Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen), usually entirely hidden under the thorax. They live in all the world's oceans, in fresh water, and on land. They are generally covered with a thick exoskeleton and have a single pair of claws. Many other animals with similar names – such as hermit crabs, king crabs, porcelain crabs, horseshoe crabs and crab lice – are not true crabs.

Crabs vary in size from the pea crab, a few millimeters wide, to the Japanese spider crab, with a leg span of up to 13 feet. Males often have larger claws. In most male crabs, the abdomen is narrow and triangular in form, while females have a broader, rounded abdomen. This is due to the fact that female crabs brood fertilized eggs on their legs.

Crabs attract a mate through chemical (pheromones), visual, acoustic or vibratory means. Pheromones are used by most fully aquatic crabs, while terrestrial and semi-terrestrial crabs often use visual signals, such as fiddler crab males waving their large claw to attract females. Many crabs have internal fertilization and mate belly-to-belly. For aquatic species, mating usually takes place just after the female has moulted and is still soft. Females can store the sperm for a long time before using it to fertilize their eggs. When fertilization has taken place, the eggs are released onto the female's abdomen, below the tail flap, secured with a sticky material. In this location they are protected during embryonic development. Females carrying eggs are called "berried" since the eggs resemble round berries.

When development is complete, the female releases the newly hatched larvae into the water, where they are part of the plankton. The release is often timed with the tides. The free-swimming tiny zoea larvae can float and take advantage of water currents.

Each species has a particular number of stages, separated by moults, before they change into a megalopa stage, which resembles an adult crab, except for having the abdomen (tail) sticking out behind. After one more moult, the crab is a juvenile, living on the bottom rather than floating in the water. This last moult must take place in a habitat that is suitable for the juvenile to survive.

Most species of terrestrial crabs must migrate down to the ocean to release their larvae; in some cases this entails very extensive migrations. After living for a short time as larvae in the ocean, the juveniles must do this migration in reverse.

Once crabs have become juveniles they still have to keep moulting many more times to become adults. They are covered with a hard shell, which would otherwise prevent growth. The moult cycle is coordinated by hormones. When preparing for moult, the old shell is softened and partly eroded away, while the beginnings of a new shell form under it. At the time of moulting, the crab takes in a lot of water to expand and crack open the old shell. The crab must then extract itself from the old shell. This is a difficult process that takes many hours, and if a crab gets stuck it will die. After freeing itself from the old shell the crab is extremely soft and hides until its new shell has hardened. While the new shell is still soft, the crab can expand it to make room for future growth.

Crabs typically walk sideways. However, some crabs walk forwards or backwards. Some crabs are also capable of swimming.

Crabs are active, complex animals. They can communicate by drumming or waving their pincers. Crabs tend to be aggressive towards one another and males often fight to gain access to females. On rocky seashores, where nearly all caves and crevices are occupied, crabs may also fight over hiding holes. Fiddler crabs dig burrows in sand or mud, which they use for resting, hiding, mating and to defend against intruders.

Crabs are omnivores, feeding primarily on algae, and taking any other food, including molluscs, worms, other crustaceans, fungi, bacteria and detritus, depending on their availability and the crab species. For many crabs, a mixed diet of plant and animal matter results in the fastest growth and greatest fitness. However, some species are more specialized in their diets. Some eat plankton, some eat primarily shellfish like clams, and some even catch fish.

Crabs are known to work together to provide food and protection for their family, and during mating season to find a comfortable spot for the female to release her eggs. They will help other crabs fight off intruders. Neighboring crabs never fight with each other.

Many mother crabs provide loving care for their babies. Mothers continue to feed and tend to their babies for several months after they are born. They work hard to keep their homes clean and comfortable for their young.

Crabs are intelligent animals, capable of learning from their mistakes and retaining that information so they don’t make the same mistakes again. They adapt to changing cues in their environment.

Crabs are threatened with declining habitats, pollution, overfishing and the declining abundance of coral reefs. Crabs make up 20% of all marine crustaceans caught, farmed, and consumed worldwide, amounting to 1½ million tons annually. In some species, crab meat is harvested by manually twisting and pulling off one or both claws and returning the live crab to the water in the belief the crab will survive and regenerate the claws thereby making it a sustainable industry. Crabs are often inhumanely boiled alive. Crustaceans are able to feel and remember pain. They fight so hard against a clearly painful death that their claws often break off in their struggle to escape. Some crabs used for food are electrocuted, some are chopped up, and others are microwaved—all while they are still conscious.

Hammerhead sharks, which belong to the family Sphyrnidae, are some of the most unique looking creatures in the ocean. There are ten distinct species of these sharks, which most people recognize by their distinctive head shape; a flattened, extended structure that’s called a cephalofoil. (A related and slightly different hammerhead species, the winghead shark, is classified under the family name Eusphyra instead.)

Hammerhead sharks tend to prefer warm water living, so they’re usually found in ocean habitats that are close to coastlines and continental shelves – they’ve been found in the Gulf of Mexico and off the Californian coast, as well as in Colombian, Costa Rican, Hawaiian, Australian, and southern and eastern African coastal waters. Depending on the year and weather phenomena such as El Niño conditions, some hammerheads may migrate seasonally, swimming towards warmer waters closer to the equator in the winter and northward towards the poles in the summer.

These large sharks can grow to quite a significant size, depending on their age and sex. The largest species, the great hammerhead, can range from 3 feet to over 19 feet in length, and may weigh from 6.6 to as much as 1,278 pounds. Other species of hammerheads are usually much smaller, however, and all species of hammerheads have an average lifespan of 25 to 35 years.

They’re light in color with a tall, straight dorsal fin, and their slight green skin tint and white underbelly allows them to blend well into the ocean and sneak up on prey below.

A hammerhead’s head shape, of course, is the most interesting part of their anatomy; their heads have flat projections that extend out on either side, with their eyes actually placed on either side of the hammer shape at the outer edges allowing them a 360 degree view of what’s above and below them at all times.

All sharks have special sensory pores that detect the tiny electrical fields made by other animals (called ampullae of Lorenzini), but on a hammerhead shark, these pores are spread out over a wider area giving them a larger advantage when sweeping for their next meal to eat.

Typically, hammerheads have a smaller mouth than other sharks, hunting mainly close to the bottom of the ocean. Some species (like the scalloped and smooth hammerhead) travel in schools with other hammerheads during the day, though they separate themselves to hunt alone at night.

Hammerheads are efficient and carnivorous ocean hunters that eat a range of different prey, including fish, squid, octopus, crustaceans, and sometimes other sharks. Their favorite food, however, is stingrays, which they stalk and pin down with their mallet-shaped head. Great hammerhead sharks are more likely to occasionally eat other hammerheads, including their own young on occasion.

Reproduction can also be a rather dangerous business for hammerhead females. Usually happening only once a year, a female shark is persuaded to mate with a male hammerhead by violent episodes of biting until she agrees to the coupling. After sperm is transferred to the female, eggs are fertilized inside her and embryos begin to develop, at first being nourished only by a yolk sac. After the yolk is gone, however, the sac then transforms into a structure that resembles a mammal’s placenta, allowing the young sharks to be sustained by the mother’s body until they’re developed enough to be born. At this point, the mother can give birth to  a litter of 12 to 15 live shark pups (great hammerheads can birth up to 40 pups), which tend to be born in the spring or summer months, and stay together for protection and safety as they swim for warmer, shallower waters. Neither of the shark parents provides any further care to the pups after birth.

As for their threat to people, most hammerheads are harmless, and only three hammerhead species have been noted as being dangerous at all. Scalloped, great, and smooth hammerheads have been known to attack humans, but there are no listed deaths on record for a hammerhead attack against a person.

Unfortunately for these fascinating fish, we humans are their largest threat. Overfishing and the shark fin trade (where a shark’s fins are harvested as a delicacy, but the remainder of the shark is thrown back into the ocean) have put some hammerhead species at risk of extinction.

Two species, the great and scalloped hammerhead, are listed by the World Conservation Union as endangered, and the smalleye hammerhead has a ‘vulnerable’ status.

Interestingly, Hawaii may be one of the safest places for hammerhead sharks to exist at the moment. Native Hawaiian culture reveres sharks, believing some species to be reincarnated family members or the chosen ‘birth animals’ for some children, and the hammerhead shark in particular is seen as a highly respected animal and a good omen.

The fennec fox is a small fox found in the Sahara Desert of North Africa (excluding the coast) which has distinctive oversized ears. The fennec is the smallest canid. The animals are often a sandy color and blend in with their desert surroundings. Their ears, which are the largest in the canid family, serve to help dissipate heat. Their coat can repel sunlight during the day and conserve heat at night. The soles of of a fennec's feet are protected from the hot sand by thick fur.

The fennec fox is nocturnal. During the night, they will hunt for rodents, insects (such as locusts), lizards, birds and eggs. Fennec foxes gets most of their water from food, but will sometimes eat berries and leaves as an additional source of water.

Fennecs live in large dens, often with several foxes. The basic social unit is thought to be a mated pair and their offspring, and the young of the previous year are believed to remain in the family even after a new litter is born. Playing behavior is common, including among adults of the species.

