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Narwhals: The Tusked Divers Of The Deep

Yellow Magpie — Sat, 24 Dec 2011 15:01:10 +0000

A helical sword pierces the skin of water, slashing it then slipping through before going deep under. It rises again, this time its holder breaches the surface. This mysterious toothed fencer belongs in another time, in the land of make-believe, myths and fantasy but it is here, it is real.

The Narwhal has to be one of the most bizarre of all the creatures to have lived on Earth. Fortunately for us, it is still alive, still amongst us.

A member of the toothed whales, or Odontocetes group, Narwhals possess perhaps the most remarkable tooth in the entire animal world. Growing two and a half metres (nine feet) in length males have an enormous left tooth protruding through their mouths.

When one looks at a male Narwhal it is very hard to get beyond their tooth and notice the rest of their body. In comparison to other whales, Narwhals are quite small. They are found exclusively in the frigid waters of the Arctic Ocean.

The Strangest Of Appearances

The narwhal, named after the Norse word for corpse, is closely related to the Beluga Whale. Both the Narwhal and the Beluga whales are very similar in appearance, save the wrought tusk. They have short snouts and the two species are sometimes considered white in appearance. The Narwhal is a mixture of black and white in comparison to the relatively all-white, Beluga.

At birth Narwhal calves are much darker in appearance. As they grow older they become whiter in colour.

However, by far the most eye-catching feature of the Narwhal is its tremendously impressive tusk. The males possess the larger tusk which is an enormous tooth that protrudes up to three metres (ten feet). Interestingly, the tusk, which can weigh ten kilograms (22 lbs), is nearly always the left tooth.

On rare occasions, males have two tusks jutting out from the upper jaw. There is also one recorded account of a female with two tusks, something which is thought to be very rare indeed.

No one is exactly sure why Narwhals have such strange tusks. The general consensus is that it is probably related to sexual selection. Males with larger tusks are thought to be perceived by females as more dominant and therefore more desirable to mate with.

According to Wikipedia, this hypothesis is further strengthened by the fact that Narwhals have very rarely been seen using their tusks for fighting, or breaking through sea ice – which are other ideas that have also been put forward as an explanation.

Diet And Diving

Narwhals feed on cod, shrimp, squid and halibut. They have very different feeding habits depending upon the seaon. In winter they hunt for food in deep waters while in summer they prefer relatively shallow water. Somewhat unusually they obtain the most energy from food during the winter period rather than during the summer.

What separates Narwhals from nearly every other mammal is their deep diving. During the winters they can reach depths of over 1,500 metres (5,000 feet). They have been observed diving over 15 times per day. Each dive typically lasts 25 minutes.

Narwhals’ Future

Currently, the population of Narwhals is thought to be very healthy. Their only predators, besides subsistence Inuit hunters, are killer whales and polar bears. Climate change however does pose a significant threat. Luckily, at least for now, we still have these magnificent animals, more akin to mythical creatures, with us.

Vital Statistics

Narwals are up to five metres (16 feet) in length.
The larger males can weigh up to 1,600 kilograms (3,500 lbs) with the females coming in around 1,000 kilograms (2,200 lbs).
Narwals are found in the cold Arctic waters off Canada and Greenland.
They are thought to live to be up 90 years old.

http://www.youtube.com/watch?v=44sjE_x1X4k

Blue Whale: The World’s True Giant

Yellow Magpie — Thu, 03 Nov 2011 23:51:32 +0000

There is no getting away from the enormity of the blue whale. Its behemoth mass plays tricks on you. In fact, you could be easily forgiven for thinking that something this gigantic, this monstrous couldn’t surely be alive?

But it is alive and not alone that, its sleek aerodynamic shape means its incredibly mobile too. Despite weighing more than 25 times the weight of an adult male African Elephant, the Blue Whale could leave the elephant standing flat-footed in its wake, such is its pace.

King Of The Rorquals

The Blue Whale is part of the Rorqual group of baleen whales which also contains the Fin Whale. Rorquals are giants of the sea. They have distinguishing folds running along the underside of their body from the lower jaw to the navel.

These longitudinal sections expand when the whale is feeding allowing it hold mammoth quantities of water and food.

Big Feeders

As you would expect, as the largest known animal that has ever lived, the appetites of Blue Whales are voracious. When their prey is most plentiful they can eat up to two per cent of their own body weight – 4,000kg (8,800lbs).
Although Blue Whales are still mysterious creatures, scientists believe that they spend eight months of the year feeding, sometimes they can eat continuously for hours at a time.

The preferred food of the Blue Whale is krill which they feed on almost solely. Their feeding method is identical to the Fin Whale. After diving down to the required depth they lunge at their prey opening their massive jaws right and quickly hoovering up their prey. They filter out the water and lick off the food from the baleen hairs.

Record Setter

As the largest known creature that ever lived, the Blue Whale holds many records. It has the largest heart of any animal at 600 kilogrammes (1,300 lbs) with an aorta over 20 centimetres in diameter (eight inches). It can pump ten tonnes of blood around nearly two million kilometres (one million miles) of blood vessels.

Unlike the heart of a human, which pumps on average at 72 times per minute, the heart of a Blue Whale just beats five to six times per minute transporting huge quantities of blood throughout its body.

It also has the largest tongue of any animal weighing in at just under 3,000 kilogrammes (6,000 lbs). It’s cavernous mouth can hold a total of over 90,000 kilogrammes of water (198,000 lbs) or put another way, over 100 people of average size could fit inside with room to spare. With a capacity of 5,000 litres, the Blue Whales lungs are once more the biggest to be found in any animal.

Lone Sprinters

Blue Whales can zip through the water at speeds reaching 50 kilometres per hour (31 miles per hour) over short distances. They can cruise for long periods at speeds of 20 kilometres per hour (12 miles). However, when they are feeding they slow right down to a walking pace of five kilometres per hour (three miles).

Unlike Fin Whales, which are social mammals, Blue whales either are solitary or live in pairs. This is atypical of most of the baleen whales who prefer to form large groups.

Booming Vocals

The voices of Blue Whales are the most powerful of any animal. With sounds ranging from between 150 and 188 decibels at a distance of one metre, they can project their voices for hundreds of kilometres. To give you some idea of just how loud this is, 190 decibels is the sound generated at blastoff by a rocket headed for Outer Space.

As of yet, we still do not know what these whales are communicating. However, scientists are optimistic that within the next five years we will have developed the technology to start to communicate with these mysterious creatures.

Threats To The Great Blues

The advent of faster boats and better harpoon technology meant that the Blue Whale was commercially hunted in huge numbers towards the end of the 19th century and during most of the 20th century.

By the time commercial hunting of the Blue Whale was outlawed in 1966 just under 400,000 animals were estimated to have been killed.

Orcas are now the Blue Whales’ only natural predator. Nevertheless, scientists believe that fatalities caused by Orcas are relatively rare events. Other threats that Blue Whales face are collisions with ships and entanglement in fishing nets.

However, a far more sinister dangers may lurk in the form of poly-chlorinate biphenyl (PCB) which is created in the manufacturing process of plastics. You can read Yellow Magpie’s The Polar Bear: An Indicator Of A Failing World? for further insight into the effects of PCB.

Vital Statistics

Blue whales have been measured to be over 33 metres (110 feet) in length.
They have been estimated to weigh up 190,000 kilogrammes (418,000 lbs)
Blue Whales are found throughout the world’s oceans and seas.
Scientists believe that these whales can live to be over 80 years old but they could conceivably live to be a lot older.

http://www.youtube.com/watch?v=K40D83obI8U

Fin Whale: The Giant Speedster Of The Oceans

Yellow Magpie — Wed, 02 Nov 2011 20:13:31 +0000

Onlookers on a boat witness a rare sight. A sleek object darkens the surface of the water from below. It moves rapidly and cuts through the liquid medium. It’s elongated snout cleaving the water apart. The object briefly surfaces and bellows out a plume of water. With a flick of its gigantic tail it submerges and disappears into the depths.

