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Archive for July, 2012

Spongilla Fly Cocoon

If you’ve never heard of a Spongilla Fly, you’re not alone. We don’t see its larval stage, as it lives under water, where it feeds exclusively on fresh water sponges. You can find these sponges living in the still waters of large rivers, lakes and wetlands. The beautiful silken net, as well as the small cocoon inside the net, are created by a Spongilla Fly larva after it crawls out of the water and chooses a spot on land on which to pupate (in this case on a seat cushion). The entire structure is less than ¼” in diameter.

Viceroy Butterfly

The Viceroy Butterfly closely resembles the Monarch Butterfly, but is smaller, and has a black line that runs across the veins of its back wings, which the Monarch lacks. While Viceroys don’t contain the poisonous cardiac glycosides that Monarchs do, they do contain salicylic acid due to fact that the larvae feed on willows. This acid not only causes the Viceroy to taste bad, but makes whatever eats it sick. So not only do these two butterflies look alike, but they discourage predators in the same way. This is not a coincidence. The fact that they are both toxic if eaten and are preyed upon by some of the same predators has led to their similar appearance. This phenomenon is referred to as Müllerian mimicry, and essentially it means if two insects resemble each other, they both benefit from each other’s defense mechanism — should a predator eat one insect with a certain coloration and find it inedible, it will learn to avoid catching any insects with similar coloration.

White-tailed Does Still Nursing

A doe giving birth for the first time usually has one fawn.  The following year, and until she is quite old, twins are the norm.  Triplets are fairly common, quadruplets are known, and there are at least two records of quintuplets.  Fawns nurse for eight to ten weeks before being weaned.  It’s apparent from this doe’s udder that her young are still nursing in late July.

Botfly Puparium

Congratulations on some very creative guesses!  Yesterday’s post  was a botfly puparium – a hard case made from an insect’s larval exoskeleton (skin) that covers and protects the pupa.  Most insects that go through complete metamorphosis (egg, larva, pupa, adult) don’t have this added protection for their pupal stage, but certain flies, including botflies, do.  Botflies are fairly large, hairy flies that resemble bumblebees and are internal parasites of many species of mammals, including humans. Depending on the species, the botfly deposits its eggs on or near the host animal, or on another insect, such as a mosquitoe or housefly, which carries them to their host. The eggs of some species of botflies are ingested or inhaled; those of other species hatch and the larvae bore into their host. After entering and crawling around inside of the host animal for a week or so, most species of botfly larvae settle in a spot just under the host’s skin and remain there for three to ten weeks, consuming the flesh of its host.  The lump, or “warble,” that forms just under the host’s skin where the botfly resides increases in size as the larva grows. A tiny hole chewed in the skin allows the larva to breathe, and eventually it exits through this hole.  The larva falls to the ground, where it pupates in the soil and later emerges as an adult botfly. (The two yellow bumps at one end of the puparium are spiracles, through which the pupa breathes.) The whole story of this particular puparium is that Jeannie Killam  found it in her old farmhouse’s kitchen cupboard, where it probably popped out of a visiting mouse.  (Illustration is of a human botfly.)

Mystery Photo

The subject of today’s Mystery Photo was submitted by Jeannie Killam of Barnard, Vermont.  It is approximately 1″ long, and 1/2″ in diameter.  Its identity will be revealed tomorrow — all guesses welcome!

Juvenile Green Heron

Green herons are typically solitary and secretive birds, but if you find one, you often have an extended period of time to observe it, as they often slowly stalk their prey, or pose statue-like, sometimes for minutes at a time, while waiting to strike at a fish, frog or invertebrate. Three characteristics tell you that the green heron in the photograph is a juvenile: the tufts of down that remain on its head, its streaked neck (adults have solid rufous necks) and its yellow legs (adults have orange legs).

Mating Flower Longhorn Beetles

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.

Big Brown Bat

New England is home to both the Little Brown Bat and the Big Brown Bat. While the Big Brown Bat’s wingspan is a bit larger than the Little Brown Bat’s, the physical differences between the two species are quite subtle. If you can get a close look at the face of either one, you stand a good chance of being able to identify it by the shape of its nose and the presence or absence of fur on its face. The nose of the Little Brown Bat is short (and looks as if it has been squished) and it is almost entirely covered with fur, while the Big Brown Bat’s nose is relatively long and there is very little fur between its ear lobes and the tip of its nose.

