Friday, September 26, 2008

Nature Trivia #5


* The "caduceus" the classical medical symbol of two serpents wrapped around a staff—comes from an ancient Greek legend in which snakes revealed the practice of medicine to human beings.

* A "chickadee" was a Michigan logger whose job it was to spread horse manure on steep icy hills. The purpose was to slow down, by friction, the sleigh's loaded with 16ft. virgin timber logs coming down the ice road slopes.
* The anaconda, one of the world’s largest snakes, gives birth to its young instead of laying eggs.

* The animal responsible for the most human deaths world-wide is the mosquito.

* The average adult male ostrich, the world’s largest living bird, weighs up to 345 pounds.

* The Canary Islands were not named for a bird called a canary. They were named after a breed of large dogs. The Latin name was Canariae insulae — "Island of Dogs."

* The catgut formerly used as strings in tennis rackets and musical instruments does not come from cats. Catgut actually comes from sheep, hogs, and horses.

* The chameleon has several cell layers beneath its transparent skin. These layers are the source of the chameleon’s color change. Some of the layers contain pigments, while others just reflect light to create new colors. Several factors contribute to the color change. A popular misconception is that chameleons change color to match their environment. This isn’t true. Light, temperature, and emotional state commonly bring about a chameleon’s change in color. The chameleon will most often change between green, brown and gray which, coincidently, often matches the background colors of their habitat.

* The cheetah is the only cat in the world that can’t retract its claws.

* The giant squid is the largest creature without a backbone. It weighs up to 2.5 tons and grows up to 55 feet long. Each eye is a foot or more in diameter.

* The honeybee kills more people world-wide than all the poisonous snakes combined.

* The hummingbird, the loon, the swift, the kingfisher, and the grebe are all birds that cannot walk.

* The mouse is the most common mammal in the US.

* The Pacific Giant Octopus, the largest octopus in the world, grows from the size of pea to a 150 pound behemoth potentially 30 feet across in only two years, its entire life-span.

* The turkey was named for what was wrongly thought to be its country of origin.

* The underside of a horse’s hoof is called a frog. The frog peels off several times a year with new growth.

* The venom of a female black widow spider is more potent than that of a rattlesnake.

* There are around 2,600 different species of frogs. They live on every continent except Antarctica.

* There are more insects in one square mile of rural land than there are human beings on the entire earth. There are more than 900,000 known species of insects in the world.

* Though human noses have an impressive 5 million olfactory cells with which to smell, sheepdogs have 220 million, enabling them to smell 44 times better than man.

* Tigers have striped skin, not just striped fur.

Sunday, September 21, 2008

Nature Trivia #4


• The flamingo sits down to bathe and to nest. What makes this a curiosity is that the flamingo doesn’t sit down much. It is on its feet, or foot, (whichever), more than any other bird.

• Bird claws, like human fingernails, grow con- tinuously. In the wild they do not have a chance to grow too long because the birds are always work- ing their fingers to the bone, trying to make ends meet and building a nest egg.

• Old filmmakers put the call of the kookaburra on the soundtracks of almost every jungle movie ever shot. But the kookaburra lives only in Austra- lia. [I bet Tarzan knew that!]

• Homing pigeons equipped with tiny alumi- num cameras were used by both sides during WWII to photograph areas too heavily fortified to be flown over by planes. The cameras were activated by air rushing through a rubber ball.

• The heaviest chicken you ever wanted to meet belonged to Grant Sullens of West Point, Calif. He had a monstrous rooster named "Weirdo" who weighed in around 22 lbs. Weirdo was so mean that he crippled a dog which came too close and he killed two cats. Now that is what I call "Poultry in Motion"!

• The Canada goose uses 12,000 muscles to move its feathers.

• The pelican, when fishing, with each catch scoops up more than a gallon of water.