Fin whales dubbed the ‘greyhound of the seas’ really do live up to their billing.

Speeding Giants Of The Oceans

Fin whales are enormous, after the Blue Whale they are the largest living animal. At 90,000 kg (150,000lbs) and up to 25 metres (82 feet) in length, these creatures belong to a select group of baleen whales called Rorquals. Rorquals are giant baleen whales.

Not only are Fin whales large, their sleek-lined bodies propell them at high speeds through the world’s oceans. Sprinting at up to 40 kph hour (25 miles) these creatures are extremely fast. They can maintain speeds in excess of 35 kph (22 mph) for considerable periods of time.

Huge Creatures: Huge Appetites

Because of their vast bulk Fin Whales need to eat a lot of food to maintain their size and to keep alive.

Like all baleen whales, Fin Whales are filter-feeders. They use their plates of baleen which contains tens of thousands of long hairs to trap their prey. The water gets filtered out and the whale uses its tongue to swipe off the food, swallowing it down their throats.

Fin Whales feed on small animals such as krill, fish and squid.

According to a report from the University of British Columbia the whales power through the water while feeding at about 11 kilometres per hour (seven miles per hour). When eating they can plunge to the depths greater than 200 metres (600 feet).

Once they have targeted their prey the whales open their jaws and lunge after the small creatures. It is estimated that a single lunge can net the whales ten kilogrammes (22lbs) of food. An adult whale can consume over 1,500 kilogrammes (3,300 lbs) of food a day.

Remarkable Communicators

Fin Whales communicate with one another over vast distances. They repeat patterns and phrases after intervals and these sonorous displays can last for days at a time.

The sounds can be heard hundreds of miles away. They are able to travel such enormous distances because the sounds they make are incredibly loud and also because water is an excellent medium for the transmission of sound-waves.

At a distance of one metre Fin whales can emit low-pitched grunts that can exceed 185 decibels. To give you an idea of how loud that is a stun grenade only reaches 180 decibels from the same distance of one metre.

A Shaky Human Relationship

When people began commercial whaling back in the 19th century, whales such as the Fin Whale and Blue Whale were relatively safe as they were so fast. It wasn’t until the invention of more powerful harpoons, together with the exhaustion of other whale species, that the Fin whale became a target.

Throughout the 20th century nearly three quarter of a million Fin Whales were killed. 1987 was the year that finally saw the killing of Fin Whales outlawed. To date, only Iceland, Japan and subsistence hunters kill these animals which has allowed the Fin whale population to painstakingly recover although they still remain on the endangered list.

Nowadays the biggest concern for Fin whales is accidental collisions with ships. The noise-filled oceans are thought to play a significant role in confusing these animals causing the collisions.

Vital Statistics

Fin Whales can almost reach lengths of 27 metres (87 feet). Females are much larger than males.
They can weigh as much as 70,000 kilogrammes (150,000 lbs).
Fin Whales are found throughout the world’s oceans.
They can live to be an estimated 140 years.

http://www.youtube.com/watch?v=eGwTKlKeIMA

The Bowhead Whale: Long-Lived Giants Of The Artic

Yellow Magpie — Wed, 26 Oct 2011 20:42:57 +0000

A huge dark shape slowly moves underneath the surface of the frigid water. The mammoth mammal breaks the surface and takes in enormous amounts of air in a single breath. This extraordinary creature is unique among animals. The longest living mammal in the world it has seen sights that would astound.

Bowheads are considered to be a species of Right Whale. They are also the second most-massive of all the whales, only the Blue Whale is larger.

Huge Mouths And Thick Skulls

These whales have massive jaws and thick skulls. Their craniums allow them to pierce through substantial layers of ice, up to half a metre or more (two feet). Their colossal jaws allow the bowhead to have the largest mouth of any animal.

The freezing-cold environment of the Artic waters means that the Bowhead Whale has to have a consolidated layer of blubber to insulate itself from the chilly waters. Their blubber is thought to be the thickest of all the whales at up to half a metre (two feet) in thickness.

As baleen whales, Bowheads filter their prey through baleen plates (long hair-like structures), which at over three metres in length (ten feet), makes them the longest of all the whales.

The Impact Of Whaling

Whaling has had a devastating impact on the numbers of Bowheads. From an estimated figure of 50,000 before the advent of whaling, the population has now been reduced to half that number.

The fact that these whales swim very slowly, less than six knots, and float after death did not do them any favours. These characteristics are features of the Right Whales and are the reason why people preferred to hunt them.

Nowadays these whales endure a better relationship with people and are only killed by subsistence hunters such as the Inuit.

Long Lived

One of the most interesting aspects of Bowhead whales is their longevity. It is now believed that Bowheads can live up to 200 years or more. Scientists have based this on the fact that slate and ivory spear heads dating back to the 19th century were found in the 1990′s. This means that they are plenty of Bowhead whales that probably remember the days of 19th century hunting.

If we could communicate with these creatures imagine what they could tell us? Their lifespans, three-fold that of the average human, are astonishing. Thankfully, our relationship with these friendly giants has improved enormously from the days when they were commercially killed.

Vital Statistics

Bowhead Whales can be up to 20 metres in length (65 feet). Females are larger than their male counterparts.
They can weigh as much as 100 tonnes.
Bowhead Whales are thought to be the longest living of all mammals and scientists believe that they can be over 200 years old.
They are found throughout the artic.

http://www.youtube.com/watch?v=1IsW7t2e22g

The Right Whale: Friendly Creatures Of The Oceans

Yellow Magpie — Wed, 26 Oct 2011 20:36:08 +0000

A friendly, amicable giant closes in to investigate a group of people on a small fishing craft. The huge creature perches itself right against the boat allowing the occupants to rub its head in a mutual gesture of openness. All throughout the world these scenes are being repeated as Right Whales live up to their social billing.

The Story Of The Many Species

Rights whales are actually three separate species of whales lumped together. These three species are the North Atlantic Right Whale, the Southern Right Whale and the North Pacific Right Whale. The Bowhead whale is considered by some to be part of the Right Whale group however this whale is discussed separately in another post.

According to Wikipedia, genetic testing of the right whales suggest that the northern and southern species stopped interbreeding somewhere between 12 and three million years ago. In an interesting twist it has been recently discovered that the North Pacific Right Whale is more closely related to the Southern Right Whale and not the North Atlantic Right Whale as had been expected.

Right Whale, Wrong Characteristics

Unfortunately, the nomenclature of the Right whale has bad connotations. They were named this because they were friendly, swam close to shore, moved slowly (not more than six knots) and floated when killed. This made them the ideal or ‘right whale’ to hunt.

The Right Profile

Right Whales are very bulky in comparison to the sleek profiles of other whales. This is created by a huge amount of blubber which has been calculated to be 40 per cent, or more, of their total body weight. It is this huge amount of fat that makes these whales float.

The whales need such large amounts of blubber to keep their bodies insulated from cold waters. White lice are found in patches throughout their head resulting in callosities which are coarse areas of skin.

With testicles weighing up to one metric tonne (500 kilogrammes each) these animals have the largest gonads of any creature.

Right Whales are baleen whales and have baleen plates that can be over two metres in length (six feet). (Baleen is a system of hairs that some whales use for feeding.) They have between 200 and 300 of these baleen plates which filter their food.

Zooplankton Feeders

Right Whales feed almost exclusively on zooplankton such as krill. They use their baleen plates to filter out the water leaving the prey to be eaten.

Threats To Rights

There are only two predators to right whales, Orcas (Killer Whales) and people. Unfortunately for these whales, their natural behaviour and large amount of blubber meant that they were ideal for whaling. Despite the world-wide ban on the whaling of Right Whales in 1937 due to their decimation, illegal hunting continued and several thousand whales were killed.