Fennecs engage in highly social behavior, typically resting while in contact with each other. They mate for life, with each pair or family controlling their own territory. Sexual maturity is reached at around nine months old. The species usually breeds only once each year. The copulation tie has been recorded as lasting up to two hours and 45 minutes. Following mating, the male becomes very aggressive and protective of the female, providing her with food during her pregnancy and lactation periods. Gestation is usually between 50 to 52 days. The typical litter is between one and four kits, with weaning taking place at around 61 to 70 days. When born, the kit's ears are folded over and their eyes are closed, with the eyes opening at around ten days and the ears lifting soon afterwards. The life span of a fennec fox has been recorded as up to 12 years in captivity, and up to 10 years in the wild.

The fennec is rare and is not often seen. They are often hunted by humans, even though the fox does not cause any harm to human interests.

Fennecs are common victims of the animal entertainment industry. They are often found on display at zoos, roadside zoos and "wildlife safaris". Like all captive wildlife, they face constant stress and are denied their wild nature, strong family bonds and natural social interactions. The needs and desires of humans comes before the needs of the animals in the animal entertainment industry.

Highly intelligent and social animals, they also suffer terribly in the inhumane pet trade. Sold like toys by unethical businesses and backyard breeders, profit is put above the welfare of the animals. Unprepared guardians purchase the animals, often with little knowledge on their care. Their complex physical, psychological and social needs can never be met when they are kept as pets.

Sharks are members of a group of almost exclusively marine and predaceous fishes. There are about 250 species of sharks, ranging from the 2 feet pygmy shark to 50 feet giants. They are found in all seas, but are most abundant in warm waters. Some may enter large rivers, and one ferocious freshwater species lives in Lake Nicaragua. Most are predatory, but the largest species, the whale shark and the basking shark, are harmless plankton eaters. Dogfish is the name for members of several families of small sharks; these should not be confused with the bony dogfishes of the mud minnow and bowfin families.

Sharks are heavy fishes, possessing neither lungs nor swim bladders. Their skeletons are made of cartilage rather than bone, and this, along with large deposits of fat, partially solves their weight problem. Nevertheless, most sharks must keep moving in order to breathe and to stay afloat. They are good swimmers; the wide spread of the pectoral fins and the upward curve of the tail fin provide lift, and the sweeping movements of the tail provide drive. Their tough hides are studded with minute, toothlike structures called denticles. Sharks have pointed snouts. Their crescent-shaped mouths are set on the underside of the body and contain several rows of sharp, triangular teeth. They have respiratory organs called gills, usually five on each side, with individual gill slits opening on the body surface. These slits form a conspicuous row and lack the covering found over the gills of bony fishes.

Like most fishes, sharks breathe by taking water in through the mouth and passing it out over the gills. Usually there are two additional respiratory openings on the head, called spiracles. A shark's intestine has a unique spiral valve, which increases the area of absorption. Fertilization is internal in sharks; the male has paired organs called claspers for introducing sperm into the cloaca of the female. Members of most species bear live young, but a few of the smaller sharks lay eggs containing much yolk and enclosed in horny shells. Compared to bony fishes, sharks tend to mature later and reproduce slowly.

Only a small number of the predatory species are definitely known to occasionally engage in unprovoked attacks on humans. The largest and most feared of these is the great white shark, which may reach 20 feet in length and is probably responsible for more such attacks than any other species. Other sharks reputed to be slightly dangerous are the tiger and blue sharks and the mako. Sharks are extremely sensitive to motion and to the scent of blood. Swimmers in areas where dangerous varieties occur should leave the water quietly if they are cut. In some places bathing areas are guarded by nets. A number of substances have been used as shark repellents, but their effectiveness is variable. Sharks usually circle their prey before attacking. Since they seldom swim near the surface, an exposed dorsal fin is more likely to be that of a swordfish or ray than that of a shark.

Sharks can range from being just inches in length (like the tiny cookie cutter shark) to being larger than a school bus (like the giant plankton-eating whale shark). Though sharks perform the same role in the ocean ecosystem that is performed by well-known predators such as lions, tigers, and cheetahs on land, the fact that they live in such an alien world makes it hard for us to know about their lives. What we do know is pretty fascinating.

Sharks shed their teeth. A single shark may lose thousands of teeth over its life and this accounts for the many shark teeth found by beach combers throughout the world. Their teeth are connected to a membrane in their mouth that is constantly being pushed forward as new teeth form. New teeth are generally slightly larger than the ones before. This allows the size of the shark's teeth to keep pace with the growth of the rest of the body.

Sharks are picky eaters. Some sharks eat only plankton, others eat small fish or squid, and still others eat large fish and marine mammals. The type of teeth a shark has will show you what it eats. Great white sharks have teeth with serrated edges for slicing off pieces from larger prey, the teeth of mako sharks are thin and pointed for grabbing onto slippery fish. Nurse sharks and other bottom dwellers tend to have thicker teeth for crushing shellfish. No matter the tooth shape, sharks never chew their food.

You're more likely to die as a result of being electrocuted by holiday lighting than being attacked by a shark. More deadly than shark attacks each year are crocodile attacks, hippo attacks, and even attacks by pigs.

Many sharks are warm blooded. Unlike the rest of the fishy world, many large sharks can maintain their body temperature higher than the ocean temperature around them. We don't know whether sharks sleep. Sometimes they seem to rest, but their eyes don't close and if they sleep, they certainly don't sleep the way that mammals can.

Don't be afraid OF sharks; be afraid FOR them. There are more misunderstandings and untruths about sharks than almost any other group of animals on the planet. While many people fear sharks, it is the sharks who should be fearing us.

According to the shark attack file, maintained by the Florida Museum of Natural History, on average 5 people die worldwide from shark attacks. Up to 70 million sharks are killed by humans each year, mostly for their fins. This is a devastating death toll for a long-living species that is as slow to reproduce as sharks.

Sharks have roamed the oceans far longer than most land animals have been here. They were here before many of the dinosaurs and have outlasted them. But an international assessment of sharks undertaken by the World Conservation Union reveals that their future is in doubt. Of 546 shark species assessed, 111 species were at significant risk of global extinction. Twenty species are listed as critically endangered and 25 as endangered. Some shark species have lost 80% of their populations just in the past 40 years including hammerhead sharks, thresher sharks, and porbeagle sharks. While hammerhead shark is a name familiar to most, most people have never heard of porbeagle sharks; some of the lesser known sharks are in even greater danger.

There is a lot we don't know about sharks, but we DO know that if we don't act soon to stop overfishing, some of the most ancient and magnificent animals on the planet may soon disappear.

Members of one of the most diverse groups of lizards, skinks are reptiles with cylindrical, streamlined bodies, functioning eyelids and tight, smooth, scaly skin. They belong to the family Scincidae, and their name comes from the Greek word skinkos, which was a name that was used to refer to lizards in a specific region of the country. Over 1500 distinct species of skinks have been described, living in a wide range of habitats worldwide, from dry deserts, to mountains, grasslands and forests.

Although skinks are close in appearance to ‘true lizards’ (such as wall lizards, for example), they don’t have a distinct neck, and their legs tend to be smaller. Interestingly, some species of skink actually have reduced limbs or even no limbs at all, making their movement appear far more like a snake than a lizard - which is what many people may mistake them for. A few certain skink species, like the blue-tongued skink, also tend to be more broad-headed and wider-bodied than their relatives.

The particular living environment of a skink can often be determined merely by its toe length – generally, the longer a skink’s digits (toes), the more likely it is to spend most of its time climbing in trees.

These unusual reptiles tend to be small to medium sized, on average, depending on the species. They can range from specimens as tiny as the little brown skink at 3 inches, to as large as the Solomon Islands skink at 14 inches, though their tails usually make up more than half of that length.

Many skink species are escape artists. They can shed their tails when necessary if predators grab them, and can re-grow the lost part. The shed tail will actually wiggle for a short period of time after being lost, which serves to distract any potential predators while the skink makes its escape. Skinks may also return to the lost tail and ingest it in order to regain lost nutrient value.

Active, quick, and agile little lizards, skinks can dart rapidly from place to place when they’re not found basking on warm rocks or logs. Offspring-bearing females or mating pairs tend to be slower, however. Some species of these lizards are tree-climbing, but for the most part, most tend to live in ground habitats (so they’re terrestrial, in other words), or prefer to burrow through sand. They’re most active in the daytime.

Skinks like to stay safe and out of the reach of predators or bad weather, and make their nests in secure, hidden areas. For some, this can mean a nest in the dirt or under heavy brush cover. For other skinks (especially those in and around urban areas) rotting boards, garages or spaces under structures like sheds can be suitable nesting areas. Some nests can contain anywhere from 10 to 30 skinks at a time, and it’s not unusual for skinks to actually ‘guard’ their territory. A small number of skink species are also water-dwelling, but these tend to be the exception.

Skinks are fairly predictable eaters. Being carnivorous lizards, their menu choices tend to run to insects like flies, beetles and caterpillars, but some may even eat snails or small rodents. They sniff out prey using their tongue, and then chase it down, corner it, and usually swallow it whole.

The method of producing young can be different from species to species of skink. Male skinks will sometimes fight each other for the privilege of mating with a certain female by biting each other on the head, neck or tail. Male-female pairs in some species will form monogamous relationships from year to year. Just under half of all skink species birth live young, nourishing their offspring though a placenta-like organ. Other species hatch their eggs internally instead, and then give birth to young after that. Still others lay eggs which hatch outside their body.

