Late season caterpillars are differently colored and often have colorations or body forms that imitate the dead leaf spots and edges that occur at that time of year. Some feed along leaf edges and appear to be part of the leaf itself. Careful scrutiny will reveal the ruse. Two of the prominent caterpillars, the Wavy- lined Heterocampa and the Lace-capped caterpillar are just two examples of this behavior.
Wavy- lined Heterocampa feeding cryptically along the lower edge of a sweet birch leaf
Many assassin bugs that rely upon other insects as their food source will often lie in wait in places other insects are sure to visit. This includes flowers. Ambush bugs perch on flower heads, especially yellow and white composites, and wait for pollinators or nectar collecting insects to come to them. Ambush bugs are hard to spot on these flowers as they are the same color as the petals. They are motionless and are hard for even people to spot unless you look carefully for them. Often you will see butterflies that hang limply from flower heads. A close examination will reveal an ambush bug ( or a crab spider ! ) clasping the body and feeding off the insect’s fluids. Also, assassin bugs and predatory stink bugs often hide inside the folded seed heads of Queen Anne’s Lace and wait for other insects that use the structure as a hiding place to come inside. Opportunity may knock, but being in the right place at the right time is a better means of assuring survival.
Walking sticks are a good example of cryptic coloration and mimicry. Early nymphs are found on viburnum and filbert in New England. On these plants, both the insect’s shape and color allow it to blend so completely with that of the plant foliage that unless they move or cast a shadow, they are very hard to find. Later in the season, the older nymphs and adults change their food plants to oaks and cherries where they are able to blend in as their color changes to match the foliage of these trees. Camouflage loopers are small caterpillars that are found on composites. They take petals from the plant’s flowers and “ glue “ them on their body. They blend in so well that the only evidence of their presence will be that the flowers seems to be deformed.
Early nymph of a walking stick on native filbert. Note how legs blend in with the leaf veins.
Caterpillars, especially the slug moth caterpillars, can have defense mechanisms that utilize urticating hairs or venomous barbs to ward off potential predators. Handling some tussock moth caterpillars. the familiar woolly bears, Io moth cats and others may prove a painful experience for some people. One especially to be avoided is the saddleback caterpillar- small,l but able to inflict severe pain or burning sensation that lasts for several hours or even a few days. The body is covered with hollow spines that release an irritant when brushed or touched. Handled gently, many of these caterpillars will not harm the handler, but use caution around any caterpillar having barbs, hairs or spines. While many caterpillars that have spines and hairs have no toxins, unless you know for certain they are harmless, avoid contact with the skin to be safe.
Another means by which insects can protect themselves is by mimicry. Many flies have coloration and markings that are very similar to wasps and bees. These flies can also feed on the pollen of many of the plants that bees and wasps also visit. Birds will tend to avoid any insect that may have the potential to sting, so these bee mimics need not worry as they go about their everyday work acquiring pollen. The Virginia Flowerfly is one pollen- gathering bee mimic that is very common in Connecticut.
Stink bug nymphs hiding in grape leaf shelter
Many types of insects use leaf shelters as a means of hiding from predators by day. Besides caterpillars such as the Spicebush Swallowtail, stink bugs routinely use abandoned leaf shelters for themselves. I have especially found them by day huddling in small groups in leaf shelters on grape, which, along with raspberry, is one of the most common plants they feed on in the wild. Some spiders will use the same type of shelters, so be prepared for that surprise when you open any likely hiding places. Queen Anne’s lace is an especially good place to look for caterpillars, insects, assassin or other predatory bugs and spiders late in the year. Or look on goldenrod flowers, both for predators and caterpillars that feed on the flowers.
Slapping old molted skins on or using their own frass piled on their body is another way an insect either protect itself or camouflage itself to get clser to potential victims. Tortoise beetle larva use both methods to keep their presence unknown . All that can be seen is a small blob that looks like debris or frass. If disturbed, they may tip the mess up in the air over the body, somewhat like opening the trunk of a car. Then it is lowered again to conceal the soft body once again. Lacewing larva use their molted skins and other detritus to cover their body in a similar way. They can be found especially on white oak leaves this year. Look for a small, light tan, fuzzy pile moving across a leaf. This is probably a lacewing larva.
lacewing larva with molted skins covering it
Camouflage looper on daisy
Well, that is a brief look at some ways insects survive or attempt to survive in the world. There are many other ways and means insects employ subterfuge and the rest that could probably fill a book, but this is simply a leaf through…