Watching The Rights

Nowadays, hunting of these whales by people is been replaced by whale watching. The same behavioural characteristics that made them easy to hunt makes them the perfect subjects for whale watchers. Many countries now make substantial sums of money from Right Whale watching tourism. Brazil and South Africa are two of the leading exponents of this new type of commerce.

This new departure paves the way for better relations between people and our mammalian cousins.

Vital Statistics

Right Whales are up to 18 metres in length (60 feet).
They can weigh up to 92 metric tonnes (100 short tons).
It is believed that Right Whales can be 70 years old or more.
They are found in the North and South Atlantic, the Arctic and North Pacific.

http://www.youtube.com/watch?v=BiUkRYgGUW4

The Whales: Kings Of The Cetaceans

Yellow Magpie — Thu, 13 Oct 2011 21:44:38 +0000

They are the largest creatures to ever live on Earth. The biggest, weighs in excess of 180 tonnes, twice as heavy as the largest dinosaur. Perhaps what is most amazing is that these enormous creatures are still with us, still roaming the seas.

But there is much more to whales than just their size. And as we discover more and more about our mammalian cousins, it is becoming increasingly clear that these are highly intelligent creatures with a lot to teach us.

The Original Hippo?

Whales were originally land animals, most closely related to the hippopotamus. For whatever reason, the ancestors of whales decided to return into the sea. The proof of this is found in vestigial remains of hind limbs which are buried deep within the body of the whale. It is also worth noting that their stomachs are multi-chambered belying their ungulate origins.

Pakicetus is thought to be the ancestor of all whales. A small dog-sized hunting animal, pakicetus was very different from modern-day whales.

Originally whales would have had fur but gradually over time they developed blubber. Blubber is a much better insulator than fur and allowed the whales to dive into deeper water without the risk of hypothermia.

Toothed And Baleen Types

There are two kinds of whales. The toothed whales which include the Sperm whale, dolphins, including the Killer Whale and the extremely strange, Narwhal. The other variety is the baleen whale which are filter feeders. The Fin whale, Right Whale and Humpback whale are baleen cetaceans.

With the notable exception of the Sperm whale, toothed whales are generally a lot smaller than baleen whales. They use echolocation to hunt their food and have much larger brains than their baleen counterparts.

Baleen Whales

Baleen whales do not have teeth. Instead they have hairs which filter out the sea water and retain the fish. This hairy filter, or baleen, can be up to three metres (ten feet) in length and weigh up to 90 kilograms (200 lbs).

Baleen whales eat as much fish as possible while maximising their efficiency. They do this by swallowing as much as fish as their massive mouths allow.

Baleen whales, like the fin whale, have another trick up their sleeve which allows them to catch fish in massive quantities. This adaptation is found in their jaws. Their mouths open through dis-articulating jaws taking in as much food as feasible.

The whales hyoid bone is heavily involved in their vocalisation process. The larynx is incredibly elastic, ballooning out it forces air through.

Both baleen and toothed whales can be heard for hundreds of miles underwater.

Communication and Locomotion

Both dolphins and whales move very differently from fish. Whereas fish propel themselves with a side to side motion, whales and dolphins gain trust by moving their body along a vertical plane.

The hyoid is a critical bone for locomotion. According to comparative anatomist, Joy Reidenberg, the whale’s ability to move starts with its throat and the hyoid bone.

A Colossal Digestive System

The digestive system of whales are massive. The intestines of whales are thought to be five to six times the total length of their body. Therefore, a fin whale of 25 metres (80 feet) in length would have an intestinal tract of between 125 and 150 metres (400 and 500 feet).

Due to their aquatic environments, whale faeces contains a high amount of water in comparison to a land mammal. This helps it to get rid of waste more effectively.

Adapted For The Great Deep

The alien world of the aquatic is very different from the environment that we inhabit on a daily basis. Down in the deep waters of the Earth’s oceans, pressures are incredible, enough to crush all but the most specialised of creatures. To cope with overwhelming forces and the long duration of many of its dives, the whale has unusual adaptations.

The whales heart, which can weigh over one tonne, pumps at a very slow rate of two to three beats per minute when underwater. The lungs can take in over 2,000 litres in one breath.

With the huge pressures of the deep water sensory parts must be adapted. The eye of a whale is very strong and does not compress despite the huge forces. Whales ears, which are critical for both communication and echolocation are attached to their skulls and are not external like many land-based mammals.

A Difference Of Size

One thing that immediately strikes us about whales is their appearance. Whales have reached the size that they are because of the environment they live in. In a weightless world, whales are free to grow to massive sizes.

Vital Statistics

Whales can be as small as 2.5 metres in length (dwarf sperm whale) and as long as 30 metres (blue whale).
They can weigh as little as 250 kilogrammes (550 lbs) and as much as 180 tonnes.
Bowhead whales can live to be over 200 years.
Whales are found throughout our oceans.

http://www.youtube.com/watch?v=BiUkRYgGUW4

Highly Recommended

Inside Nature’s Giants is a well-shot Channel 4 documentary. From September 2011 a book will be available covering the animals shown in the series.

You can get Inside Nature’s Giants from here.

Amazon.co.uk
For people living in Ireland or the United Kingdom, you can access: Inside Nature’s Giants from here.

Amazon.ca
For those who live in Canada, you can obtain: Inside Natures Giants here.

Amazon.de
For Germany: Inside Nature’s Giants.

Amazon.fr
For France: Inside Nature’s Giants.

The Camel: The Adapted Ship Of The Desert

Yellow Magpie — Thu, 08 Sep 2011 19:37:01 +0000

Cranky, cantankerous and ill-tempered are some of the words associated with the workhorse of the arid lands. While all of this is true there is much more to the camel than just these few, negative connotations.

The camel can be considered the world’s most successful species when it comes to adaptation. It has managed to not just survive but thrive in some of the driest, harshest and most extreme conditions on the planet.

How the camel can do this is extraordinary. The natural process of evolution has created a living creature so well adapted to deserts that it can survive in environments where virtually all other animals would die.

The Pelmet And Cooling

One of the most immediate problems to deal with in a desert is the heat from the Sun’s rays. Camels overcome this dilemma by some very clever adaptations. The sun-baked soils of these regions can be intolerably hot, enough to instantly fry eggs. Lying down to rest could be highly dangerous. Camels get around this by supporting their entire bodyweight on their pelmet. This is a mound near their chest bone. The pelmet keeps their bodies away from the ground and allows currents of air to circulate, cooling them.

It’s All About The Hump

Perhaps the most famous characteristic of a camel, the hump has two functions. It stores fat and it acts as an insulator keeping the internal organs protected from the heat. The reason camels have humps is because of their lifestyle. They can go for long periods of time without food and consequently need to rely upon a fat deposit for food.

The reason the fat deposits in a single place is to do with heat retention. Camels have two options when it comes to storing fat. They can either coat the entire upper body in a layer of fat which is far from ideal for high temperatures. The other choice is to consolidate all of the fat deposits in one place. The most efficient option was to have hump.

There are two types of camels, those with two humps, the bactrian and those with one, the dromedary.

Water And Conservation

The soaring heat creates grave problems for mammals. Normally, heat stroke would result in such conditions. However, camels keep their brains cool by breathing in cool air, circulating air through a duct that cools down a network of blood capillaries near the brain. This system keeps their most important organ from overheating at all times.

The most valuable commodity for all life, second only to oxygen, is water. Water is highly scarce in arid lands and conserving it plays a crucial role in survival. Faced with such a harsh climate, the ability to frugal use water as efficiently as possible becomes highly valuable. Camels constantly recycle water. Their stomach is lined with folds of skin to absorb as much water and nutrients as possible.

The bladder of a camel is very small, much smaller than a human’s. This is all the more astonishing given the fact that these animals are eight times heavier than us. Camels are so efficient at conserving water that they can go without it for up to six months. They chew the cud, regurgitating their food to maximise the amount of nutrients and water they can obtain from it. Camel droppings are so dry that herders collect them to use for lighting fires.