• A robin worm-hunting on the lawn and cock- ing his head as though he were listening is merely trying to bring his eye into position so that he can see where the worm is. Birds’ eyes (with few exceptions) are set in the sides of their heads, and they see out to the sides rather than straight ahead; they do not have bifocal vision as humans do.

Saturday, September 20, 2008

Totem Art


Totem figures represent much in the way of legend and family relationships. They also repre- sent a relationship with the Earth and its history.

Bird representation on totems can be recog- nized by their beaks, irrespective of the type of face to which they are attached. Various birds, in turn, can be identified by the shape of the beak. A straight beak for the raven, curved for the eagle, and curved until the tip rested on the mouth or chin for the hawk.

The art of totem evolved into neither realistic nor symbolic representation, but a mingling of the two.

World politics have evolved the same way. It is very hard to distinguish the realistic from the symbolic.

There was a point when U.S. politics entered into native culture and at the same time totem sculpture. The tribes of the northwest began to put Abe Lincoln’s top hat on the peak of many totems. He was the Great White Father.

Totem art was not a technical representation of that which it represented. Specific body parts would be used to represent an animal. The beaver was indicated by large incisor teeth, a killer whale by the dorsal fins and blow hole, the grizzly bear by a large mouth full of teeth, and the Great White Father by not only the top hat but the large mouth and protruding forked tongue.
The clan totem is a symbol for a tribe, clan, family, or person. They are carved in the associa- tion of the clan with a particular plant, animal, or other natural object. The clan considers these to- tems holy and pray to them. The totem oftentimes represents an ancestor. One bonus for the species represented on the totem was that often it was forbidden for the clan to kill or eat the species belonging to the totem. You will seldom see pizza and beer on a totem. It is believed these are items that most tribes just did not want to give up.

Totemism, as a form of religion, is widespread among primitive tribes. Many North American tribes, particularly those of the Pacific Northwest, carved birds as their clan emblems on totem poles. The tribe held a potlatch, or feast, when the totem poles were put up.

Sunday, September 14, 2008

Nature Trivia #3


* Worms don’t have eyes, but they can feel light through their skin.
* The smallest living things are called microbes. One cup of soil may contain more living creatures than there are people on the whole planet.
* There are more than 700,000 different types of insects.
* Spiders are not insects. Insects have six legs, and spiders have eight. Most insects have wings. Spiders do not.
* Toads live up to 40 years. Toads chew their food, such as worms, with their eyeball muscles. That’s why they close their eyes when eating.
* Moths and butterflies have a fine powder on their wings that helps them fly. Never pick up but- terflies by their wings.
* A common shrew eats three times its own weight in insects every day.
* A shooting star is not a star at all. It is a meteor, which is actually a bit of dust traveling through space at a very high rate of speed. When it hits Earth’s atmosphere, it gets so hot it glows! That trail of glowing dust is what we call a shooting star.
* The word "photography" is based on Greek words meaning "write with light."
* Bees have no hearing. Mosquitoes are attracted to blue more than any other color.
* You could fit 20 newborn opossums into one tablespoon.
* An octopus has three hearts.
* An elephant has 40,000 muscles in its trunk.
* Fish and snakes can not blink, which makes it extremely difficult to flirt.
* The tarantula can live without food for up to two years. But then don’t be standing in front of the refrigerator.
* Woodpeckers have unique physiology, including a skull that contains cushioning tissues to protect the bird brain when it is chiseling into trees and a kick-stand tail that doubles as a shock absorber.
* Many birds shut their wings periodically while flying to conserve energy and open them again to prevent crash landings.
* Ducks and geese beat their wings constantly during flight.
• With neither a brilliant plumage nor a melodic song to set it apart from other birds, the crow might seem to have been dealt a low blow. But animal behaviorists have long believed that the crow has at least one thing in its favor. It is among the most intelligent birds in the world, with some species so advanced that they make and store their own tools to extract food from hard-to-reach sources, such as holes in trees.

• Antler flies spend their lives within the same few square meters, feeding and mating during the day on a moose or a deer antler, sleeping at night in nearby vegetation.