Young Muskrat Feeding on Cattails

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This young muskrat, probably about 2 months old, is still living with its family, but on its own as far as feeding itself. Typically, muskrats eat a variety of aquatic vegetation as well as an occasional clam, frog, crayfish or fish. This particular muskrat dines almost exclusively on cattails. Getting at the choicest part of these plants, the roots and inner stems, requires some serious digging in the mud, which is evident from the muskrat’s face in one of the photographs. Long nails on their front feet equip these rodents for this arduous task.

Monarch Butterfly Eggs Hatching

It appears that this may be a good year for monarchs in the Northeast, as with very little looking, you can find their eggs as well as young monarch caterpillars. Look on the underside of the top leaf or two on young milkweed plants – these leaves are tender and monarchs often lay their tiny, ribbed eggs there (usually one per plant) as they (leaves) are ideal food for young larvae. The first meal a monarch larva eats is its egg shell. It then moves on to nearby milkweed leaf hairs, and then the leaf itself. Often the first holes it chews are U-shaped, which are thought to help prevent sticky sap (which can glue a monarch caterpillar’s mandibles shut) from pouring into the section of leaf being eaten.

Immature Common Merganser Diet

Common Mergansers are primarily fish-eating ducks. Young mergansers require over half a pound of food per day during their first summer, and often supplement their fish diet with insects, mollusks, crustaceans, worms, frogs, small mammals, birds and plants. The pictured immature Common Merganser had just downed a crayfish when it spotted a frog which it succeeded in catching and eventually swallowing.

Close-up of Entire Organ Pipe Mud Dauber Nest

The images in a slideshow are smaller than if they were posted individually, so I thought I would include a single shot of the first image, showing all of the cells in the nest’s three tubes.

Inside Look at Organ Pipe Mud Dauber Wasp Cells

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Each “pipe” of the Organ Pipe Mud Dauber nest consists of several sealed cells (four, in this photograph), each stuffed with spiders (typically orb-spinning spider species) and one wasp egg. When the egg hatches, the white wasp larva consumes the paralyzed spiders, which are still fresh because they are still alive. Eventually, upon finishing the spiders, the larva will form a pupa case, and spend the winter inside it. In the spring the adult wasp will emerge from the case and chew its way out of the mud cell. If you look closely at the open, back side of these three “pipes” you can see that the oldest pipe is on the left, and contains cells with wasp larvae, whereas you can see mud dauber eggs lying on top of the spiders in two of the cells on the far right, in the most recently built pipe.

Skunk Cabbage Fruits

After the flowers of Skunk Cabbage, located on the knob (spadix) sitting inside a modified leaf (spathe), have been pollinated and fertilized, the fruits begin to mature. The spathe withers and dies, and the stalk that carries the fruit head elongates, growing along the surface of the ground. Initially the fruit head is green and dark purple, measures 2-3” in diameter, and has a convoluted exterior resembling that of a brain. Inside this compound fruit a circle of 10 to 14 seeds lines the periphery. By August the fruit heads will have fallen apart, and the seeds will lay on the ground where they will likely germinate or be eaten by squirrels, ruffed grouse or wood ducks. (Congratulations Liz, Josh and Deb on correctly identifying yesterday’s Mystery Photo!)

Mystery Photo

Today’s post was submitted by Thomas Hodgson of Martha’s Vineyard. Tomorrow’s post will identify it; meanwhile, guess away!

Organ Pipe Mud Dauber Wasps

There are basically two groups of wasps: 1) social wasps, such as hornets, yellowjackets and paper wasps and 2) solitary wasps, species that live solitary lives and typically hunt prey for their larvae (the adults consume nectar). Mud daubers are a type of solitary wasp.   Organ Pipe Mud Daubers builds cell out of mud in which they put prey (usually spiders) that they have stung and paralyzed, but not killed. They then lay an egg on top of the spiders, and seal the cell. After the egg hatches, the larval wasp consumes the still-fresh spiders, pupates, emerges as an adult wasp and chews its way out of the cell. In this picture a female Organ Pipe Mud Dauber wasp has collected a ball of mud and is applying it to the most recent cell she is making. The name “organ pipe” comes from the shape of the “pipes”, which consist of several cells, placed end-to-end, with the most recent cell at the bottom. (Notice the new, wet mud is darker in color.)