Unusual Blood

Camels can drink vast amounts of water in a single sitting. It can consume over one/third its entire bodyweight or over 100 litres of water during one of these sessions. To put this in context, a human could kill themselves if they consume more than two and a half litres in one go. This happens because the red blood cells explode due to excess water.

So how can camels consume such large quantities of water? The answer to this question lies in the structure of their cells. Human red blood cells are disc-shaped. The cells of camels however, are elongated and retain their shape when water courses through the blood. They are the only mammal to have these elongated, oval cells.

Unusual Origins

Many people assume that these humped creatures originated in Africa or the Middle East. The truth is very different. Camels originally came from North America immigrating to South America. While in South America these early camels formed different species alpacas, llamas and the modern camel, the camel in turn travelled back up to North America, along Siberia and made its way towards the Middle East and North Africa.

Camels are immensely strong and the nickname ‘ship of the desert’ is highly apt. They can carry several hundred kilogrammes on their backs. In fact, some camels have been recorded carrying small stripped-out cars. There is also undoubtedly a very dark side to their nature. This is something that goes far beyond their well-documented ill-mannered temper.

Violent Impulses

Camels can be incredibly violent. Males can kill one another by crushing the head of its victim. Weighing up to 600 kilogrammes, adult males are far from light. This gruesome act doesn’t just happen in the wild. It can occur right in front of the eyes of the camel owner. Given the large size of camels there is little the owner can do about it.

Their legs are also surprisingly flexible aided by hips which allow a wide range of movement. They use their legs to bring down their victim. Once on the ground the camel is defenceless against its opponent.

Frugality And Efficiency

Efficiency and the conservation of energy are two things that are embedded into the fabric of camels. Their stride is remarkably efficient. They can maintain a sweeping stride, moving one side of their body in unison, then the other. This pattern allows them to use as little energy as possible. The soles of their feet are protected from the constant vibration by a shock absorbing material which protects their joints.

Camels have also got one more trick up their sleeve when it comes to recouping lost energy. Their Achilles tendon is incredibly strong and elastic. This characteristic allows camels to recover up to 50 per cent of energy while moving that would be otherwise lost.

Animals that live in dry, hot lands frequently experience droughts and cannot afford to be choosy eaters. Camels can eat most vegetation. Their cleft upper lip and a highly dexterous tongue allows them to eat plants and leaves that can be difficult for other animals to eat.

Vital Statistics

Camels can be up to 2 metres (seven feet) or more at the hump in height.
Adult males can weigh up to 650 kilogrammes.
Camels are found in Australia, throughout North Africa, the Middle East and parts of South America.
They can live to be up to 50 years old.

http://www.youtube.com/watch?v=WdnPQrqniIE

Highly Recommended

Inside Nature’s Giants is a well-shot Channel 4 documentary. From September 2011 a book will be available covering the animals shown in the series.

You can get Inside Nature’s Giants from here.

Amazon.co.uk
For people living in Ireland or the United Kingdom, you can access: Inside Nature’s Giants from here.

Amazon.ca
For those who live in Canada, you can obtain: Inside Natures Giants here.

Amazon.de
For Germany: Inside Nature’s Giants.

Amazon.fr
For France: Inside Nature’s Giants.

The Tiger: Camouflaged King Of The Jungle

Yellow Magpie — Sat, 06 Aug 2011 12:06:08 +0000

The burning midday Sun is trying its utmost to upset the residents of the forest. Its sweltering heat appears to be causing the air to sweat. A faint flicker of light and a massive creature slinks out of the shadows as its claws and eyes lock on its target. The most powerful of all the big cats, the tiger is the not a force to be crossed.

The Key Differences Between Tigers And Lions

The tiger is both diurnal and solitary which immediately distinguishes it from the lion which is nocturnal and social.
Tigers are found scattered throughout parts of Asia but were never found in Africa.

Unlike lionesses which have been observed displaying natural maternal instincts tigresses have to learn parenting skills and can initially be very clumsy when taking care of their young. It seems that tigers solitary nature may have something to do with this difference.

All tigers are very fond of water and bathing which belies their cold-climate origins. They need to constantly cool down in hot weather. Lions on the other hand dislike water and are much more tolerant of high temperatures.

Camouflaged Killers

Tiger’s stripes provide ideal camouflage in the jungle and wooded areas in which they inhabit. Almost exclusive day-hunters, their ability to blend into the background and avoid detection until the very last minute allows them to be supreme hunters.

Tigers Versus Lions

Although people generally associate male lions as being the strongest of the large cats, this is erroneous. Male tigers are actually stronger possessing more muscle mass than similar sized lions. The largest wild cat, the Siberian Tiger, dwarfs adult lions, and is far stronger.

So if a lion and tiger do come into conflict with each other in captivity all things being equal the tiger will emerge victorious.

Ligers And Tiglons

For centuries people have experimented with tigers and lions by crossbreeding the two distinct species. Although this practice is firmly discouraged by respected zoos, breeders still persist. The hybrid that results is the largest of all the cats. Ligers and Tiglons.

Ligers are a cross between a male lion and a female tigress while the rarer tiglons are a male tiger, female lion mix.

White Tigers: The Dangers Of Inbreeding

Due to their exotic coats and their rarity, White Tigers are a highly popular draw for people.

The most common white tiger is the Bengal Tiger subspecies. Their white appearance is caused by a recessive gene. There have been accusations of inbreeding by breeders trying to obtain the highly desired white coats.

It is worth taking note that three of the most famous tiger attacks on humans were caused by White Bengal Tigers resulting in three people being killed and one seriously injured. In 1998 Joy Holiday and Chuck Lizza were killed by the same White Tiger in separate incidents.

In 2003 Roy Horn of Siegfried and Roy was seriously injured after being attacked by his White Bengal Tiger, Montecore. In 2009 at Zion Wildlife Park, New Zealand, Dalu Mncube was killed by ‘Abu’, a White Tiger. Zion Wildlife Park was founded by Craig Busch, the ‘Lion Man’.

In the HBO documentary, also broadcast on Channel 4, Cat Dancers, Ron Holiday the wife of Joy, stated that he believed the tiger that killed both his wife and partner was inbred.

Human Conflict

The fact that tigers are mostly active during the day, coinciding with human activity inevitable means conflict between the two animals. Tigers have killed more people than any other cat. There are three main reasons for these attacks:

People can encroach on the tiger’s territory causing the animal to lash out defensively.
Old or infirm tigers often have difficulty catching their normal prey and resort to hunting people as they are easier to kill.
The tiger’s habitat is becoming endangered as more and more land is needed for agriculture and other commercial functions.

Tigers are also wanted for their ‘medicinal’ properties particular in superstitious Chinese medicine. There is no scientific evidence for this whatsoever and it seems the chances of these ‘medicines’ providing effective medication is remote.

Tigers are also being continually hunted by people and an entire subspecies have become extinct due to human ignorance.

Vital Statistics

Tigers vary according to the sub-species, male Siberian Tigers can be over 3.5 metres (12 feet in length). Smaller tigers can be over 2.8 metres (nine feet) in length.
The Siberian tiger can weigh as much as 300 kilogrammes (650 lbs).
Tigers can live to be up to 15 years old while captive ones can live to be 20 years or more.
They are found scattered throughout Asia in India, Indonesia and parts of China.

http://www.youtube.com/watch?v=oJ-KzdRsQC4

Highly Recommended

Check out Yellow Magpie’s The Lion: King Of The Savannah to check out the Tiger’s feline relative.

Cat Dancers is an engrossing film about the Holidays who had a famous exotic animals act during the 1980′s and 90′s until tragedy befell them.

Tigers is a superbly well-written book by Steven Mills. Charting the peculiarities of the impressive Tiger it provides wonderful insight into these animals. It also contains some amazing photos that will leave you astounded at how well tigers can camouflage themselves as well as an excellent guide on where tigers are located in the wild.