Females tend to be protective of their eggs, coiling around them and guarding against predators, and will often stay to protect their new offspring for the first few days until they leave the nest. Skinks can have significant gestation times, typically several months and as long as one year in some species. They have been noted to have as few as 1 or as many as 67 young born at one time.

Although many skinks are highly adaptable when it comes to their nesting situation, they also have a large number of natural predators. Raccoons, snakes, crows, herons, hawks and other lizards may see skinks as a tasty meal.

Because the skink’s long gestation period means that they can’t replenish their population numbers as quickly as other animals, overhunting by larger invasive predators like the mongoose has caused skink species in some areas to approach extinction. The Anguilla Bank skink in the Caribbean is one example.

Birds are warm-blooded, covered in feathers and lay eggs. All birds have wings, a beak and stand on two legs. Most birds fly, but some cannot. Some species, particularly penguins and members of the Anatidae family, are adapted to swim. Some birds eat only seeds and berries. Some also eat insects. Birds of prey eat small animals. Male birds are usually more brightly colored than females, while females have better camouflage which helps to protect their nests.

Birds are incredibly intelligent animals. They make and use tools and culturally transmit knowledge across generations. They are social, communicating with visual signals, calls and songs, and participate in such social behaviors such as cooperative breeding and hunting, flocking and mobbing of predators. The vast majority of bird species are monogamous, for one breeding season or for years. Eggs are usually laid in a nest and incubated by the parents. Most birds have an extended period of parental care after hatching. In some species, both parents care for the babies, or close relatives will help with the raising of the young.

Birds are present in almost all habitats on earth and are usually the most familiar and visible wildlife to people all over the world. Because of this, they may act as a significant indicator for monitoring how the biosphere changes. Diminishing bird populations in the majority of habitats are the sad confirmation that major changes are taking place on Earth because of our activities. More than 12% of currently known species of birds are at the threshold of extinction. The biggest impact on bird population has been caused by degradation and loss of habitat, with collectors’ activities and invasive species following closely.

The tallest bird is the ostrich at around 9 feet tall. The ostrich is also the heaviest bird, at about 345 pounds. The heaviest flying bird is the mute swan at about 40 pounds. The largest wingspan of all birds belongs to the wandering albatross at 11 feet 10 inches.

The smallest bird is the bee hummingbird measuring in at only 2.2 inches from beak to tail.

The fastest bird is the spine-tailed swift, traveling at speeds of over 106 mph.

The longest living bird is thought to be the sulfur-crested cockatoo, able to live well into their 80's.

Crows’ intelligence rivals human children. They use tools to get food, have exceptional memories and anticipate future events to help them solve problems. They have learned to use bread crumbs as fish bait. They can count, distinguish complex shapes and perform observational learning tasks. Crows are extremely social creatures. They have been observed creating knives from leaves and stalks of grass and using advanced plucking, smoothing and bending to fashion twigs and grass into a variety of substances. Caledonian crows remember specific people, cars and urban situations. They also develop grudges against specific people and cars that last for years.

Ravens push rocks on people to keep them from their nests, steal fish by pulling a fishermen’s line out of water and play dead beside an animal carcass to scare other ravens away from the food. Ravens are known to steal food from other birds and mammals. They can act in pairs: one individual captures an animal's attention, while the other steals its food. They pretend to hide food in one place while really hiding it somewhere else to fool other animals. Ravens can learn to talk better than many parrots and mimic other noises. They imitate wolves or foxes to attract them to carcasses that the raven cannot break open. They roll around in anthills so the ants swarm on them, or they chew the ants up to rub their guts on their feathers as an insecticide and fungicide or to soothe molting skin. Ravens point with their beaks to indicate an object to another bird and hold up objects to get the attention of other birds. They will console other birds and remember friends and family for years. They live complex social lives and express happiness, tenderness, surprise, emotion and rage through their own language. Ravens are very playful and play with other ravens, other animal species and humans. They mate for life and live in pairs. When children reach adolescence, they join gangs until they mate and pair off.

Many birds have been known to play. Ravens and crows love to play and have been observed sliding down snow banks on their backs, cavorting in updrafts and sliding repeatedly down sloping church windows.

Jay birds have been observed grieving, including an entire group of birds sitting for 48 hours near a dead brethren.

Swans are highly intelligent and social animals. They remember who have been kind to them, and who have not. They usually only show aggression to those who have upset them, and will remember them. They have sharp vision and hearing and use a remarkable assortment of sounds to convey a broad range of emotions. Swans usually mate for life, with occasional “divorces” occurring. Male swans will occasionally baby sit an egg so the expecting mother can take a break.

Pigeons are actually domesticated rock doves who were set free. They are marvelous parents: the father builds the nest, and both parents take turns incubating the eggs and even making milk in their crops for the young. Pigeons remember dozen of routes to find their way to familiar places, and can recognize their faces in mirrors. They can remember hundreds of photographs and images, are able to differentiate between photographs, and even differentiate between different human beings in a photograph. They have been known to be able to distinguish between Van Gogh and Chagall paintings. They can count, order items in ascending order and understand math rules. They have an amazing ability to remember people and places throughout the course of their life. Pigeon can recognize all 26 letters of the English language, be taught complex actions and response sequences, and can make responses in different sequences.

It has been discovered that birds name their offspring. They use smell memories to travel thousands of miles. They show advanced planning and art. They have been proven to perform arithmetic, invent words and express love through language.

Parrots not only mimic the words of humans, they also understand the meanings of the words. Studies show that they remember 90% of what they are told, including full sentences and even parts of songs. They are capable of performing math, identifying colors and communicating to humans what they want. Parrots cannot bear to be alone. While most mate for life, all live in large social groups, sometimes with multiple species of birds.

Ostrich mothers lay their eggs in a communal nest, allowing the eggs and young to all be cared for by one bonded pair; up to 380 chicks have been seen being escorted by loving parents.

Finches learn by listening to others and follow rules of syntax. Bengal finches use strict rules of syntax. If a zebra finch is sick, it will fake being healthy in front of other zebra finches, especially if there’s a chance to mate.

 

Watching the many species of birds that inhabit your ecosystem is a fun and fascinating pastime the whole family can enjoy together. Winter is the best time to feed birds as they need the food more than at any other time of year and you will typically see a greater number and variety of birds at bird feeders. Many interesting birds from the north fly south in winter, and in spring many species return home from lands in the south, providing a great variety of species to see.

 

You don’t need to spend money on food or feeders to attract birds to your yard. If you can leave a small area of your yard un-mowed, you can attract a lot of birds. They eat the seeds from the grasses and weeds and use the area for cover as well.

 

Employing a feeder grants the ability for close study of birds. While all feeders draw birds, those that keep the bird feed dry and free of mold are best. Moldy seeds are bad for bird health. Place feeders either near a window or fairly far away to help prevent birds from colliding with windows when startled. The most common feeder is a hopper or house feeder, usually made of windows of clear plastic that feed seed to a perching surface. These feeders attract cardinals, nuthatches, chickadees, grosbeaks, buntings and titmice. One without a lot of perching surface minimizes use by house sparrows or starlings. The most important thing is to keep feeders clean by washing with bleach water every few weeks. Washing with bleach water prevents the spread of disease.

 

Although slightly more expensive, bird food with black oil sunflower seeds attract a wide variety of desirable birds. A suet feeder attracts woodpeckers, nuthatches, chickadees and bluejays. Some birders push suet or peanut butter into crevices in bark or in the cracks of old stumps to attract birds. Witnessing a northern flicker or red-bellied woodpecker feeding at close range sears a delightful memory into the mind of a youngster. Woodpeckers love dead branches on trees. Leave a dead branch on a tree to attract woodpeckers if it is safe to do so.

 

It is important to provide water for birds in winter too. Place the water in a spot in the yard that receives sun as its rays will melt some water for birds on even the coldest days.

 

A good guide book is essential for identifying birds. Looking up unfamiliar birds and learning about their distinguishing characteristics is part of the fun of birding. Modestly priced binoculars now have coated lenses and other features that make them acceptable choices for bird watching. Don’t get zoom binoculars for birding. You tend to lose clarity at high magnification. A wide angle pair lets in more light and makes it easier to find birds.

 

Bird watching is a good way to introduce kids into the outdoors and spark awareness of our natural world. Backyard birding is a family-friendly way to enjoy wildlife viewing. Plus, it is just plain fun.

Known for their highly effective and tremendously pungent defensive tactics, skunks are some of the most infamous animals around. Members of the family Mephitidae, the name of these distinctive little mammals likely originated from 1600’s Algonquian language. Although they can vary in appearance, almost all species of skunks are found in the Americas (ranging from Canada to central South America), with the exception of Asian stink badgers, which are generally found in Indonesia and the Philippines.

Differing in size and weight depending on species, these odiferous creatures can range from around 15 to 37 inches in length and weigh from around 1lb up to around 18 lb in weight – on average, around the size of a typical housecat. Although they’ve been known to live as long as 10 years in captivity, most skunks in the wild don’t live past the age of one or two, since many fall victim to pest control campaigns or collisions with vehicles because of their poor vision. They’re generally thickly furred and short-limbed with fairly compact bodies, including well-muscled forelegs and sharp claws that are well suited to digging for food or building burrows in the earth. Although skunk coat patterning and coloration is unique to specific species, every skunk is striped from birth, acting as a built in visual warning for predators who might consider the skunk an easy meal. Most skunk species are typically black and white, but coat colors for certain species might include brown, grey, or even cream colored. Some even have a series of spots and stripes combined, or stripes on their legs as well.

