While crayfish are the most common crustacean in the United States, we don’t commonly see them on on the farm. This one was found by my son in the barely seeping fall headwaters of Carroll Creek. There is one fact that everyone should know about crayfish; they eat almost everything. Omnivores in the extreme, there’s nothing a crayfish won’t try: insects, tadpoles, algae, plants, dead animals, etc. They’ll feast on almost anything. In fact, one source states that 40% of their brain is devoted to their sense of smell – your brain only uses 1% – in order to help them find food.
Eastern tent caterpillars are generally not well liked. They can quickly defoliate small trees and gather in repulsive, squirming colonies. As if that weren’t bad enough, pregnant mares who accidently eat tent caterpillars are known to abort their fetuses. These facts make it even more surprising that these creatures are in fact one of the most fascinating caterpillars found on the farm. Not only are the amazingly sociable larvae capable of building the biggest nest of any tent caterpillar, they also vomit deadly cyanide when threatened.
Their nests are engineering marvels that are carefully constructed to keep the caterpillars warm. This is important because they can’t digest their food if they get too cold. Nests are typically started where two branches divide and expanded daily with new layers of silk. The widest side of a nest often faces the morning sun to capture as much warmth as possible. After several weeks, the nests develop into a multi-chambered, greenhouse-like structures that allow the caterpillars to control their body temperature. Their habit of gathering together in a large mass is also believed to have evolved in an effort to keep warm.
Their ability to produce cyanide is partially a result of their prefered diet of cherry tree leaves. Cherry leaves – especially those from the black cherry tree – are cyanogenic and provide the caterpillar with the raw materials necessary to make the poison. As a result, tent caterpillars are threatened by few predators other than the parasitic wasps and flies who lay their eggs on unsuspecting larvae.
While undeniably destructive, the damage done by these caterpillars often does not have a significant economic impact. Infested trees are typically ornamental and quickly sprout new leaves once the larvae leave to start the next phase of their life cycle.
The Variegated Fritillary is one of the many butterflies that enliven the farm’s fields and roadsides from late spring through fall. While it thrives from Argentina up through North America’s East Coast, its amazingly wide range also includes much of the United States and even extends into Canada. The Fritillary’s caterpillar hosts on leafy plants and vines including mayapple, moonseed, violets, and pansies. Adults typically feed on nectar from butterfly weed, milkweed, red clover, and, as seen in the photo, tickseed sunflower (Bidens aristosa).
A grove of ancient pecan trees draws a large number of gray squirrels to the farm. These industrious mammals are scatter hoarders. They can hide thousands of caches every year and feed on the stored nuts and seeds during times of scarcity. Primarily nesting either in collections of sticks and leaves called dreys or hollow tree trunks, female gray squirrels can give birth twice a year. They also do not hibernate. Instead they often share their nests on cold winter nights. Crepuscular by nature, gray squirrels are most active in the early morning and evenings.
Up until about a year ago I never expected to see a bald eagle on the farm. Due to excessive hunting by humans and the insecticide DDT, bald eagles were considered endangered or threatened for much of my childhood. Combined with the fact that they are sea eagles and principally eat fish, it was absurd to think I would ever see one in this part of Virginia. Yet here they are. Incredibly, it might even be a breeding pair that’s been visiting the farm over the past several days.
Their resurgence is the result of an amazing conservation effort. In the 1950s there were only 412 known nesting pairs. With the banning of DDT and severe restrictions on hunting, the birds are no longer listed as endangered or even threatened. Their increased numbers means that they are starting to re-occupy territory in parts of the United States where they have not been seen in living memory. Extremely cagey and hyper-alert, I have yet to get close enough for a decent photo of these amazing birds of prey. Even so, it is always inspiring to see this massive eagle – their average wing span can be 7-1/2 feet wide – take flight and soar over the family farm.
Found commonly over much of the east coast and as far west as Texas, the pickerel frog lives happily in Virginia’s Piedmont. While it looks similar to the leopard frog, the pickerel’s distinctive rectangular spots are an easy way to tell the two species apart. As you would expect of any frog, the pickerel is often found near streams and ponds. The lack of webbing between its toes also suggests that it spends more time on land than other frogs.
Amazingly, the pickerel frog is the only poisonous frog native to North America. Similar to eastern American toads, the toxin it secretes through its skin is only mildly irritating to humans if rubbed in the eyes or mucus membranes. However, its poison is more potent to smaller animals and even deadly to amphibians.
Doves. Pigeons. Flying rats. Birds from the Columba family are called by many names. Rock Doves are one of the most common birds in the world. While they are now found in almost every major city worldwide, their native habitat is Europe, North Africa, and South Asia. On the farm they typically roost under the hay hood of the barn and scavenge seeds in the surrounding fields.
Rock doves are known for being monogamous with both parents caring for clutches of one to two eggs. Amazingly, both parents also produce “crop milk” to nourish the squabs through their first week of life. Unique to doves, flamingos, and some penguins, crop milk is a dense mixture of fat and protein produced by the crop lining. The cheese-like secretion also contains antioxidants, bacteria, and immune-enhancing compounds.
Young squab is a also delicacy. While now they can be found in grocery stores, in 18th and early-19th Virginia wealthy landowners occasionally built elaborate dovecotes to attract breeding doves. These buildings – with their warm and cozy nesting boxes – allowed the gentry to easily harvest the young birds just days before they took their first flight.