Cat Dancers and Tiger are available here from Amazon.

Amazon.co.uk
For people living in Ireland or the United Kingdom, you can access: Cat Dancers from here.

The Lion: King Of The Savannah

Yellow Magpie — Wed, 20 Jul 2011 23:18:19 +0000

A man wisely cowers in the undergrowth on a sultry, but rapidly cooling, evening deep in the heart of Tanzania’s savannah. He hears the cracking of the long grass, and is immediately hit in the pit of his stomach by a hellish sound that reverberates throughout his body.

Fortunately for the man, the orchestrator of this fearsome explosion of sound is not interested in him. Without even being seen, using sound alone, the lion has declared himself ruler of the savannah on this occasion.

The Power Of A Roar

Male lions possess one of the most terrifying roars of all the animals. It can be heard for miles around and one of its main purposes is to intimidate other male lions.

Lions achieve this sound through a remarkable larynx. This larynx is very different from the domestic cat and is actually far closer to a human’s. Lions are able to achieve their thunderous roar by pulling the larynx down, amplifying the sound by extending the vocal tract.

The muscles that pull the larynx down are located deep within the chest cavity. These unique abilities allow the lion to project its roar eight to nine kilometres (five to six miles). Males use their roars for communicating many different things. These sounds can be used as invitations for females in the area to mate, they could be to warn off other males or signal a challenge to their rivals.

Lions And Tigers

There are quite a few differences between lions and tigers, most are behavioural. Unlike lions, tigers are solitary animals and only meet other tigers to mate. While lions dislike water, tigers prefer to bathe. This is probably due to the fact that tigers originally come from much colder climates and do not deal with heat as well as lions.

Lions are nocturnal hunters while tigers hunt in daylight. These is probably the reason why tigers have killed more people than any other big cat.

Physically, there is a great disparity between lions and lionesses with the females being much smaller. The physical distinction in size between male and female tigers is not as pronounced in many of the smaller sub-species but is significant in the larger variants such as the Siberian tiger.

All In The Pride

Lions are very social animals. At the heart of their societies is the pride which consists of related females, their cubs and several young males. Each pride has a dominant male who is the leader of the group.

It is very seldom that the alpha male hunts, preferring to leave the work to the lionesses. Instead the dominant male spends his time protecting the pride from other intruders and warding off challengers from male pretenders to his title.

The lionesses generally remove themselves from the pride when they are giving birth and it usually takes several months before their cubs are big enough to be introduced to the pride.

The Hyena Myth

There is a pervading myth that hyenas are scavengers who steal from lions. It goes something like this. The lionesses do all the hard work, stalking and finally killing their prey, only to be overpowered by a larger number of hyenas who force the lions to abandon their kills.

These types of scenarios are often shown on wildlife documentaries so it is not amazing to find out that many people have this view of lion/hyena interaction.

The true role of this complex relationship is far different. It is usually the lions that do the scavenging, allowing the hyenas to carry out the challenging work of hunting and killing the prey. The lions then rush in and take the kill from the dogs.

Male lions have also been known to attack and kill hyenas without provocation and leave the dead bodies uneaten as well as killing hyena cubs. For these reasons, it is little wonder that the two species do not get along.

Man-Eating Lions

When imperialists where colonising Africa, rumours from the native people about man-eating lions would permeate throughout towns and villages. Many of these concerns were dismissed as stories, fanciful tales told to entertain at camp fires.

Nevertheless, at the end of the 19th century and during the beginning of the 20th, these myths became clothed in truths. Several lions that had killed dozens of people were hunted. Two male lions killed 28 people while they were building a railway track in Tsavo, Kenya. The two lions were eventually killed and hunted, with great difficulty, their remains are now on display in a museum. See below.

Gradually, a picture began to emerge of differences in these man-eating lions. All of them were males, all were without manes, and all of them had tooth problems.

Despite some people suggesting that humans encroaching on their territories have forced lions to hunt people, there remains scant substantial evidence to back this up. On the other hand, there is plenty of documented evidence to suggest that some lions that are too weak to hunt their natural prey may resort to hunting people instead.

Undoubtedly, the largest amount of human fatalities was caused by one particular pride of lions that were finally hunted down and killed in the 1940s. It is estimated that three generations of the pride killed an estimated 1,500 to 2,000 people in what is modern day Tanzania.

King Of The Savannah

Lions are a remarkable creatures that are best respected for what they are, highly adept hunters. Their social skills and their ability to communicate is central to their way of life. Lions prides are unique among big cats and demonstrate a culture that sets them apart from other felines.

It seems that lions are destined to remain, for the foreseeable future at least, Kings of the Savannah.

Vital Statistics

There is a high degree of sexual dimorphism between lions and lionesses. Therefore, males are much larger than the females; 2.5 metres (eight feet) as opposed to 1.7 metres (five and a half feet).
The males can weigh up to 250 kilogrammes (550 lbs) while females can weigh up to 180 kilogrammes (400 lbs).
In the wild, lions live up to 15 years, with males often living substantially less due to injuries sustained by fighting other lions. In captivity, lions can live to be as old as 25 years.
They are found in sub-Saharan Africa and in select parts of India.

http://www.youtube.com/watch?v=rbIKMHhoBYs

Highly Recommended Reading

Born Wild: The Extraordinary Story of One Man’s Passion for Africa is a highly recommended book. Containing a heartfelt account by a lion conservationist it delivers a view of lions that others seldom receive.

Amazon.co.uk
For people living in Ireland or the United Kingdom, you can access: Born Wild: The Extraordinary Story of One Man’s Passion for Lions and for Africa. from here.

Amazon.ca
For those who live in Canada, you can obtain: Born Wild
here.

Amazon.de
For Germany: Born Wild
.

Amazon.fr
For France: Born Wild: The Extraordinary Story of One Man’s Passion for Africa.

The Giraffe: A Peculiar Giant

Yellow Magpie — Thu, 14 Jul 2011 22:46:52 +0000

A small simian rests itself in a thick tree, secure in the knowledge that it is safe. A noise startles it but it remains confident in its choice of location. A rapidly-moving, snake-like appendage pierces through the green and the terrified monkey scuttles away.

It is the tongue of a giraffe, one of the only animals with the capabilities to reach such an awkward spot.

Giraffes’ bio-mechanical systems are incredibly adapted, perhaps too specialised. They, courtesy of natural selection, have evolved ingenious solutions to some very tricky problems posed by their unusual bodies.

It’s All In The Neck

There are two accepted reasons why giraffes have such long necks. Originally, it was thought that their necks gave them the ability to access areas that other animals could not in order to obtain food. Recently, scientists have begun to rethink this theory.

Keen observers noted that giraffes spent most of their time eating at heights that were between two and four metres, even though some could comfortably feed at six metres.

Elephants can feed at up to five metres which suggests that giraffes’ exclusivity to higher foliage is a marginal advantage. This led scientists to cast doubts on this theory and look elsewhere for a better answer.

They found a more satisfying explanation in sexual selection. Giraffes often use their heads as weapons, utilising their neck to fling themselves at each other. Long napes are especially important to the males, who fight with one another, vying for the females. The longer limb gives them a heavier head and a greater advantage.

Having long necks became very important and evolution selected animals with these preferred characteristics.

http://www.youtube.com/watch?v=C7HCIGFdBt8

A Nape Design

The neck of a giraffe is designed to be naturally upright. It is held up by tendons. Powerful muscles are needed to enable the giraffe to lower their heads. Because the tension on a lowered neck is quite strong, giraffes can catapult their necks back up – this comes in very handy for males fighting other males (necking).

Despite the length of the giraffe’s nape, they only have seven vertebrae, the exact same number as humans and other mammals.

Giraffes also use their long necks to reach deep inside trees, places that other animals cannot reach.