The scent of a skunk is its most renowned characteristic, as well as being one of the most effective existing defensive tactics within the animal kingdom. Skunks produce a very obnoxiously scented mixture of chemical oils within two small organs known as anal glands, found on either side of their anus. Strong muscles beside these glands allow a skunk to accurately spray their target as far as 10 feet away. As well as being extremely repulsive; skunk spray is extremely irritating and can even cause temporary blindness in some cases. Because these glands only produce a limited amount of spray, skunks are usually reluctant to use their spray as an initial protection, so they’ll go through a warning routine of foot-stamping, hissing and tail flagging postures before resorting to spraying as a last resort defence. The pungency of skunk spray is so strong that skunks are often able to deter bears and other predators from attacking them, and most people can smell a skunk from as far as ½ a mile away.

Because of their tenacious nature when survival is on the line, it’s not surprising that many skunks have learned to live and thrive in urban environments. Besides being omnivorous, these unique animals are opportunistic foragers and occasional scavengers, changing their diet with the availability of their food. They’ll use their sharp claws to dig holes in search of food, and a meal for a skunk might range from berries, leaves and grasses to insects, bees, worms or grubs. Some skunks may also eat lizards, frogs, snakes, moles, birds and bird eggs, as well as pet food and human refuse if available.

Not usually seen during daylight hours, skunks are most active at dawn and dusk, usually preferring to forage alone assisted by their highly developed senses of smell and hearing. Daylight means rest time for these small creatures, and they tend to shelter in self-made burrows until the sun sets. In colder weather, they’ll stay in their dens for increased periods of time, and groups of female skunks usually like to winter together to stay warm. They aren’t true hibernators, as they will emerge from their den during winter, but they do enter a more dormant phase feeding only occasionally and staying fairly inactive.

Like many other mammals with less active winter cycles, these small creatures mate in early spring and typically give birth to litters of four to seven kits around two months later. Males generally mate with more than one female to ensure successful genetic distribution. Skunk kits are born helpless, blind and deaf, and stay in the den for the first several weeks as they nurse from their dam. Male skunks don’t play any part in the raising or care of their kits. Around the age of three weeks, their eyes open, and around the age of two months, they become weaned and leave the den, though they tend to stay with the female until they’re sexually mature which happens around one year of age. Skunk mothers are particularly protective, too; a female who senses any threat to her kits won’t hesitate to spray potential predators.

Despite their smelly defences, there are still one or two predators who dare to hunt these small striped opponents. Domestic dogs tend to be the most numerous predators, with some even hunting skunks repeatedly despite retaliation. Wolves and other wild canids rarely hunt skunks themselves unless they’re desperate for food. The great horned owl is a skunk’s only consistent predator, swiftly killing them from the air and bringing them back to their nests to feed.

Although most skunk species are fairly populous, there are a variety of hazards that pose a danger to them. One species in particular, the Eastern Spotted skunk, is currently listed as endangered is some states because of population decline due to farming practices that eliminate ground cover. Some species have traditionally been hunted to harvest their pelts, while pesticide use in many areas has decreased the food supply that’s available for skunks. As a skunk’s foraging nature often leads it to roam across roads in search of food, collision with moving vehicles is a common occurrence for almost all skunk species.

The wolverine, also referred to as glutton, carcajou, skunk bear, or quickhatch, is the largest land-dwelling species of the family Mustelidae (weasels). It is a stocky and muscular carnivore, more closely resembling a small bear than other mustelids. The wolverine, a solitary animal, has a reputation for ferocity and strength out of proportion to its size, with the ability to kill prey many times larger than itself.

The wolverine can be found primarily in remote reaches of the Northern boreal forests and subarctic and alpine tundra of the Northern Hemisphere, with the greatest numbers in northern Canada, the U.S. state of Alaska, the Nordic countries of Europe, and throughout western Russia and Siberia. Their populations have experienced a steady decline since the 19th century in the face of trapping, range reduction and habitat fragmentation, such that they are essentially absent in the southern end of their European range.

The wolverine is a stocky and muscular animal with short legs, broad and rounded head, small eyes and short rounded ears. The adult wolverine is about the size of a medium dog. The males are as much as 30% larger than the females and can be twice the females' weight. Wolverines have thick, dark, oily fur, making them resistant to frost. A light-silvery facial mask is distinct in some individuals, and a pale buff stripe runs laterally from the shoulders along the side and crossing the rump just above a bushy tail. Some individuals display prominent white hair patches on their throats or chests.

Like many other mustelids, it has potent anal scent glands used for marking territory and sexual signaling. The pungent odor has given rise to the nicknames "skunk bear" and "nasty cat." Wolverines, like other mustelids, possess a special upper molar in the back of the mouth that is rotated 90 degrees, towards the inside of the mouth. This special characteristic allows wolverines to tear off meat from prey or carrion that has been frozen solid.

The wolverine is a powerful and versatile predator and scavenger. Prey mainly consists of small to medium-sized mammals, but the wolverine has been recorded killing prey such as adult deer that are many times larger than itself. Prey species include porcupines, squirrels, beavers, marmots, rabbits, voles, mice, shrews, lemmings, caribou, roe deer, white-tailed deer, mule deer, sheep, moose, and elk. Smaller predators are occasionally preyed on, including martens, mink, foxes, Eurasian lynx, weasels, and coyote and wolf pups. Wolverines often pursue live prey that are relatively easy to obtain, including animals caught in traps, newborn mammals, and deer (including adult moose and elk) when they are weakened by winter or immobilized by heavy snow. Their diets are sometimes supplemented by birds' eggs, birds (especially geese), roots, seeds, insect larvae, and berries. A majority of the wolverine's sustenance is derived from carrion, on which they depend almost exclusively in winter and early spring. Wolverines may find carrion themselves, feed on it after the predator is done feeding (especially wolf packs) or simply take it from another predator. Whether eating live prey or carrion, the wolverine's feeding style appears voracious, leading to the nickname of "glutton". However, this feeding style is believed to be an adaptation to food scarcity, especially in winter.

Armed with powerful jaws, sharp claws, and a thick hide, wolverines, like most mustelids, are remarkably strong for their size. They may defend kills against larger or more numerous predators such as wolves or bears. Wolverines are known to follow wolf and lynx trails with the intent of scavenging the remains of their kills. Wolves are thought to be their most important natural predator, with the arrival of wolves to a wolverine's territory leading them to abandon the area.

Wolverines inhabiting the Old World hunt more actively than their North American relatives. This may be because competing predator populations in Eurasia are not as dense, making it more practical for the wolverine to hunt for itself than to wait for another animal to make a kill and then try to snatch it.

Successful males form lifetime relationships with two or three females, which they will visit occasionally, while other males are left without a mate. Mating season is in the summer, but the actual implantation of the embryo in the uterus is stayed until early winter, delaying the development of the fetus. Females will often not produce young if food is scarce. The gestation period is 30–50 days, and litters of typically two or three young ("kits") are born in the spring. Kits develop rapidly, reaching adult size within the first year of a lifespan that may reach anywhere from five to 13 years. Fathers make visits to their offspring until they are weaned at 10 weeks of age; also, once the young are about six months old, some reconnect with their fathers and travel together for a time.

The world's total wolverine population is not known. The animal exhibits a low population density and requires a very large home range. The range of a male wolverine can be more than 240 square miles, encompassing the ranges of several females which have smaller home ranges of roughly 50 to 100 square miles. Adult wolverines try for the most part to keep non-overlapping ranges with adults of the same sex.

Female wolverines burrow into snow in February to create a den, which is used until weaning in mid-May. Areas inhabited non-seasonally by wolverines are thus restricted to zones with late-spring snowmelts. This fact has led to concern that changes in climate will shrink the ranges of wolverine populations.

Their requirement for large territories brings wolverines into conflict with human development, and hunting and trapping further reduce their numbers, causing them to disappear from large parts of their former range. Attempts to have them declared an endangered species have met with little success.

Barracudas are a large species of fish that live in the warmer, coastal regions of the planet's oceans. They are known for their aggressive and dominant predator behavior. There are over 20 species of barracuda in the world.

While barracudas are widely spread across the seas, they are more commonly found in tropical areas where there is an abundance of food sources. Although barracudas also live in the deep ocean, they prefer the coastal areas along continental shelves and near coral reefs. Barracudas are nocturnal animals, active during the night.

All species of barracuda have an elongated shape and a pointed head with powerful jaws housing sharp, fang-like teeth. Different species of barracudas vary in sizes and colors. Barracudas can grow to be very large. The upper part of a barracuda body is covered with scales that can be black, gray, brown or blue. A barracuda's belly is always white. Irregular dark spots are located on both sides of the barracuda's body.

Barracudas are carnivores. The barracuda feeds mainly on smaller species of fish, crustaceans, invertebrates and squid. They are opportunistic predators, feeding on other animals in the surrounding area. They use a surprise tactic to capture their prey, ambushing with tremendous power. They can swim very quickly in short bursts to overtake their prey.

