This is the time of year when it pays to watch where you walk – there are a number of ground nesting birds, some of which, including killdeer, may choose your lawn or even your garden to build their simple “scrape” nest. Typically killdeer nest on the shoulders of roads, gravel roof tops, fields and gravel parking lots. The nest is very primitive, and there’s actually very little to it — killdeer scrape a slight depression in the ground, to which they often add bits of material, including white objects such as shells and bones. Their pigmented eggs are extremely well camouflaged. The young precocial killdeer chicks are on their feet and feeding themselves as soon as their down feathers dry. (Photo by Sadie Richards)
Two species of weasels (smaller relatives of mink and otters) are found throughout New England – the long-tailed weasel (pictured) and the short-tailed weasel (also known as an ermine). Both are roughly the same size (somewhere between 9 and 16 inches), with long thin bodies and short legs. Visually telling these two species apart can be challenging unless you get a good look at both the tail and the body, and even then, it can be difficult. A short-tailed weasel’s tail is about 40% of the head and body length, whereas the long-tailed weasel’s tail is more than 45% of the head and body length. In the northeast, in November, both of these carnivores usually start shedding their brown summer coat for a white winter coat, and then molt and start growing in a brown coat again beginning in March. Further south, in Pennsylvania, less than half of the long-tailed weasels turn white, and none do south of the Pennsylvania/Maryland border. (Thanks to Tom Kennedy for photo op.)
Countershading is a common color pattern in animals in which the upper side of the animal is darker than the lower side. This color pattern provides camouflage for the animal when viewed from the side, above or below. The counter shading pattern balances the sunlight on the animal’s back and the shadow beneath the animal so as to blend the animal’s side profile with its surroundings. In addition, when viewed from below, a counter-shaded animal with a light belly blends into the light coming from the sky above. When viewed from above, the darker back of a counter-shaded animal blends into the darker ground colors below. Birds (which spend a considerable amount of time in the air) such as this dark-eyed junco, as well as marine animals often exhibit countershading.
White-tailed Deer fawns are close to two months old now, and will retain their spots until their gray winter coat grows in this fall. The dappling of the spots enhances a fawn’s ability to remain camouflaged up until it is large enough and strong enough to outrun most predators. However, it doesn’t hide them from biting insects. During the summer months, when White-tailed Deer, including fawns, have a relatively thin, cool coat of hair, they are very vulnerable to biting insects such as female horse flies and deer flies. These flies make tiny slices with their blade-like mouthparts in their host’s skin in order to have access to their blood. This fawn was being constantly bothered by such flies.
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 )
Many plants practice “delayed greening” of their leaves, including this Red Maple (Acer rubrum). An initial lack of chlorophyll prevents the leaves from photosynthesizing and making food, which means they have little nutritive value, and thus, appeal, to an herbivore. Most plants that delay greening have reddish leaves due to the presence of anthocyanin, a pigment which appears reddish. A majority of herbivorous insects and invertebrates cannot detect colors in the red range of the color spectrum. Young leaves suffer the greatest predation from invertebrate herbivores. Red leaves would be perceived by these leaf eaters as somewhat dark and possibly dead – not a choice food material. It is possible that the red coloration of new leaves allows the plant to make them unappealing to the herbivores that would otherwise eat them.
American Bitterns have returned to New England from their southern wintering grounds, and are announcing their presence with a unique song that Sibley describes as a “deep, gulping, pounding BLOONK-Adoonk” that they repeat over and over. These secret, well-camouflaged marsh birds are almost invisible as they slowly walk through marsh grasses. When they stand still and point their bill skyward, they are easily mistaken for the reeds they inhabit.
Can you find the brown creeper that’s on the trunk of this black cherry tree? This is cryptic coloration, a form of camouflage in which an animal blends into its environment, at its finest. A forager of insects and spiders tucked away behind and in the crevices of bark, the brown creeper starts its search at the base of a tree, climbing upward and often spiraling around the trunk until it nears the top. It then flies to the base of a nearby tree to begin the process again. As W.M.Tyler wrote in 1948 in Bent’s Life Histories of N.A. Birds, “The brown creeper, as he hitches along the bole of a tree, looks like a fragment of detached bark that is defying the law of gravitation by moving upward over the trunk, and as he flies off to another tree he resembles a little dry leaf blown about by the wind.”
With the warm temperatures this week, mourning cloak butterflies have been seen gliding through the leafless woods. Like eastern commas, question marks and red admirals, mourning cloaks overwinter as adults. They resemble dead leaves so much that from a distance the entire insect seems to disappear. Up close you can see the velvety texture of the wing scales, said to resemble the clothing mourners used to wear; hence, their common name. Mourning cloaks live up to ten months — an impressive life span for a butterfly. As they age, the yellow border of their wings fades to an off-white.
In an effort to look even more like a stick, this wingless common walkingstick (Diapheromera femorata), the only species of walkingstick in the northeast, has stretched its front pair of legs out straight in front of it, to either side of its two long antennae. In addition to being very well camouflaged, some species of walking sticks will rock their bodies side to side, resembling a twig swaying in the breeze. Worldwide, walking sticks range in length from an inch to over a foot and are often green or brown. Those in New England are usually about three inches length. Walking sticks are herbivorous, consuming the leaves of trees (often oaks) and shrubs, but we rarely see them, due to their camouflage as well as their nocturnal habits.