Preferred Diet And Digestive Efficiency

Giraffes preferred food of choice is the Acacia tree and they get access to the leaves by using their remarkably dexterous tongue. Some tongues can be over 50 centimetres (18 inches) in length. Acacia trees are protected by thorns, it takes a highly sensitive and slender tongue to strip the leaves off the branches. Giraffes spend as much as 12 hours a day feeding on trees.

The key to giraffes ability to obtain energy from food resides in their digestive system which is incredibly efficient. Their thin, long intestines absorbs as much of the nutrients as possible.

Performance Lungs

The lungs of a giraffe are very different from human lungs. They can inflate and deflate almost instantaneously allowing the animal to take in huge quantities of oxygen as they gallop. Their galloping motion and their digestive system help to push the air out of their lungs when lots of oxygen is demanded.

Long-necked Complications

The length of a giraffe’s neck means other complications need to be overcome. Such large distances require a highly powerful heart. The muscle wall of the side of the heart that pumps blood to the neck is massive, up to ten centimetres in thickness (three inches).

Giraffes are also the animal with the highest blood pressure. This creates a problem which is exacerbated when the animal is running. That of blood pooling out of the blood vessels and away from vital organs such as the brain. Blood pooling can be fatal and results in fighter pilots blacking out.

Giraffes get over this hurdle by having very thick skin which presses against the blood vessels preventing the blood from sweeping out under extreme pressure.

The final problem that such an unusual body with ultra high blood pressure faces is the danger of damaging its organs from a surge in pressure when the animal lowers its head.

Giraffes deal with this by having a network of blood vessels that alleviates the pressure when the head is lowered. Blood is also prevented from flowing back into the brain by a series of valves located in the jugular vein.

The Skeletal System

The unusual body of giraffes requires very clever adaptations. This is especially true of their skeleton. Their bones are very thick and powerful with elongated limbs. These limbs allow them to move at 50 kilometres per hour (30 miles per hour) which is fast enough for them to outrun most predators.

Even very young giraffes are able to move at these speeds. This is because young giraffes are born with very long legs, nearly one and half metres (five feet). Adults have legs that are two metres long (six and a half feet).

A Peculiar Patch

The patches on giraffes serve dual functions. The colours provide the giraffe with camouflage helping to make the animal harder to spot and therefore safer from predators.

The second function has only recently being discovered. The patches act as a cooling mechanism to help the giraffe to lose excessive body heat. Each patch is surrounded by a large blood vessel which fills the patch with a network of smaller blood vessels. The overarching theory behind these patches is that they allow the animal to spend longer periods of time eating. With this cooling system the animal is not thwarted by the hot rays of the Sun.

Giraffes are the paradigm of evolution. Their long limbs meant they have had severe engineering problems to overcome which they have done so successfully. Nonetheless, this is an animal that has become so specialised that its future is quite precarious. It is unlikely that such an animal will be around for long.

Vital Statistics

Giraffes can be over five metres (18 feet) high.
They can weigh 1,900 kilogrammes (4,200 lbs).
Giraffes usually live up to 20 years but some have been known to live as long as 24 or 25 years.
They are found in Africa.

http://www.youtube.com/watch?v=KnnG9m4q3aU

Highly Recommended

Inside Nature’s Giants is a well-shot Channel 4 documentary. From September 2011 a book will be available covering the animals shown in the series.

You can get Inside Nature’s Giants from here.

Amazon.co.uk
For people living in Ireland or the United Kingdom, you can access: Inside Nature’s Giants from here.

Amazon.ca
For those who live in Canada, you can obtain: Inside Natures Giants here.

Amazon.de
For Germany: Inside Nature’s Giants.

Amazon.fr
For France: Inside Nature’s Giants.

The Polar Bear: An Indicator Of A Failing World?

Yellow Magpie — Wed, 06 Jul 2011 22:30:29 +0000

The polar bear is the largest land carnivore in the world. Although a supremely powerful animal, what is most striking about this creature is not its size but the fact it has thrived where it is. These animals are amazingly adapted for the harsh land that is the Arctic. Sadly, the polar bear may be on the decline and an early indicator of the deteriorating health of the world’s ecosystem.

The Evolution Of A Top Predator

Scientists still do not know how the polar bear evolved. Their icy environments means that polar bear fossils are almost impossible to find. DNA evidence suggests that roughly 200,000 years ago brown bears, who were found throughout much of the world, were trapped by the encroaching ice sheets in Siberia during one of the Earth’s many ice ages.

Surrounded by ice, the brown bears were forced to adapt and so became the polar bears that we recognise today. The colour of their fur changed to help them to avoid being seen by seals and their ears grew smaller to help with the much colder climate of the arctic.

The Start Of A Worrying Trend?

Scientists have begun to notice that some polar bears are displaying unusual characteristics – deformities. They set about trying to find the root cause as to why these abnormalities were appearing.

It is thought one of the main reasons for this is human-caused pollutants which accumulate as they move up the food chain. Although we may believe that these pollutants are not affecting us the truth is far different.

Phytoplankton, a mico-organism, produce nearly half of the world’s oxygen through photosynthesis - the other half comes from plants and trees. However, they are even more important to our climate as they absorb vast quantities of carbon dioxide which is responsible for our current global warming. Check out Yellow Magpie’s The Melting Ice: The Harsh Reality Of Global Warming for further insight. Without phytoplankton it is arguable that the Earth would not be able to support life as we know it. These organisms are being affected by human pollution.

What has this to do with the polar bear? Ultimately, because these bears are top predators anything that happens in the lower food chains has even more dramatic consequences for them as the effects are magnified the higher up in the chain you go. Polar bears are the apex predators in the Arctic region.

The White Coat That Isn’t White

Polar bears are so well insulated that the lose very little heat. This is the key to their survival in one of the coldest places on Earth. This ability to tolerate extremely cold condition of less than minus 60 degrees Celsius (minus 80 degrees Fahrenheit) is underlined by the realisation that these animals do not hibernate in winter. Perhaps the most remarkable attribute of their tolerance of cold is that they can regularly swim in water that is just above freezing point.

A larger body mass also helps to conserve as much heat as possible. Composed of two layers a soft-underlayer which keeps the bear well-insulated and a longer outer layer of guard hairs which keep water and snow from reaching the inner layer. Underneath the layers of fur is black skin which helps to absorb the sun.

The individual hairs are actually hollow but more startlingly they are clear not white. The appear from from the surrounding snow and sky. This colourlessness is also critical for warmth because white surfaces reflect heat. The clear fur thus passes on heat to the black skin which absorbs the heat of the sun’s light. The skin the radiates heat, warming up the trapped layers of air between the fur and this is what keeps the polar bear warm.

An Animal Of Adaptation

The skulls of polar bears are very different from other bears. Unlike other bears, the polar bears head is long and thin, allowing them to stick their heads into narrow holes in pursuit of seals.

Polar bears store a lot of fat which helps them to survive in lean times. Large polar bears can eat as much as 50 kilograms (120 lbs in one meal) of animal fat. An extensive network of blood vessels along the digestive tract absorb virtually all of the fat they obtain from seals. Because the fat is such a high source of food, polar bears will often leave their preys muscle untouched.

Eating such huge quantities of fat should pose significant problems for polar bears. To prevent heart disease and high cholesterol. Polar bears produce a potent amount of bile which allow them to digest fat safely.

An Early Warning System For A Planet In Distress

Pollution is having a devastating effect on polar bears and damaging virtually all of their biological systems. Male polar bears that have been examined show deformities in their testis and penile bones as well as lesions as shown by Channel 4′s Inside Nature’s Giants. Some polar bears are displaying all the hallmarks of being hermaphrodites or intersex. All of these changes are gravely threatening their chances of reproduction and survival.

Scientists maintain that PCBs (polychlorinated biphenyl), which are found in many plastics, are one of the biggest contributors to the plight of both the polar bears and the planet. PCBs act in much the same way as dioxins do. Dioxins mutate the cells and cause abnormalities in the reproductive system. PCBs also cause problems for the immune system and, like dioxins, accumulate in fatty tissue.

