An online resource based on the award-winning nature guide

Archive for June, 2011

A Tumble in the Night

Two nights ago good friends called to report that an animal had been screaming in their woods for about five hours, and asked if I knew what creature sounded like a human baby crying.   Because I am naturally curious, I had to see for myself what was making this commotion, so I headed over to the woods by their house.  It was immediately apparent from the cries that whatever was making them was in the forest canopy.  Looking up, you could see the leaves moving quite dramatically, and then suddenly, WHUMP!  A large porcupine fell out of the sky and onto the ground a mere 10 feet from where we stood.  It’s hard to say who was more surprised, the porcupine or the humans who narrowly escaped having a porcupine fall on their heads.  Upon close examination, it appeared that the porcupine must have tangled with one of its brethren, for several quills were sticking out of its face, with the pointed ends in the porcupine’s skin.  Apparently no bones were broken, as it eventually ambled off and climbed a nearby tree.  Perhaps a territorial dispute?  One can only hope that somehow the porcupine miraculously manages to extract these newly acquired quills.

 


Common Bladderwort

This slideshow requires JavaScript.

Common bladderwort is a carnivorous flowering plant – in amongst its finely-divided, submerged leaves, it possesses tiny sacs which were once thought to be flotation devices, but are actually highly specialized traps that capture, hold and digest food for the plant.   These sacs have a double-sealed, airtight door on one end.  When this door is closed, the sac, or bladder, expels water through its wall, creating a partial vacuum inside.  A leafy, feather-like structure hangs down adjacent to the door and the instant an organism bumps against this feathery trigger, it twists and breaks the seal of the door.  The vacuum inside causes water to rush in, pulling the victim along with it. As the bladder fills with water, the pressure is equalized inside and out and the door automatically closes, caging the plant’s prey.  This entire process takes 2/1000ths of a second.  As enzymes digest the prey, special cells in the bladder’s wall pump out the water and re-establish a partial vacuum inside, preparing the trap to spring again.


Weevils

The long-beaked insects known as weevils are actually a type of beetle. Weevils are chewing insects and their mouth parts or mandibles are located at the very tip of their snout.  They use this beak to drill through the shells of nuts, fruits, bark and other plant parts so that they can feed on the softer material within.  Female weevils also insert their eggs deep into plant tissues using these same drill holes.  Some weevils are considered pests of the plants (white pine, spruce, alfalfa and strawberries, among others) they eat and lay eggs in. The majority, however, are innocuous, and some even eat plants like dandelions, purple loosestrife and other plants generally considered to be weeds in the Northeast.

 


Blinded Sphinx Moth

This slideshow requires JavaScript.

The blinded sphinx moth, Paonias excaecatus, is a member of the Sphingidae family of hawk moths.  Most of this family’s larvae possess a horn at the tip of the abdomen.  The tomato and tobacco hornworm larvae are members of this family, as is the hummingbird clearwing moth.  The blinded sphinx moth has strongly scalloped margins on its forewings and a single blue eye spot on each of its two hind wings (which don’t show if the moth’s wings are folded).  Its common name derives from the fact that these “eyes” have no pupils.  In its larval stage, the green larva eats the leaves of  many deciduous trees, including willow, birch, poplar and cherry; the adult moth does not feed. After pupating underground, the adult moths emerge and mate.  Males (pictured) rest with their abdomen curved upwards.


Red-winged Blackbird Egg Hatching

Unlike most birds’ eggs, those of the red-winged blackbird hatch asynchronously – that is, they don’t all hatch at the same time.  Instead, their hatching is spread over several days.  During seasons when food is short, the young which hatch last often starve, as the earlier-hatched young, being larger and stronger, are the first to be fed, and thus deprive their siblings of food.  Having eggs hatch in succession is believed to be an adaptation that allows the size of the surviving brood to balance with the amount of available food. 

 


White-tailed Deer’s Sense of Smell

Being popular prey animals, white-tailed deer have evolved an extremely good sense of smell, sight and hearing.   Their elongated noses are filled with an intricate system of nasal passages that contain millions of olfactory receptors – up to 297 million (dogs have 220 million, humans just 5)!  As the tongue in this photograph infers, deer lick their nose to keep it moist, which helps odor particles stick to it, improving their sense of smell.  Not only do deer use their sense of smell to avoid predators (including hunters), but they use it to communicate with each other, as is evident from  the seven scent glands on their head, legs and hooves.


Wild Turkey Nest Predation

It’s fairly obvious that the eggs and young of ground nesting birds are extremely vulnerable. Eggs survive long enough to hatch in only about half of all wild turkey nests.  Predators, typically opportunistic feeders, look for the easiest and most accessible meals available.  Because of this, ground nesting birds, such as the wild turkey, often have a larger clutch of eggs than tree-nesting birds  Raccoons, opossums, skunks, crows and ravens will readily raid a turkey nest.  A nearby field was mowed yesterday, and much to the owner’s dismay, a turkey nest containing eggs was left exposed –  but the 11 eggs were intact.  The mother returned to the now-exposed nest, but upon visiting the nest this morning, a mere 12 hours later, I discovered the nest empty except for one egg which had been emptied of its contents.