White-tailed Deer Fawn

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.


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.

Great Blue Heron Chicks Yawning

I had to laugh recently when I noticed a chain reaction going on in a Great Blue Heron nest I was watching. There were five chicks, and one of them yawned. At least I presume it was a yawn, though perhaps it could have be re-aligning its beak or perhaps cooling off. Exactly like humans, each of the remaining four birds followed suit and proceeded to stretch their beaks open wide in succession. It struck me as quite comical, especially when I discovered myself yawning as I observed the heron chicks doing the same.

Beaked Hazelnut

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The shrub Beaked Hazelnut (Corylus cornuta) is named for its fruit – a nut with a tubular husk that resembles a beak. The surface of the husk is covered with fine filaments that can irritate the skin. Rich in protein and fat, the hard-shelled nuts are a preferred food of Ruffed Grouse, Hairy Woodpeckers, Blue Jays, White-tailed Deer and squirrels. Beaked Hazelnut, a member of the Birch family, is quite versatile. Native Americans found many uses for its nuts – they ate them roasted and raw, pounded them for use in cakes, and used their oil as a cure for coughs, and colds, as well as an astringent. The wood of Beaked Hazelnut was carved into arrows, hooks and spoons, while the long, flexible shoots were twisted into rope. A European species of hazelnut is used for commercial production of hazelnuts (also called filberts) in the U.S.. The nut in this photograph has not matured and developed its hard shell, but I wanted to beat the squirrels to it!

Red Fox Kits Growing Up

Remember those sand-colored, fuzzy fox pups of two months ago? They have grown in their third coat since birth (finally they are really “red” foxes!), their noses have lengthened and their size makes them hard to distinguish them from their parents. Even though they appear adult-like, the kits’ continued playfulness gives away their age.

American Lady & Common Milkweed Pollinia

If you look really, really closely you may be able to see Common Milkweed pollinia on the American Lady’s feet.

Common Milkweed Pollination

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The structure of the Common Milkweed (Asclepias syriaca ) flower is such that its pollen, produced in two saddlebag-like sacs with a black appendage joining them, snaps onto an insect’s leg when the two come in contact with each other. To assure that the chances of this are high, the pollen sacs (pollinia) hang inside a slit that is located between each of the five cups, or hoods, that contain nectar. An insect lands on the slippery flower, attracted by both the scent and availability of nectar, and inadvertently one or more of its six legs slips down between the hoods into a slit, where the pollinia automatically attach to the leg. The insect withdraws the leg upon leaving to find more milkweed nectar, and the attached pollinia eventually falls off onto another milkweed flower, pollinating it. Unfortunately, about 5% of milkweed flowers visited trap insects because they cannot extract their legs from the slit. It is not uncommon to see an insect dangling from a Common Milkweed flower – during a 30 minute visit to a milkweed patch recently I released 2 flies, 3 skippers (butterflies) and one honeybee that were caught, but hadn’t yet perished.

Leafcutter Bee Cell Leaf Sections

At the risk of boring readers, I wanted to include one final Leafcutter Bee post, showing the two basic shapes that these bees chew out of leaves in order to make their incubator/nursery cells.  There are oblong pieces, roughly an inch long, as well as perfectly round, ¼-inch diameter pieces.  Each cell consists of several layers of oblong pieces rolled lengthwise which are sealed at one end with a round piece of leaf.  The round end pieces appear to be glued into place (perhaps with the pollen/nectar mixture?) at one end of the cell, leaving the opposite end open.  The cells are arranged end-to-end, with the open end of the cell placed against the sealed end of the next cell.  Together they form a nest that is somewhat cigar-shaped and is typically located a few inches down in the soil, or in a cavity.