• The barred owl is so called because of the marks that look like bars across its breast.

• The northern shrike is not a raptor, but it always wanted to be.

• Female Water Fleas carry their eggs in a brood pouch, much like a backpack. This pouch is located between their carapace and their body. Vernal pool Water Fleas sometimes carry up to 20 eggs. The brood pouch can become so heavy that the Water Flea tips over. She has to swim upside down until the eggs hatch and the young Water Fleas swim away.

• In winter Red-winged Blackbirds join noisy foraging (hunting and feeding) flocks of 500 to over 5000 birds of several species: Brewer’s Blackbirds, Tricolor Blackbirds, Starlings and Brown-headed Cowbirds.

Saturday, September 13, 2008

Nature Trivia #2


• The tree frog’s remarkable ability to climb or rest on vertical surfaces is the result of a mucous layer produced by toe pad cells. This mucous creates a sticky bond with the vertical surface that’s strong enough to support the frog’s weight.

• A great time to enjoy activity at the bird feeder is after a snow storm or even sleet. Both these conditions cover natural food sources and makes your feeder handouts very attractive.

• Hemiptera (Sucking bugs) Also called "Squash Bug" or "Stink Bug", it is a very common insect in North America. This variety is common in the Midwest and can be found up to 1" long. When squashed a very strong odor emits from the thorax (body). This is to deter birds and mammals from eating them. Some subspecies on the East Coast can cause blisters to the skin; however, in the Midwest, this variety does nothing other than smell bad.
I have a bunch of them out here in the deep woods of Michigan. They invite themselves in when it gets cold. They can fly faster than a Denny McLain fast ball. They entertain the cats and are very intricate in design and pattern. I feel bad every time I flush one.


• Crow, house sparrow and starling problems can be eliminated by seed and feeder selection.
Cats are another story altogether. Feral cats and your neighbor’s tabby are a serious threat to nestlings, fledglings and roosting birds. Too often, the presence of just one cat on the prowl near your feeder can take the enjoyment out of your backyard bird watching experience.
If there are no cats in your neighborhood and you find a pile of feathers near your feeder, look for a hungry hawk perching on a tree nearby.
Don’t get upset. Consider yourself fortunate to see one, right in your backyard. Cooper’s and sharp-shinned hawks eat birds and play an important role in the natural community.


• When birds desert your feeder, it may be simply that you haven’t offered them coconut. It’s the Jimmy Buffett buffet, or a lot of natural food is available nearby. Or something may be wrong, such as your seeds are spoiled or your feeder contaminated. Throw the seeds away and wash the feeder. Take a look at where your feeder is placed. Be sure it’s not vulnerable to predators.

• Birds don’t have sweat glands in their feet, so they won’t freeze onto metal feeders. There’s no need to cover any metal feeders parts with plastic or wood to protect birds feet, tongues or eyes.
• There’s no evidence that birds can choke on peanut butter. However, birds have no salivary glands. You can make it easier on them by mixing peanut butter with lard, cornmeal, and/or grit. Your birds will appreciate a water source too—a bird bath or trough.

• In the winter, you may see flocks of birds along roadsides after the snowplows have passed. They’re after the grit. Birds have no teeth to grind their food. The dirt, sand, pebbles, and grit they eat sits in their crop and helps grind up their food. Adding grit to your feeder is helpful year-round, but particularly in the winter and spring. Crushed eggshells do the same thing, and in the spring have an added benefit. They provide extra calcium during nesting season.

• It’s natural for moths to lay their eggs in sunflower seeds. The eggs lay dormant as long as the seeds are stored in a cool dry place. In the summer, seeds get hot and the eggs hatch. The best way to avoid this problem is to buy seeds in smaller quantities, or store your seeds in a cool, dry place.