Barracudas prefer a solitary life, but sometimes gather in groups called schools. Schools provide safety and cooperative hunting opportunities.

Barracudas have few natural predators. Sharks and killer whales prey on barracudas.

Mother barracudas spawn during the spring. The female barracuda releases her eggs into the ocean which are then fertilized externally by the male barracuda. Baby barracudas have little interaction with their parents.

Barracudas can live over 15 years in the wild.

The biggest threats to barracudas are recreational fishing and the barracuda meat trade.

All ocean animals are threatened by pollution, the fishing industry and changes in climate. Global fish populations are collapsing, affecting all marine life. Plastics and toxic waste are destroying aquatic ecosystems. Almost half of all ocean pollution is from irresponsible human activities that take place on land, including animal agriculture, sewage, chemical spills, industrial runoff and garbage dumping.

Marine habitats are being destroyed by coastal pollution. The clearing of mangrove forests and scraping of underwater mountain ranges through deep-sea trawling are also having detrimental affects on marine ecosystems.

Reptiles are cold blooded animals, covered with scales, and mostly lay eggs. Some reptiles eat plants, some eat animals and some eat both.

Reptiles are tetrapod vertebrates, meaning they have four limbs or, like snakes, they descended from four limbed ancestors. They usually have limited means of maintaining a constant body temperature and rely on external sources of heat. Being cold blooded requires far less fuel to function. A crocodile needs a fraction of the food a lion of the same weight needs, and can live half a year without eating. Due to their slow metabolism, reptiles can do well in areas where food sources are too low for most mammals and birds to live.

Four major groups of reptiles include crocodilians, snakes, turtles, lizards and ttuatara – a lizard-like reptile that is the only surviving member of an order which flourished around 200 million years ago. The study of reptiles, historically combined with that of amphibians, is called herpetology.

Reptiles lay eggs on land, and the eggs musts stay dry. Many reptiles bury the eggs. Mother pythons, mud snakes and some skinks wrap their bodies around their eggs to protect them. Alligator mothers carry newly hatched babies in their mouths. Some reptiles abandon their eggs and do not care for the babies. About a fifth of snake species give birth to live young. Warmer egg temperatures produce females for some turtles, cooler temperatures result in males, and temperatures in the middle will produce a combination of genders. With crocodiles, the results are reversed – with males usually born at higher temperatures. The sex of snakes is determined by chromosomes, as it is with mammals and birds. Once hatched, most reptiles are independent and able to care for themselves. Babies look like miniature adults, though their colors may be different.

More than one fifth of all known reptile species are considered endangered or close to becoming extinct. This has been particularly pronounced for island reptile species, counting at least 28 island reptiles having disappeared so far. This pattern of extinction, commonly seen in the islands, is finding its way toward the mainland as well. This crisis is mainly due to human intervention causing fragmentation in the continental habitats, which results in island-like territories, isolating species among each other. Reptiles are especially threatened by non-native species that compete for resources or feed on them, and habitat loss.

The longest reptile is the reticulated python, measuring over 32 feet. The heaviest is the leatherback sea turtle, weighing over 1,900 pounds.

Leaf chameleons of Madagascar measure only an inch from nose to tail.

Green sea turtles are the fastest reptiles, reaching speeds of 22 mph.

The Aldabra tortoise lives the longest, to over 150 years.

Reptiles are capable of solving complex problems and remembering what they have learned. They share the same level of intelligence as birds and mammals. They change techniques when presented with new challenges and learn from other reptiles. They possess advanced social skills and flexible behavior – behavior that can be adapted to meet a particular situation. In captivity, they learn how to open hinged doors, open jar lids, have the ability to interpret and anticipate common activities such as feeding time and cage-cleaning time, and can even navigate mazes. In the wild they exhibit advanced social behavior including recognition of their family, pair bonding and loving care of their children. They exhibit social learning, play behavior and cooperation. Studies show they are capable of counting, advanced learning and problem solving. They are able to reverse course in addressing problems, unlearning incorrect approaches almost instantly. They have individual personalities.

Shingleback skinks are often monogamous. They court for months with the male strutting, licking and nudging the female affectionately before mating. The reptilian couple will mate every breeding season for as long as 20 years. When one dies, its surviving partner will stay beside the body for days, tenderly touching it.

Australian monitors plan ahead and arrange ambushes when pursuing fast-moving prey. Monitor lizards have been shown to count snails at feeding time and learn to use their forearms to help extract insects from logs.

Alligators gather together in large groups during the spring, usually one to three hours after sunrise, to sing and engage in “alligator dances” for courtship. Mothers defend their nests from predators. Shortly before hatching, baby alligators call their mother to the nest and begin vocalizing to synchronize the hatching of their siblings. Mother alligators gently assist with opening the eggs and carry the babies to a special pool called a nursery. Young alligators will stay close to their mother and form social groups. They follow her wherever she goes, hop on her head to bask and follow her around on land like little ducklings. When in distress they call out for her, bringing her to their aid. They stay with their protective mother for up to 2 years after being born.

Crocodiles are behaviorally complex creatures that live and work as members of a group. They can be incredibly tender and affectionate. They play together, exhibit complex social interactions and gaze recognition, use tools, pair-bond, practice monogamy, hunt together and have good memories. Expecting mothers guard their nests and protect their young until they are old enough to survive on their own, up to 3 years old. Babies are carried around in their mouths to protect them. Crocodiles have community nurseries where one mother watches over the hatchlings of many. Crocodiles have excellent communication skills, using body language and sounds, and even vibrate to make water ‘dance’, producing sounds that humans cannot hear. 

Wild turtles who are caught and later released will head in the direction of the nearest water source. Captive turtles recognize the sight of their food container and sound of food rattling in it.

Green iguanas share nesting areas with as many as hundreds of other iguanas and construct complex burrow systems that are continuously improved upon. Babies hatching from eggs look around and duck back into the egg while observing other babies to determine if it is safe to emerge. They get excited and jump up and down when they see other babies emerging. Siblings will stay together for months, rubbing against each other frequently and wagging their tails like dogs. They sleep together and groom each other and walk in a line with a chosen leader. They rub each others' heads before returning to their family's territory, watching for predators together and protecting each other.

The Coccinellidae are a family of small beetles, commonly known as ladybugs in North America and ladybirds in Britain, Ireland, the Commonwealth and some parts of the southern United States. Entomologists in the United States prefer the names ladybird beetles or lady beetles, as these insects are not true bugs.

Coccinellids are found worldwide, with over 5,000 known species. They are often yellow, orange, or scarlet with small black spots on their wing covers, with black legs, heads and antennae. Color patterns vary greatly, however. Depending on the species, they can have spots, stripes, or no markings at all. Many species are mostly, or entirely, black, dark gray, gray, or brown. Seven-spotted coccinellids are red or orange with three spots on each side and one in the middle; they have a black head with white patches on each side. Most coccinellids have oval, dome-shaped bodies with six short legs.

The four most common types of ladybugs are:

The round-shaped ladybugs, Seven-spotted ladybug, originally from Europe. They are round and have a dome-shape, and are bright red with seven spots of black on the back of their bright red wings.

The oval-shaped ladybug, Convergent ladybug, which is orange with different spot patterns of black. They are common in the pacific coastal states.

The Multicolored Asian ladybeetle, a larger ladybug with five black spots and curved lines in the shape of the letter M. These ladybugs are originally from Asia and are now plentiful in the United States.

The C-Mac ladybug, an oblong pink and black spotted ladybug.

Ladybugs are generally considered useful insects, because many species feed on aphids or scale insects which are pests in gardens, agricultural fields, orchards and similar places. Within the colonies of such plant-eating pests, they will lay hundreds of eggs. When these hatch the larvae will commence feeding immediately. However, some species do have unwelcome effects; among these the most prominent are the subfamily Epilachninae, which are plant eaters. Usually, Epilachninae are only mild agricultural pests, eating the leaves of grain, potatoes, beans, and various other crops. But their numbers can increase explosively in years when their natural enemies, such as parasitoid wasps that attack their eggs, are few. In such situations, they can do major crop damage. They occur in practically all the major crop-producing regions of temperate and tropical countries.

Coccinellids are best known as predators of aphids and scale insects, but the range of prey species that various ladybugs attack is much wider. Some specialize in mites, some attack caterpillars and other beetle larvae. Others feed on various insects or their eggs. Larvae and eggs of ladybirds, either their own or of other species, can also be important food resources when alternative prey are scarce. Certain species of coccinellids are thought to lay extra infertile eggs with the fertile eggs, apparently to provide a backup food source for the larvae when they hatch. The ratio of infertile to fertile eggs increases with scarcity of food at the time of egg laying. Ladybugs are also now known to be far more omnivorous than previously thought. Their diets often include honeydew, pollen, plant sap, nectar, and various fungi. Some species are strictly herbivores.

The main predators of ladybugs are usually birds, but they are also the prey of frogs, wasps, spiders, and dragonflies. The bright colors of many ladybugs discourage some potential predators from making a meal of them. Their coloring is a reminder to any animals that have tried to eat their kind before that they taste awful. The blood of a ladybug is yellow and has a very strong smell that also acts as a repellent to predators. Ladybugs also play dead until predators pass.