Since the 1930′s companies have known that about PCBs’ toxicity. Since 2000 virtually all types of production of PCB has been outlawed. Although its effects could still be causing damage.

PCBs are just one type of persistent organic pollutants (POP) – the role of these group of chemical agents has yet to be understood and the substances themselves are still awaiting classification. It is POPs that most have scientific researchers worried.

Polar bears are an indicator of the deteriorating state of the world’s ecosystem mainly due to the fact they eat such large amounts of fat. These animals, as top predators, may be the first of many to suffer from POPs unless we get our manufacturing processes as safe as possible.

Vital Statistics

Polar bears can be as long as three metres (ten feet).
They can weigh as much as 800 kilogrammes (1,700 lbs). Adult females are usually at least half the size as adult males.
Polar bears can live to be as old as 25 years. The oldest recorded bear was 43-year-old female.
They are found only in the Arctic region.

http://www.youtube.com/watch?v=zm8eHSIoXDE

Mink: The Most Vicious Of All Animals?

Yellow Magpie — Wed, 29 Jun 2011 16:37:27 +0000

Shadows flicker and move causing confusion. Is there something stalking unseen? Or could it just be the wind pushing against the grass. A moving branch throbs and a blur comes pouring out seizing its unsuspecting prey in a lethal embrace of tooth and claw.

This slender, sinewy creature stalks the undergrowth of a riverbed. It is remorseless and will attack anything regardless of size. This is the mink, the true psychopath of the animal kingdom.

Territorial Predators

Mink are very keen on territory. They will attack any other mink that unwisely enters their realm. Although some males have been known to tolerate females in their territory.

Minks always live very close to water. They frequently live beside rivers and marsh land.

The Two Types

There are two different species of mink. The European Mink is a native of central Europe and Russia. This species is endangered and is perilously close to becoming extinct. One of the main reasons for this is the introduction of the larger, American Mink into Europe. The American mink is much more suitable for the fur trade.

The Fur Trade

American Mink is farmed extensively for the multi-billion euro fur trade industry. These animals are the most important contributor and individual pelts can be worth up to €70. The largest importer of fur is China. However, the United States is not far behind with in excess of one billion euro spent on fur, much of it mink, last year alone.

Every year 50 million mink pelts are produced with Denmark, the world largest farmers of the animal, leading the way with 14 million.

Far from being an industry in decline the global fur trade is thriving and mink is the cornerstone.

The Lethal Nature Of Mink

Mink is an animal that should not be underestimated. They are extremely violent and will attack almost anything. Although very rare, mink have also attacked fully-grown adults in unprovoked incidents.

Breeders of mink must keep the animals in separate cages as they will kill and eat one another. Despite all of the years of domestication, mink are still not tame and must be handled with protective gloves by the farmers.

The Devastating Release Into The Wild

In the 1990′s the fur trade industry went into a sharp decline as animal rights activists succeeded in alerting people to their cause. Fur became deeply unpopular as a consequence and the demand for mink fur was greatly reduced.

Animal rights liberators broke into mink farms in the 1990′s and released the mink into the wild. However, there have been also unconfirmed reports that some farmers released them as they could no longer afford to keep the animals without any prospect of return.

Whoever was responsible, the consequences of releasing the invasive mink has been devastating for the local wildlife. American mink is endangering stock of native fish and also native animals, especially those that live close to the water’s edge.

In 2010, when the mink fur market was strong, 5,000 mink were released into the wild by animal rights activists in Donegal, Ireland, during the salmon breeding season. These hard-core activists have caused untold damage to local wildlife and the true picture of the mink’s impact will only begin to emerge in the coming decades.

Vital Statistics

Minks can be up to 60 centimetres (24 inches) in length.
They can weigh in excess of one kilogram (two lbs) in the wild while farmed mink can weigh 3 kg (seven lbs).
Mink can live for over ten years.
They are found in temperate regions such as North America, Europe, Siberia and Ireland.

http://www.youtube.com/watch?v=WdTr8kjdNuI

Hedgehog: Capturing The Human

Yellow Magpie — Wed, 15 Jun 2011 18:43:51 +0000

These spiked creatures amuse us. For something that can cause quite a sharp pain if they are touched – they are perhaps an unusual fascination that draws our attention.

Hedgehogs are nocturnal by nature and spend their nights pottering around hoovering up insects. When threatened these animals retreat into a spiky ball that offers them protection from most predators.

The instantly noticeable attribute that hedgehogs possess are of course their spines. Each hedgehog has between five and seven thousand spines that form their defences.

Farmers’ Best Friend

Hedgehogs eat many pests that destroy vegetables and crops. A single hedgehog may eat hundreds of insects during the course of one night. As a result many are welcomed into farms and gardens.

The African Pygmy Hedgehog

The African Pygmy Hedgehog is adapted to very different conditions than its cousin, the European hedgehog.

A good deal smaller, the pygmy, or North African hedgehog as they are also called, live in harsher dry lands than the European variety. As the name suggests, they are found in North Africa but they are also inhabit Spain and France.

These creatures live in relatively small circular territories of up to 2,000 metres (1,200 feet).

Human Dangers That Hedgehogs Face

One of the most common causes of the premature death of hedgehogs are insecticides and pesticides. This is due mainly to the fact that hedgehogs consume a large quantity of insects and molluscs which are often laced with poison. The cumulative effects of consuming such large amounts of poison is enough to kill the hedgehog.

Cattle gates with open gaps are also a major hazard for hedgehogs who sometimes get trapped after falling into the recess. If this happens the hedgehog will simply starve to death.

Tennis court nets can frequently become a major hazard for the spiky mammal. This is also true for other forms of netting including those designed to keep birds away from fruit and vegetables growing in the garden.

However, by far the most dangerous man-made threat to hedgehogs are cars. Every year a hundreds of Hedgehogs are killed in Ireland alone.

A Diseased Creature

In many ways, Hedgehogs are like humans when it comes to being disease prone. They suffer from heart disease, probably caused by a poor diet scavenged from human sources.

Cancer is especially prevalent in hedgehogs. For this reason, scientists are very keen to research these animals.

Hedgehogs: The New Dog

A new fad, especially in North America, is to adopt hedgehogs as pets. Humans find these creatures cute and an entire industry has sprung up to cater for this rapidly emerging market. Companies have even been created to make food designed specifically for a hedgehog diet.

In Ireland and the United Kingdom it is illegal to keep the European Hedgehog as a pet as they are on the endangered species list.

Vital Statistics

Hedgehogs can be up to 30 centimetres (12 inches) in length.
They can weigh in excess of one kilogram (three lbs).
Some hedgehogs can live to be 16 years or more but they usually average seven to eight years for larger species and four to five years for smaller ones.
They are found in Europe, Africa, Australia and New Zealand. The hedgehog is not native to North America.

Highly Recommended Reading

You can obtain The Hedgehog: An Owner’s Guide to a Happy Healthy Pet here from Amazon.

Amazon.co.uk
For people living in Ireland or the United Kingdom, you can access: The Hedgehog: An Owner’s Guide to a Happy Healthy Petfrom here.

Amazon.ca
For those who live in Canada, you can obtain: The Hedgehog: An Owner’s Guide to a Happy Healthy Pet here.

Amazon.de
For Germany: The Hedgehog: An Owner’s Guide to a Happy Healthy Pet.

Amazon.fr
For France: The Hedgehog: An Owner’s Guide to a Happy, Healthy Pet.

The Squirrel: A Varied And Clever Creature

Yellow Magpie — Wed, 01 Jun 2011 23:51:08 +0000

Fleet of foot, the squirrel is an arresting creature that displays presence of mind and great planning in its bid for survival. Their terrific memories and adaptability makes these animals extremely interesting.

Squirrels are a sub-group of rodents. There are thought to be at least 278 different species which include groundhogs and prairie dogs.