Basic Birdfeeding Knowledge


• It’s best to put your feeder in a quiet, yet convenient area that has year-round easy access. When the weather is bad, you may be reluctant to refill the feeder. Remember that this is probably when your squirrels need you the most!
It’s a good idea to place your feeder near natural cover such as shrubs. By providing nearby shelter, you offer a place where the birds can hide from predators and out of the weather while waiting for their turn to feed. Evergreens are particularly good because they provide excellent cover year-round.
You also need to consider the "mess" factor. Expect feathers, seed shells, and droppings and select a location where clean-up will not be an issue.
Be sure to clean your seed feeders at least once every two weeks to prevent spoilage and disease. Often seed can become moldy, and diseases such as salmonella can grow in moldy, wet seed. If you have a hummingbird feeder, be sure to clean it at least once per week.


• Woodpeckers are notorious for their noisy springtime mating ritual. However, during the summer months, they are welcomed exterminators for insects and other tiny pests. Their diet consists mainly of ants, moths, borers, scale insects, grasshoppers, grubs, beetles, millipedes, crickets, wasps, aphids, caterpillars, spiders, and other flying insects.
To help you combat these pesky garden enemies, you may consider attracting woodpeckers to your yard. Planting various fruit trees and bushes can be as effective as placing the appropriate feeders in your yard.
Although their staple food group is insects, woodpeckers also enjoy feasting on fruits and nuts. Planting berry-producing bushes or trees such as dogwood, apple, serviceberry, black cherry, flowering crabapple, common spicebush, golden currant, walnut, black gum, holly, red cedar, bayberry, or sugarbush will draw them to your yard. You can also attract woodpeckers by providing cracked corn, grapes, raisins, peanut butter, or apples on a platform feeder.
Because the majority of a woodpecker’s diet is animal protein and fats, suet is the perfect supplement to their diet. Suet, the fat that collects around beef kidneys, is available at grocery stores or at your local garden center. There are a variety of ways to offer suet. Suet can be smeared in the bark of a tree or mounted in hardware cages that are wired to posts or tree trunks. When feeding suet in the warmer months, monitor the feeder regularly to be sure the suet has not become rancid.
Woodpeckers also enjoy peanuts. Use unsalted cocktail peanuts in the jar or buy them in bulk at your local feed store. Peanut feeders are the safest way of feeding peanuts. These feeders are typically made of wire mesh and force the birds to peck at the nuts and get only small pieces. Your peanut feeder will also be visited by titmice, nuthatches, and some wrens!


• Once you get your bird feeding station up and running, you may run into problems with uninvited guests. These visitors fall into two categories — those interested in the seeds (squirrels and chipmunks, rats and mice, starlings and house sparrows), and those interested in a bird for dinner (cats and hawks).
Squirrels are for entertainment. Never let them see you sweat. You can learn to love them while you love to hate them. Those who love squirrels tolerate their visits, and may even encourage them with special squirrel toys and feeders.
Usually when a squirrel is at the feeder, you’re not likely to see birds. But some birds have learned that if they want any seed they have to be a little pushy. Squirrels will scare off the birds while they eat the seed, and sooner or later they’ll eat the feeder too.
Chipmunks, rats and mice can also become a problem where there’s seed spillage under the feeder. Don’t use mixed bird seed, and if you don’t want squirrels at your potluck add a feeder tray.

Who's a Turkey?


When you call a person a "turkey" it doesn’t mean they are stupid—it means they are a bit odd--Well, most of the time anyway!


The turkey is one of the most famous birds in North America. Benjamin Franklin wanted to make it the national bird.



The turkey’s popularity comes from our love of eating the bird for special occasions like Thanksgiving and Christmas.



The wild turkey we usually see in photos or pictures is not the same as the domestic turkey that we serve at Thanksgiving.



Domestic or tame turkeys weigh twice what a wild turkey does and are raised on farms for profit.



Most domestic turkeys are so heavy they are unable to fly.



Wild turkeys (Meleagris gallopavo) live in woods in parts of North America and are the largest game birds found in this part of the world. They spend their days foraging for food like acorns, seeds, small insects and wild berries. They spend their nights in low branches of trees (yes, wild turkeys can fly!).