Ladybugs in temperate regions enter diapause (a period of suspended development) during the winter, so they often are among the first insects to appear in the spring. Some species gather into groups and move to higher elevations, such as a mountain, to enter diapause. Most coccinellids overwinter as adults, aggregating on the south sides of large objects such as trees or houses during the winter months, dispersing in response to increasing day length in the spring.

Ladybugs go through a complete metamorphosis with egg, larval, pupal, and adult stages. Ladybug eggs look like small clusters of orange footballs. Female ladybugs can lay more than 2,000 eggs in one year. The eggs hatch in only a few days. Eggs are usually laid on leaves near an area where the larvae have easy access to food sources.

Baby ladybugs, larvae, look nothing like adults. They are long in shape and are generally one color, resembling small alligators. They are fast moving and they have big appetites. The larvae will eat aphids and other bugs for about 2 to 3 weeks. After they have grown to full size, they attach themselves to a plant leaf or a stem by their tail and begin a metamorphosis. Their skin splits down its back and exposes the pupa, which is about the same size and color as adults but with a protective layer until they develop wings. They pupate and turn into an adult ladybug within 7 to 10 days.

Ladybugs usually do most of their flying in the warmest part of the afternoon. They beat their wings 85 times per second. Their wings are made from chitlin, the same material human fingernails are made from.

As ladybugs grow older, their spots fade. Most ladybugs live for about a year, but some species can live up to three years. In a year they eat over 5,000 bugs, playing a vital role in the management of pests.

Due to habitat loss and changes in climate, ladybugs are threatened with extinction. Ladybugs are particularly sensitive to temperature changes, and will die from dehydration if they become overheated. Like most animals, the primary threat to ladybugs is the destruction of their habitat. Human development has taken an alarming toll on the environment. Impact from land use practices such as agricultural conversion, deforestation, and urban sprawl continue to degrade and fragment remaining pockets of habitat and accelerate biodiversity loss. Pesticides and other forms of pollution are also of serious concern, as well as genetically modified organisms (GMOs).

Although eels look like snakes, they are fish and belong to the order Anguilliformes, of which there are about 800 species. The term "eel" is also used for some other similarly shaped fish, such as electric eels and spiny eels, but these are not members of the Anguilliformes order.

The main species of true eels include American eels, European eels, moray eels and conger eels. Most eels are predators and feed on fish, snails, frogs, octopuses, crabs, lobsters and mussels. Eels feed during the night and rest during the day. These aquatic creatures rely on their excellent sense of smell to hunt for prey.

Eels are elongated fish, ranging in length from 2 inches in the one-jawed eel, to 13 feet in the slender giant moray. Adults range in weight from 1.1 oz to well over 55 lb. The heaviest true eel is the European conger. The maximum size of this species has been reported as reaching a length of 10 feet and a weight of 240 lb. Other eels are longer, but do not weigh as much.

Eels possess no pelvic fins, and many species also lack pectoral fins. The dorsal and anal fins are fused with the caudal fin, forming a single ribbon running along much of the length of the animal. Many eels have scales beneath their thick skin.

Most eels live in the shallow waters of the ocean and burrow into sand, mud, or amongst rocks. A majority of eel species are nocturnal, thus are rarely seen. Sometimes they are seen living together in holes, or "eel pits". Some species of eels also live in deeper water on the continental shelves and over the slopes as deep as 13,000 feet. Only members of the Anguilla regularly inhabit fresh water, but they, too, return to the sea to breed.

Some eel species travel up to 4,000 miles to breed. The journey can take over seven months to complete, during which time the eels do not eat. During mating, eels open their mouths wide and wrap their bodies around each other for hours. They separate only after the female has laid her eggs, which are then fertilized by the male. After the eels breed, they die. It takes three years for an eel to become an adult.

Baby eels begin life as flat and transparent larvae, or leptocephali. Eel larvae drift in the surface waters of the sea, feeding on marine snow, small particles that float in the water. Eel larvae then metamorphose into glass eels and then become elvers before finally seeking out their juvenile and adult habitats. Freshwater elvers travel upstream and are forced to climb up obstructions, such as weirs, dam walls, and natural waterfalls.

Eels can reverse metamorphosis. As temperatures cool and eels make their way downriver in their migration to spawn in the ocean, they undergo physical changes to prepare their bodies for spawning and for the transition from freshwater to the marine environment. One of these changes is gut degeneration as the eels cease feeding and rely on fat stores to make the lengthy journey back to the sea where they spawn and die. Eels that are delayed, for example due to barriers or rises in temperature, and are unable to complete their downriver migration can actually reverse that physical change and regenerate their guts.

Eels move through water with an undulating motion. Eels can swim backwards and forwards, and can travel on land for short distances.

Pollution, changes in the environment, over-fishing, drainage and hydro development are the main threats to eels. Eels lose habitat and migration corridors when waters are obstructed by dams and other mechanisms. Because many eels are catadromous (living in fresh water but spawning in the sea), dams and other river obstructions can block their ability to reach inland feeding grounds. Since the 1970s, an increasing number of eel ladders have been constructed in North America and Europe to help the fish bypass obstructions.

Localized population declines are also attributed to mortality in hydropower plant turbines, degradation of current habitat, and overharvest. Freshwater eels and marine eels are threatened by the seafood industry, with some eel populations decreased as much as 99%.

European eel populations are threatened by a foreign parasite from East Asia which appeared in European eels in the early 1980s. Since 1995, it also appeared in the United States (Texas and South Carolina), most likely due to uncontrolled aquaculture eel shipments. In Europe, eel populations are already from 30% to 100% infected with the nematode. The parasite inhibits the function of the swimbladder as a hydrostatic organ. As an open ocean voyager, eels need the carrying capacity of the swimbladder (which makes up 3–6% of the eel's bodyweight) to cross the ocean on stored energy alone.

Eels, particularly the moray eel, are also victims of the pet trade and animal entertainment industry. Captured from their native habitat and transported to various countries to be sold as aquarium "ornamentals", the dangers, difficulties, physical and physiological needs of the animals appears to be of no concern in the lucrative pet trade and animal entertainment industry. Removed from their natural habitat they are deprived of the ability to freely engage in instinctual behaviors. Even under the best of circumstances, captivity is cruel for fish. Confined to tiny tanks, captive fish endure constant stress and boredom. With little room to exercise, they become listless, their immune systems are weakened, and they become prone to sickness; many resort to self-mutilation in reaction to stress or boredom. Mental illness is rampant among confined animals.

Centipedes are arthropods belonging to the class Chilopoda of the subphylum Myriapoda. They are elongated creatures with series of body segments, with one pair of legs per body segment.

Despite the name, centipedes can have a varying number of legs from under 20 to over 300. Centipedes have an odd number of pairs of legs, therefore there is no centipede with exactly 100 legs. They have a pair of venom claws and are a predominantly carnivorous.

Centipedes normally have a drab coloration combining shades of brown and red. Cave-dwelling and subterranean species may lack pigmentation and many tropical species have bright colors. Size can range from a few millimeters to about 12 inches.

Worldwide, there are estimated to be 8,000 species of centipede. Centipedes have a wide geographical range, reaching beyond the Arctic Circle. Centipedes are found in an array of terrestrial habitats from tropical rainforests to deserts. Within these habitats, centipedes require a moist micro-habitat because they lose water rapidly through their skin. Accordingly, they are found in soil and leaf litter, under stones and dead wood, and inside logs. Centipedes are among the largest terrestrial invertebrate predators.

Centipede reproduction does not involve copulation. Males deposit a sperm capsule for the female to take up. In some species, the male undertakes a courtship dance to encourage the female to engulf his sperm. In other cases, the males just leave them for the females to find. In temperate areas egg laying occurs in spring and summer but in subtropical and tropical areas there appears to be little seasonality to centipede breeding.

Some centipedes lay their eggs singly in holes in the soil; the female fills the holes with soil and leaves them. The number of eggs laid ranges from about 10 to 50. Time of development of the embryo to hatching is highly variable and may take from one to a few months. Development to adulthood is also highly variable within and among species. For example, it can take 3 years for S. coleoptera to achieve adulthood, whereas under the right conditions Lithiobiomorph species may reach a reproductive period in 1 year. In addition, centipedes are relatively long-lived when compared to their insect cousins – some living up to 6 years.

Some centipedes provide parental care to their babies. The mother stays with the eggs, guarding and licking them to protect them from fungi. Some mothers stay with their young after they have hatched, guarding them until they are ready to leave. If disturbed, the female will either abandon the eggs or eat them; abandoned eggs tend to fall prey to fungi rapidly. Some species are matriphagic, meaning that the offspring eat their mother.

Centipedes are predominantly predatory animals. They are generalist predators, which means that they have adapted to eat a variety of different available prey. Centipedes are mostly nocturnal. What centipedes actually eat is not well known because of their cryptic lifestyle and thorough mastication of food. Centipedes are eaten by a great many vertebrates and invertebrates, such as mongooses, mice, salamanders, beetles and snakes. They form an important item of diet for many species. Centipede defenses include their speed and venomous forcipules, as well as the secretion of defensive chemicals.

Like most animals, the primary threat to centipedes is the destruction of their habitat. Human development has taken an alarming toll on the environment. Impact from land use practices such as agricultural conversion, deforestation, and urban sprawl continue to degrade and fragment remaining pockets of habitat and accelerate biodiversity loss.