It’s All In The Tooth

Like the beaver, squirrels have self-sharpening teeth. They do most of their biting with their large incisors which grow continuously. The teeth are composed or two layers, the front is made of enamel while the back is composed of softer dentine. The dentine layer wears away first and because of this the teeth stay sharp.

They use their chisel-like teeth for eating and gnawing at tough materials like hazelnuts.

Similar Hands But Amazing Feet

The hands of squirrels are remarkably similar to our own. They have five digits and a rather small thumb on each hand. However, the ratios of the hands are much different from ours and their palms are relatively modest in comparison to the length of their fingers.

Depending on the species, the width of their hands varies. For instance, the burrowing squirrel’s hands are much wider than that of the tree squirrel. Which, no doubt, helps to assist digging.

What is truly astonishing is squirrels ability to turn their feet when climbing down. Whereas people normally can only move their ankles a few degrees without moving their legs, squirrels can move theirs 180 degrees independently of their feet. This feat is accomplished by unusually flexible ankle joints which allows the squirrel to descend smoothly.

The Difference Their Tails Make

The tail of a squirrel may be its single most important limb. While jumping they use their them as rudders to guide their direction. The tail also plays a critical role in climbing trees, helping the squirrel to control its centre of balance and keep a good footing.

If a squirrel falls, and they sometimes do, their tails act as parachutes reducing the free-fall speed. The tail also acts as a cushion protecting their delicate bones from a hard landing.

Nonetheless, there is more to squirrels’ tails than just balance and safety. Squirrels tails play a critical role in thermoregulation. Normally rodents tails are conical, as opposed to bushy like a squirrels, and have a lot of surface area but little volume. Rodents tails are rich in blood networks and squirrels are no exception.

Generally, this means that rodents lose a lot of heat through their tails which can cause problems in winter. Squirrels can control the temperature of their blood flowing through the tail. In winter their tails are supplied with cold blood which means there is minimal heat loss. While in summer the opposite occurs and they send warm blood through the appendage to cool them down.

What Do They Eat?

Squirrels generally eat nuts and tree buds. They cannot digest cellulose so eating grasses and such matter is out for them.

During the spring, when the nuts that they have collected start to sprout, they must look for an alternative food source. They usually choose to eat tree buds during this period.

There has been documented evidence of some squirrels eating infant squirrels, although this is thought to be rare. Other researchers have found small vertebrates such as lizards and rodents inside the stomachs of squirrels.

How Do They Remember Where They Stashed Their Food?

Squirrels are renowned for the nut-collecting behaviour. It is thought that they store their nuts in different places to prevent all of their food from being eaten. If one is discovered by a predator or rival the squirrel doesn’t lose its entire hoard.

They sometimes store nuts temporarily only to move them to a more permanent location. This is called ‘scatter hoarding’. Their long-term stores are sometimes called ‘larder hoards’.

This charming video explains how squirrels remember locations:

http://www.youtube.com/watch?v=sMYuIK5YWVE

Red Versus Grey

In Ireland, as well as in the United Kingdom, there are two types of squirrels, the native red and the recently introduced grey. The grey is considered to be a pest in both areas and are actively culled as they are impacting upon the numbers of native red squirrels.

The grey squirrels also do damage to trees. Although, as of yet, it is still not known why they do this.

Communication

Squirrels are highly intelligent mammals. One of the hallmarks of intelligence is the ability to communicate. Squirrels do this through high pitched chatter using shrill sounds. They also use their tails to ‘talk’ to one another. Rapid flicking usually is a warning for other squirrels to keep their distance.

Colour Vision?

Squirrels are thought to be dichromatic.

Most people are trichromatic, we see through three different colour filters, red, blue and green. Dichromatic people and other animals are missing the green filter and therefore have red/green color blindness. As a consequence of this, squirrels cannot see colour in 3D.

Here is the a picture of the colours of the rainbow seen from the perspective of a squirrel.

Vital Statistics

Squirrels can be different sizes according to the species. The smallest, the African Pygmy Squirrel, is only eight to ten centimetres (three inches) in length. While Groundhogs, a type of Marmot, can be over 80 cm in length (two feet six inches).
They also vary in weight depending upon the species. One of the largest, the Groundhog, weighs up to 18 kilograms (31 lbs).
In the wild, squirrels usually live up seven or eight years. In captivity they can live to be as old as twenty.
They are found in every continent with the exception of Antarctica. Recently they have been introduced into Australia, where they are not native.

http://www.youtube.com/watch?v=TamMqvk4Bb8

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The Sloth: A Slow-Moving Oddity

Yellow Magpie — Wed, 25 May 2011 16:15:31 +0000

It is one of the strangest mammals found in nature. An exotic lumbering creature that spends a lot of its time sleeping and the rest of it either resting or seemingly moving in slow-motion. The sloth is an animal of intrigue. Its alien appearance gets our initial attention but it is its inability to move quickly that sustains our gaze.

Sleeping Sloths

Sloths are generally thought to be among the most somnolent animals that exist today and they spend the vast majority of their lives sleeping. They can appear to be asleep for up to 18 hours of the day.

Recently the Max Planck Institute in Germany has found that sloths spend as little as ten hours or less actually sleeping. They obtained this information from analysing the animals sleeping patterns. Therefore, it appears that the animal is sometimes not actually asleep when it has its eyes firmly shut.

A Low Energy Lifestyle

The reason why they spend so much time in a low-energy state is because of their diet. Sloths are leaf-eaters. Leaves are an abundant form of food in the rainforests and it is natural that animals would use them as a food source. Nonetheless, leaves have a serious drawback especially if they feed on them exclusively. They are a low energy food.

To compensate for this sloths have adopted a very lethargic lifestyle. They spend most of their time barely moving. To highlight just how slow-paced their lives are, sloths only defecate either every week or every fortnight.

But Why So Slow?

The most piquing aspect of sloths is their speed, or more precisely their lack of it. On the ground sloths move at an incredibly slow pace of two metres per minute. Even when they are in extreme danger they only manage six metres per minute and this exertion leaves them exhausted.

http://www.youtube.com/watch?v=-tfsL9Kq8R8

The ultimate reason why sloths are slow-paced is because of their diet. The low energy food has resulted in the necessity of having muscles that utilise the least amount of energy. As a result, their muscles are roughly between one-fifth and one-quarter the size of an animal of similar dimensions.

How Are Sloths Still Around?

The question that pervades everyone’s lips is just how have sloths survived extinction. Surely such a slow-moving animal would be easy fodder for predators? It is their slow-moving nature that has allowed sloths to become a successful species. High atop the trees, they are difficult to spot and the fact that they barely move means they receive little or no attention from predators. It is only when they come down to the ground defecating that they are highly vulnerable.

Claws

Claws are very important to sloths. Their long nails allow the sloth to hold on to trees without any energy being exerted. In fact, sloths that have died often remain motionless still clinging to branches.

Sloths also use their claws as a last defence against predators. Though given their slow moving nature it seems that this would only deter predators if they became intimidated.

Strange Visitations

One of the oddest aspect of sloth’s behaviour is the habit of climbing down to the ground to defecate. This odd practice is stringently adhered to by all sloths and the reason why they do so is still unknown. Some scientists have speculated that going to the ground allows them to smell other sloths in the area which is especially useful for mating.

Others have theorised that they are worried about the noise of defecating attracting unwanted attention from predators if they simply remained in the trees. This seems to have veracity as some sloths have been observed defecating from the safety of trees during thunderstorms as the sound would be masked by the thunder.

Vital Statistics

Sloths can be over 60 cm (two feet) in length.
They weigh between three to four kilograms depending upon the species. Two-thirds of their body weight is accounted for by their stomach and digestive organs.
Sloths can live up to twenty years in the wild and up to 40 years in captivity.
They are found in in the rainforests of Central and Southern America.

http://www.youtube.com/watch?v=ndMKTnSRsKM