Peacocks aren’t the only birds who use their fancy tails to attract a mate. Each spring male turkeys try to befriend as many females as possible. Male turkeys, also called "Tom Turkeys" or "Gobblers" puff up their bodies and spread their tail feathers (just like a peacock).
They grunt, make a "gobble gobble sound" and strut about shaking their feathers. This fancy turkey trot helps the male attract females (also called "hens") for mating.
After the female turkey mates, she prepares a nest under a bush in the woods and lays her tan and speckled brown eggs. She incubates as many as 18 eggs at a time. It takes about a month for the chicks to hatch.



When the babies (known as poults) hatch they flock with their mother all year (even through the winter). For the first two weeks the poults are unable to fly. The mother roosts on the ground with them during this time.



Wild turkeys are covered with dark feathers that help them blend in with their woodland homes. The bare skin on the throat and head of a turkey can change color from flat gray to striking shades of red, white, and blue when the bird becomes distressed or excited. Have you ever wondered what Turkey (the country in the Middle East) and the American bird have in common? A case of mistaken identity resulted in the American Turkey being named after the country. When the Spanish first found the bird in the Americas more than 400 years ago they brought it back to Europe. The English mistakenly thought it was a bird they called a "turkey" so they gave it the same name. This other bird was actually from Africa, but came to England by way of the Turkey (lots of shipping went through Turkey at the time). The name stuck even when they realized the birds weren’t the same.
Who's a Turkey?
A construction crew in a pickup truck drove into a lumberyard. One of the new men walked in the office and said, "We need some four-by-twos."
The clerk asked, "You mean two-by-fours, don’t you?"
The man said, "I’ll go check with my boss," and went back to the truck. He returned and said, "Yeah, I meant two-by-four."
"All right. How long do you need them?"
The customer paused for a minute and said, "I’d better go check with my boss again."
After a while, the customer returned to the office and said,
"A long time. My boss says we’re gonna build a house."


Friday, August 29, 2008

More Nature Trivia


• A chameleon can move its eyes in two directions at the same time.


• A female mackerel lays about 500,000 eggs at one time.


• A leech is a worm that feeds on blood. It will pierce its victim's skin, fill itself with three to four times its own body weight in blood, and will not feed again for months. Leeches were once used by doctors to drain "bad blood" from sick patients.


• A polecat is not a cat. It is a nocturnal European weasel.


• Animal gestation periods: the shortest is the American opossum, which bears its young 12 to 13 days after conception.


• Beaver teeth are so sharp that Native Americans once used them as knife blades.• It takes a lobster approximately seven years to grow to be one pound.


• Moles are able to tunnel through 300 feet of earth in a day.


• The Canary Islands were not named for a bird called a canary. They were named after a breed of large dogs. The Latin name was Canariae insulae - "Island of Dogs."


• The fastest-moving land snail, the common garden snail, has a speed of 0.0313 m.p.h..


• The pygmy shrew—a relative of the mole—is the smallest mammal in North America. It weighs 1/14 ounce.


• There are around 2,600 different species of frogs. They live on every continent except Antarctica.


• Dragonflies have as many as 30,000 lenses in each eye. If you don't believe me, count them yourself.


• Insects with the fastest wing beat frequency are the no-see-ums, or very tiny midges, which beat their hairy wings 1,046 times per second. Male mosquitoes beat their wings 450 to 600 times per second.


• The fastest insect runners are cockroaches, which can move almost a foot per second. However this only translates to a little over 1 m.p.h..


• The loudest insects are male cicadas, which can be heard about a quarter of a mile away.