Pesticides and other forms of pollution are also of serious concern, as well as genetically modified organisms (GMOs).

Lynx is a member of the cat family. There are four species of lynx within the Lynx genus: Spanish, Canadian, Eurasian lynx and the bobcat.

These medium-sized wild cats have short tails, tufts of black hair on the tips of their ears, large whiskers and a ruff under their necks with black bars resembling a bow tie. Their padded paws are large, allowing them to easily walk on snow.

The bobcat and the Canada lynx are the smallest species; the Eurasian lynx is the largest species; while each species may vary considerably.

Lynx coloring varies according their climate; from gold to beige-white to medium brown. Some have dark brown spots, especially on their legs. All lynx have white chests and bellies. The white fur extends to the insides of their legs. Lynx in the Southwestern United States are dark in color. In colder climates they are lighter in color.

The length of their fur and paw sizes also vary due to their climate. They are short-haired with smaller, less padded paws in the Southwestern United States. In colder northern climates, lynx have thicker, lighter colored fur and larger paws.

The Eurasian lynx lives in central and northern Europe across Asia up to Northern Pakistan and India. In Iran, they live in the Mount Damavand area. In North America, the Canada lynx and bobcat live in the temperate zone. Bobcats are common in the continental United States, southern Canada and northern Mexico. Canada lynx live in boreal forests of Alaska and Canada.

Lynx are usually solitary animals, though they sometimes travel and hunt together. Mating occurs once a year in late winter. A female gives birth to one to four kittens following a gestation period of around 70 days. Young lynx will live with their mother for another winter, or about nine months.

As young adults they live on their own, creating dens under ledges or in crevices. They prefer to occupy high altitude forests with dense grass, shrubs or reeds. They can climb trees and are proficient swimmers.

Their large paws help them to balance and hunt and to travel and hunt in snowy, high altitude habitats. Their acute hearing allows them to hear oncoming prey and predators over long distances. Sharp vision is another important sense used for hunting. Strong jaws and sharp teeth help the lynx to bite down on prey.

Lynx hunt from an ambush, using the element of surprise. These agile climbers spend most of their time in tree branches, waiting for prey to pass beneath them. Lynx eat a wide range of animals including snowshoe hares, fish, foxes, white-tailed deer, small red deer, chamois, squirrels, mice, birds, goats, sheep, voles, grouse, reindeer, roe deer and ptarmigans.

Lynx do not usually take their kill back to their den, except when a mother is providing food for her lynx kittens. They have very large ranges; the largest range of all felids. Male territories are larger and often overlap several female territories.

Lynx are very vocal cats. They meow, purr, hiss, chatter and yowl.

Lynx are nocturnal (active during the night). They are very cautious around people and predators. The main predators of lynx are cougars, coyotes, wolves, and humans.

Lynx can live over 14 years in the wild.

In many countries, the hunting of lynx is illegal. Bobcat hunting and trade is common the United States, though they are classified as a state endangered species in Ohio, New Jersey, Indiana, and Iowa - and as a State threatened species in Illinois. Regulated hunting is permitted in Mexico and in Canada.

Lynx populations have been greatly reduced due to hunting and poaching by the fur industry.

The Iberian lynx is almost extinct. They are currently being captive bred to be reintroduced to the wild. Reintroduction projects have also taken place in Europe, and resettlement attempts have been attempted in the United States.

The Spanish lynx is one of the most endangered cats in the world.

The Canadian lynx is becoming very rare in the northern United States due to hunting, habitat destruction and competition with bobcats.

Beetles are a group of insects which are biologically classified in the order Coleoptera. The word "coleoptera" is from the Greek, koleos, meaning "sheath"; and pteron, meaning "wing", thus "sheathed wing". Most beetles have two pairs of wings, the front pair being hardened and thickened into a shell-like protection for the rear pair and the beetle's abdomen.

There are more beetles on the planet than other other animal. Almost 25% of all known types of animal life-forms are beetles. About 40% of all insect species are beetles (about 400,000 species), and new species are discovered frequently. Some estimates put the total number of beetle species at as high as 100 million. Weevils, or snout beetles, and rove beetles are the most common.

The diversity of beetles is very wide. They are found in all major habitats, except the polar regions. Beetles live in freshwater and marine habitats and everywhere vegetative foliage is found - from trees and their bark to flowers, leaves, and underground near roots. They even live inside plants, in every plant tissue, including dead or decaying ones.

Particular species of beetles are adapted to practically every kind of diet. Some break down animal and plant debris; some feed on particular kinds of carrion such as flesh or hide; some feed on wastes such as dung; some feed on fungi; some on particular species of plants and others on a wide range of plants. Some beetles are pollen, flower and fruit eaters and help to pollinate flowers. Others are predatory, usually on other invertebrates; some are parasites or parasitoids. Many of the predatory species are important controls of agricultural pests that damage crops. Conversely, beetles are prey of various invertebrates and vertebrates, including other insects, fish, reptiles, birds, and mammals.

Beetles have a hard exoskeleton, particularly on their forewings, distinguishing them from most other insect species. Like all armored insects, beetles' exoskeletons comprise numerous plates, some fused and some separated by thin sutures. This combines armored defenses with flexibility. All insects' bodies are divided into three sections: the head, the thorax, and the abdomen.

Beetles are endopterygotes; they undergo complete metamorphosis, a biological process by which an animal physically develops after a birth or hatching, undergoing a series of changes in its body structure. The typical form of metamorphosis in beetles passes through four main stages: the egg, the larva, the pupa, and the imago or adult.

Beetles may display extremely intricate behavior when mating. Pheromone communication is likely to be important in the location of a mate. Another way species of Coleoptera find mates is the use of biosynthesized light, or bioluminescence. This special form of a mating call is used by fireflies by the use of abdominal light-producing organs. The males and females engage in complex dialogue before mating, identifying different species by differences in duration, flight patterns, composition, and intensity.

Before mating, males and females may stridulate, or vibrate the objects they are on. In some species, the male climbs onto the female and strokes her with his antennae. Conflict can play a part in the mating rituals of some beetles. Many male beetles are territorial and will fiercely defend their small patches of territory from intruding males. In such species, the males may have horns, making their overall body lengths greater than those of the females, unlike most insects. Pairing is generally quick, but in some cases will last for several hours. During pairing, sperm cells are transferred to the female to fertilize the egg. A single female may lay from several dozen to several thousand eggs during her lifetime. Parental preparation varies between species, ranging from the simple laying of eggs under a leaf to constructing underground structures complete with a supply of dung to house and feed their young. Other beetles are leaf rollers, biting sections of leaves to cause them to curl inwards, then laying their eggs, thus protected, inside. Some beetles will patrol the eggs and larvae and apply a burrowing behavior to keep them from flooding and from asphyxiating. The mother will protect the eggs and larvae from predators.

The larva is usually the principal feeding stage of the beetle lifecycle. Larvae tend to feed voraciously once they emerge from their eggs. Some feed externally on plants, while others feed within their food sources. The larvae of many beetle families are predatory like the adults. The larval period varies between species, but can be as long as several years. Like adult beetles, the larvae are varied in appearance, particularly between beetle families.

All beetle larvae go through several instars, which are the developmental stages between each moult. In many species, the larvae simply increase in size with each instar as more food is consumed. In some cases, however, more dramatic changes occur. Among certain beetle families, particularly parasitic beetles, the first instar is highly mobile and searches for a host, while the following instars are more sedentary and remain on or within their host. Beetle larvae pupate, and from these pupae emerge fully formed, sexually mature adult beetles. Adults have extremely variable lifespans, from weeks to years, depending on the species.

Beetles have a variety of ways to communicate, some of which include a sophisticated chemical language through the use of pheromones. Some beetles stridulate to communicate, rubbing body parts together to create sound. They have a "scraper" on their abdomens that they rub against a grooved surface on the underside of their left wing cover to create a sound that is not audible to humans. Female beetles will stridulate and produce pheromones to attract other unmated males and females. New females arrive and do the same. As the males arrive, they enter the galleries that the females have tunneled, and begin to stridulate to let the females know they have arrived, and to also warn others that the female in that gallery is taken. At this point, the female produces a different pheromone to deter more beetles from coming.

Since species of beetles use environmental stimuli to communicate, they are affected by the climate. Microclimates, such as wind or temperature, can disturb the use of pheromones; wind would blow the pheromones while they travel through the air. Stridulating can be interrupted when the stimulus is vibrated by something else.

Like most animals, the primary threat to beetles is the destruction of their habitat. Human development has taken an alarming toll on the environment. Impact from land use practices such as agricultural conversion, deforestation, and urban sprawl continue to degrade and fragment remaining pockets of habitat and accelerate biodiversity loss. Pesticides and other forms of pollution are also of serious concern, as well as genetically modified organisms (GMOs).

Poison dart frogs are one of the most poisonous species on Earth. They are also among the most brilliant and beautifully colored animals on the planet.

Poison dart frogs are native to the tropical jungles of South and Central America, and a few species inhabit the Hawaiian Islands. The brightly colored bodies of poison dart frogs warn potential predators that eating them can be deadly. The vibrant colors of different species of poison dart frogs include gold, yellow, copper, red, blue, green and black.

There are around 200 different poison dart frog species inhabiting jungles across Central and South America. Poison dart frogs vary in colors, size and the toxin levels that they excrete from their skins depending on their species and habitat.

Poison dart frogs, also called poison arrow frogs, get their name from the fact that indigenous peoples have used poison dart frog toxins on the tips of arrows and blow-darts.

Poison dart frogs live on the ground under leaves, logs and rocks, or in foliage just above the ground. They inhabit moist and humid forests that have low levels of pollution.

Poison dart frogs are carnivorous; they feed purely on meat. They use their long, sticky tongues to catch invertebrates, especially certain ants, termites and beetles that may build up poisons in the frogs.

Poison dart frogs are diurnal (active during the day), unlike most tropical frogs which are nocturnal (active at night).

Poison dart frogs communicate with a wide variety of sounds to attract mates, declare territories and express distress. Most male poison dart frogs have vocal sacs that work as resonating chambers. Different species of poison dart frogs have different languages.

Poison dart frogs breed throughout the year, as long as there is sufficient rainfall. They engage in elaborate courtship rituals. The male poison dart frog leads a female to a specially chosen site to lay the eggs. Often several sites are visited before one is chosen. Courtship can last several hours and involves a mating dance of mutual stroking and cleaning of the leaves. The female poison dart frog then deposits her eggs into dark, moist leaf litter. Males fertilize the eggs. Both males and females guard the eggs and watch to make sure they don't dry out.

Many poison dart frogs are devoted parents. They carry both eggs and babies on their backs. Some poison dart frogs carry eggs from the ground to the safety of the tree canopy. The eggs stick to mucus on the mother's back while she transports them to a water-pool in a flower high up in the trees. The mother poison dart frog continuously lays unfertilized eggs in the water for her newborn babies to eat. Male poison dart frogs can be exceptional parents, attending to the babies, sometimes exclusively, and also performing transportation duties. Baby poison dart frogs, called tadpoles, eat a variety of foods from algae and detritus, to dead insects and insect larvae. After several months, tadpoles go through metamorphosis and transform into frogs.

Since poison dart frogs are toxic, they have few natural predators in the wild. Many animals become extremely sick just from licking a poison dart frog. One species of snake is immune to the poison of the poison dart frog.

Poison dart frogs can live over 10 years in the wild.

THREATS TO POISON DART FROGS

Many poison dart frog species are facing a rapid decline in populations Some species of poison dart frog have been classified as endangered due to loss of habitat, pollution, pesticides, the pet trade and disease. Being sensitive to pollution endangers poison dart frogs. Chemicals used in animal agriculture are retarding the growth of poison dart frogs and disrupting their reproductive cycles.

Poison dart frogs are alarmingly threatened by the illicit pet trade. Though protected by law, they are smuggled illegally then condemned to an unnatural life in a small aquarium for human amusement. 90 percent of exported poison dart frogs die in transport. The pet trade is also responsible for the spread of a fungus that has decimated poison dart frogs – the greatest disease-caused loss of biodiversity, both plant and animal, in recorded history.

Majestic, beautiful and graceful, swans are large aquatic birds closely related to geese and ducks. Swans inhabit both sides of the Equator across the Northern and Southern Hemispheres. There are several species of swan, differing in size, color and behavior: the Black swan, Mute swan, Black-necked swan, Trumpeter swan, Tundra swan (which includes the Bewick’s swan and Whistling swan), and the Whooper swan.

Northern swans are white with orange beaks. Southern swans are white and black with orange, red or black beaks. The legs of swans are usually a dark blackish gray color, except for two South American species that have pink legs. Black swans are known for swimming with one leg – tucking the other above their tails to change direction more smoothly and quickly when they spot predators or prey.

Swans have streamlined bodies, long necks and webbed feet. Their wings are very strong, making them able to fly short distances despite being such heavy birds. Their incredibly strong wings can cause fatal injuries to other animals.

A male swan is called a cob, a female swan is a pen, and a baby swan is a cygnet.

Swans are omnivores, but eat a mostly vegetarian diet. Swans eat aquatic plants, seeds, insects and sometimes small fish. Swans do not have teeth, but their beaks have serrated edges that look like teeth and aid in catching and eating food. When threatened, swans engage in busking - rearing up with flared wings and hissing, snorting, grunting and flapping.

Some species of swan are migratory, either wholly or partly.

Swan couples establish strong bonds. Some mate for life. Swans often touch beaks to kiss. When they kiss, their necks form a heart.

Swans can sleep on land or in the water. When sleeping on land they stand on one leg.

Swans molt each summer. When molting they are unable to fly for about 6 weeks. Breeding couples do not molt at the same time as they, and their babies, would be too vulnerable to predators.

During mating season, courtship dances are accompanied by a variety of hissing and grunting sounds. Some swans sing and honk during mating, and engage in synchronized swimming and head bobbing.

Swan couples build their nests on land with twigs and leaves. Unlike most ducks and geese, male swans help with nest construction and egg incubation. Female swans lay 3 to 9 eggs. Baby swans hatch following an incubation period of a little over a month. Baby swans are usually swimming in the water with their mother in a couple of days. They stay close to their mother for warmth and protection. Swans are known to aggressively protect their nests and babies.

Due to their large size, swans have few natural predators. Natural predators include wolves, foxes and raccoons that prey on swans and their eggs.

Swans can live 30 years in the wild.

Swans are a threatened species due to hunting, habitat loss and pollution. Some species are endangered. Swan populations are declining.

Swans are also victims of the animal entertainment and pet industries – used as decorations in ponds and lakes.

While sponges may look plant-like, they are multi-cellular animals that have bodies full of pores and channels allowing water to circulate through them. Sponges are bottom-dwelling sea creatures. They do not have nervous, digestive or circulatory systems. Instead, they obtain nourishment and oxygen from water constantly flowing through them. The flowing water also carries out waste products.

There are many different types of sponges in the world's oceans. Sponges come in two basic types: encrusting or free-standing. Encrusting sponges typically cover the surface of a rock in the same manner that moss covers a rock on land. Free-standing sponges have more inner volume compared with their outside surface area and sometimes grow into strange shapes, often reaching gigantic proportions.

All sponges are sessile (they are not able to move about) and aquatic animals. Although there are freshwater species, the great majority are marine (salt water) species, ranging from tidal zones to depths exceeding 5.5 miles. Most sponges live their lives attached to a reef.

Sponges are similar to other animals in some ways, but unlike most animals they lack true tissues and organs and have no body symmetry. The scientific term for sponges is Porifera which literally means "pore-bearing." They are covered with tiny pores which lead to a system of canals and out to one or more larger holes. Within the canals of the sponge, chambers are lined with specialized cells that have a sticky, funnel shaped collar and a hairlike whip. The collar cells force water through the sponge. The water brings in nutrients and oxygen, while it carries out waste and carbon dioxide. The sticky collars of the collar cells also pick up tiny bits of food brought in with the water. Another type of cell takes the food to other cells within the sponge.

Sponges are very effective filter feeders, since they are able to capture and eat particles as small as bacteria as well as much larger particles. The "skeleton" of the sponge is composed of tiny needle-like splinters called spicules, a mesh of protein called spongin, or a combination of both.

Most sponges are hermaphroditic (both male and female), but play either the male or female role during reproduction. Sperm is released into the water by "male" sponges and travels to "female" sponges, where fertilization occurs internally. Baby sponges are released from the female sponge and float around in the water column as plankton for a few days. They then settle down and start growing. The next time the sponges reproduce, they may change sexual roles.

Sponges are also known for regenerating from fragments that are broken off, although this only works if the fragments include the right types of cells. A few species reproduce by budding. Budding is a form of asexual reproduction in which a new organism develops from an outgrowth, or bud, due to cell division at one particular site. Since the reproduction is asexual, the newly created organism is a clone and is genetically identical to the parent organism. Some species of sponge produce "survival pods" that remain dormant until conditions are right, and then either form completely new sponges or recolonize the skeletons of their parents.

While most of the approximately 5,000–10,000 known species feed on bacteria and other food particles in the water, some host micro-organisms as endosymbionts (organisms that live within the body or cells of another organism). These alliances often produce more food and oxygen than they consume. A few species of sponge that live in food-poor environments have become carnivores that prey mainly on small crustaceans.

Sponges are susceptible to damage by fishing, especially bottom trawling and dredging. In typical trawling, a large net is dragged across the ocean floor, its mouth held open by two 2-ton doors called otterboards. The siliceous skeleton of the sponges is fragile, and these organisms are easily broken by physical impact. Sponges in the vicinity of trawl tracks are shattered or completely removed.

While less harmful, hook and line fishing, as well as crustacean trapping, may also damage sponges. When the fishing gear is hauled to the surface, the lines and traps drag along the ocean floor and have the potential to break corals and sponges. Breakage of reef sponges may have dire consequences for the recruitment of new sponges, as sponge larvae require the siliceous skeletons of past generations as a substrate. Without a hard substrate, new sponges cannot settle and regrow broken parts of the reef. It has been estimated that broken sponge reefs may take up to 200 years to recover.

In addition, offshore oil and gas exploration threatens sponge reefs. Even if exploratory drilling is not done on or immediately adjacent to the reefs, it may still have a negative impact by increasing the amount of sediment in the seawater, or through hydrocarbon pollution.