Armadillos Invade America


After years in south Georgia, where they are common road kill and a nuisance to some homeowners, armadillos have spread to the chillier northern half of the state where their digging and burrowing is already generating complaints.The official state mammal of Texas, armadillos invaded the Lone Star State from Mexico in the 1800s and have been spreading North and East ever since. Their name means "little armored thing" in Spanish. They don't displace other species or cause significant habitat changes, but their digging for grubs and other invertebrates can destroy a flower bed in a single night. Cattle and humans risk injury if they step into holes dug by the south American mammal, which is related to anteaters and sloths. On the plus side, armadillos eat lots of insects, including some that are pests. Joshua Nixon, a Michigan State University Zoologist, who has hosted an armadillo Web site since 1995 as a hobby, said he is not surprised that the burrowing mammals would spread to north Georgia, since they have already been confirmed in southern Illinois and he's received unconfirmed reports of them north of New York City and in the Pacific Northwest. Cold weather is about the only thing that restricts their spread. With limited fat reserves, they have to come out of their cozy burrows every couple of days for their meals, which would be impossible in extremely cold climates. Of course, sometimes it is the armadillos themselves that become the meals. During the Depression, when Herbert Hoover was president, armadillos were known as "Hoover Hogs" by the impoverished Americans who had to eat them, instead of the "chicken in every pot" he had promised. Some people still eat them, and the Internet is replete with recipes for such dishes as armadillo 'n rice, barbecued armadillo and armadillo fricassee. Despite their intolerance to cold, Nixon said he's surprised at how far and quickly they've spread. There is even evidence that they might hitch rides on trains, he said. "They're one of the few mammals that is spreading its range," Nixon said, noting that North America once had a native armadillo, known as the "beautiful armadillo," that went extinct about 50,000 years ago. The armadillo's tendency to leap when startled often means trouble on the highways. The maneuver helps the animal avoid predators, but often lands it on the grilles and undersides of cars and trucks. If they didn't have this nervous hic-up they would often survive crossing the road when a vehicle drove over them. Contrary to popular belief, the nine-banded armadillo cannot roll itself into a ball to escape predators. Also, Armadillos are not blind, but most of them do need glasses.

Wednesday, March 26, 2008

Factoids


• Precocial birds like chickens, ostriches, ducks, and seagulls hatch ready to move around. They come from eggs with bigger yolks than altricial birds like owls, woodpeckers, and most small songbirds that need a lot of care from parents in order to survive.
• There are only about 4,000 kinds of mammals. This sounds like a lot, but when you consider there are 21,000 kinds of fish and a whopping 800,000 kinds of insects you’ll realize mammals are a pretty small class!
• The Blue Whale, Balaenoptera musculus, is the largest mammal living today. It is also the largest mammal to have ever lived. In fact the Blue whale is the largest animal ever to have lived on the planet as far as we know; bigger by far than even the largest Dinosaur. The longest Blue Whale ever measured was a female, 110ft long. The heaviest weighed over 190 tons. We haven’t actually got a set of weighing scales big enough so weights are estimated from the cut up remains.
• Fish have been on the earth for more than 450 million years. Fish were well established long before dinosaurs roamed the earth. It is estimated that there may still be over 15,000 fish species that have not yet been identified. There are more species of fish than all the species of amphibians, reptiles, birds and mammals combined. About 40% of all fish species inhabit fresh water, yet less than .01% of the earth’s water is fresh water.
• Most reptiles are carnivores, and eat whole prey or insects. Some reptiles (adult green iguanas, for example), are herbivores and eat green plants. The shape of a reptile’s pupil indicates whether the animal is active at night or during the day. Most reptiles active at night have slitlike pupils that can be closed almost completely in bright light. Reptiles active in daytime have round pupils. Most reptiles have good vision, and some can tell the difference among colors.
• Amphibians include frogs, toads, salamanders and caecilians. The word means double life—many species spend part of their life in aquatic (water) and terrestrial (land) environments. Because their skin lacks a shell, scales or outer drier covering, most amphibians live in wet or damp situations to prevent dehydration.
• Teach, teach, teach-er is the song of the Ovenbird. Ovenbirds are found mostly in the Eastern parts of North America. The Ovenbird eats mostly insects and plant matter. Domed nests can be found on the ground or in deciduous and evergreen trees. A nest is shaped like an old-fashion oven.

• For more than 40,000 years before European navigators visited the shores of the Great South Land, Aborigines occupied Australia, including its arid deserts, tropical rainforests, coastal plains, mountains, and especially its major river systems. Estimates by anthropologists put the population of Australian Aborigines before 1770 at more than 300,000. They spoke 500 different languages grouped in thirty-one related language families.
Aborigines were completely at home in their surroundings and had no trouble "living off the land." This was mainly because of their intimate knowledge of the topography and natural resources of their tribal territories, and their complete understanding of the habits of the animals they hunted. The Australian aborigines extensively used insects from their surroundings as food, medicine, and as part of their cultural beliefs. However, most data concerning the use of insects by Australian Aborigines occur as scattered references in various anthropological, gastronomical, and pharmaceutical sources.
Insects have been consumed as food in many parts of the world, and insects consumed directly as food was probably the most important use of insects to the Australian Aborigines. An interesting example of mass harvesting of edible insects is the moth feasts that occurred in the Bogong mountains of New South Wales. The Bogong moth, Agrotis infusa, aestivated in large numbers every year in rock shelters of these mountains. From November to January, hundreds of Aborigines from different tribes would gather for huge feasts on these adult moths. Rock crevices were covered with layers of these moths, which were collected by dislodging and then collecting the moths from the cave of crevice floor. Moths were then cooked in sand and stirred in hot ashes, which singed off the wings and legs. Moths were then sifted on a net to remove their heads. In this state, they were generally eaten, although sometimes they were ground into a paste and made into cakes. As a food, the Bogong moth was rich in fat, with the average fat content of the male’s abdomens exceeding sixty-one percent, and of females, fifty-one percent of their dry weight.

Sunday, February 17, 2008

Bird Droppings

How Do Thousands Of Starlings Fly Without Colliding?
You’ve probably seen it and scratched your head in amazement—a massive flock of starlings, often just before sundown, darting around in the sky in an impossibly complicated pattern, like a school of sardines trying to evade a shark.
It’s likely you’ve wondered why the birds never crash into each other, or why no stragglers ever get left behind, or how the birds seem to always maintain their place despite the shifting shape and density of the flock.
Physicist Andrea Cavagna also asked those questions, probably getting a stiff neck from staring into the dusky sky over his native Rome, watching the birds overhead. He was so intrigued by the mystery, in fact, that he spent the past three years trying to crack the code.
Now, he is happy to report, he has the key to the puzzle. STARFLAG: Starlings in Flight—a collaboration of seven European institutes that he led under the direction of the Italian National Institute for the Physics of Matter—has come up with some answers.
What’s the starling secret?
The secret is that the starlings, whether there are 100 in the flock or 10,000, use a tracking system that helps them maintain their distance from the seven other birds around them, regardless of the distance between them.
If the flock is under attack from a predator—in Rome, for example, the birds are often targeted by Peregrine Falcons—they will spread apart. At other times, such as when the flock is making a tight maneuver or directional change, they will merge much more closely together.
"They do these incredible maneuvers but they never lose birds, they are always with the flock no matter how drastically they change the shape or the intensity, they always stay together."
After one year of studying the data collected in the two previous years of the study, Cavagna said the researchers have come to the conclusion the birds base every movement on what their wing-mates are doing.
"They always interact with six or seven birds irrespective of what is the distance of these seven birds," he says.
That means that after an attack has taken place, and the flock has expanded, it can regroup very quickly because cohesion doesn’t rely strictly on the distance between the birds.
Previous research held that each bird interacted with all other birds within a certain physical distance surrounding it.
Researchers collected their data in Rome, using cameras mounted on the roofs of buildings in neighborhoods where starlings often perform their aerial acrobatics.
The flocks were photographed at the same time by multiple cameras, using a rate of 10-frames-per-second.