10.3f – The Potoroids

The unknown marsupials. This is a bettong. (Photo by Noodlesnacks)

The potoroids are a sort of cousin group to the macropods. Essentially, they are all the marsupials you never hear about, such as the bettongs, the potoroos, and the rat-kangaroos. One article will suffice to cover them all.

Potoroids are small, about the size of a rabbit. Their feet aren’t as relatively large as a macropod’s, but they are still suited to hopping and know how to get around. It’s possible that they are the sort of animals that macropods evolved from, but we don’t really know for certain.

While potoroids are plant-eaters just like macropods, they are also known for their love of tasty fungi. Some potoroids eat practically nothing but the fruiting bodies and spores of various species of fungus. This means that they mostly live in moist habitats with lots of thick bush where fungus likes to grow; coincidentally, this sort of habitat also helps protect them from invasive cats and foxes, by giving them lots of hiding places. Many potoroids live in much-reduced areas today compared to the past.

Yet some potoroids, such as the boodie, live in drier areas and burrow underground to keep from drying up during the day. The critically endangered woylie also does well in dry places, and is known for being able to carry small items with its tail while it hops. The woylie eats fungus that grows underground, digging it out with its claws. Both of these aforementioned animals are a type of bettong.

The potoroos are similar, but while the bettongs are shaped like very tiny kangaroos, the potoroos are shaped more like rabbits or big rats. They haven’t done as well as the bettongs, and all of them are threatened or endangered. One species, Gilbert’s potoroo, is the most endangered animal in all of Australia, and there are only about 30 of them known to survive in the wild. This makes it one of the rarest mammals anywhere in the world. In fact, it is so rare that scientists considered it extinct for more than a hundred years until it was re-discovered in 1994.

Also in the potoroid group are two types of rat-kangaroo. The rufous rat-kangaroo is more closely related to the others, and is the biggest potoroid, though that’s not saying much.

More interesting is the musky rat-kangaroo, which some scientists place in its own family. It’s the smallest of the group, less than a foot long. It hops more like a rabbit than a kangaroo, but in some ways it’s a conglomeration of many other Diprotodontia species — it can climb trees like a possum, it can carry more than one joey in its pouch, and it can hop. So what kind of creature of weaponized cuteness do you get when you combine all the traits of other cute marsupials like superheroes combining powers?

“… oh hi there.” (Photo by PanBK)

Apparently you get something that looks like an ugly hopping rat. Go figure.

10.3e – The Tree-Kangaroo

Are they lost, or just very confused? (Photo by Postdif)

There are 12 different types of tree-kangaroos, and they are by far the strangest of the macropods, even if you only consider their evolutionary history.

If you’ll recall, we believe that that the members of Diprotodontia (koalas, wombats, possums, kangaroos, etc.) evolved in trees, which is why their two middle toes are fused together. Eventually some of them came down from the trees and lived on the land instead, including all of the macropods. But then something curious took place. Some of the kangaroos, now living on the land, changed their mind and went back to the trees again.

We think this happened because their ancestors were among the forest-dwelling pademelons (a type of wallaby) that were cut off from all the others by natural forest shrinkage during an ice age. Cut off from other pademelons, they eventually evolved down a different path and returned to the trees, becoming tree-kangaroos.

As you can guess by now, tree-kangaroos are macropods that have adapted for life in the trees. They have completely lost the speed and grace of a kangaroo on the ground; put them on land and they are clumsy and slow, as though they can’t quite figure out what to do with a flat surface. But put them in a tree, and wow.

A tree-kangaroo in a tree is quick and agile, using their strong macropod legs to hop and climb tree trunks and branches like a human with a belt and spiked boots. The animal wraps its arms around the tree limb and shimmies up the tree like an expert. They can also use their powerful jumping powers to literally leap from tree to tree — they can cover a fantastic 30 feet through the air to land in a lower branch in another tree, and can jump down from up to 60 feet up and land on the ground without harm.

Sixty feet? There are superheroes who can’t do that. (Photo by Fred Hsu)

Yes, it’s exactly as weird as it sounds. Essentially they are kangaroos that have started to evolve in the same direction as monkeys. Some of them have even evolved an ability to walk slowly on two legs, because of how their legs are able to rotate in order to allow climbing. They have long tails that help them balance when scrambling along branches. Their hind legs are not quite as enormous as a normal kangaroo’s, but to make up for it their arms are stronger to help them climb.

Most tree-kangaroos live on the island of New Guinea, north of Australia, though some are also found on other small nearby islands and on the extreme northern edge of Australia itself. A handful of tree-kangaroos are endangered, and some others are even critically endangered due to habitat loss and hunting.

But we need to keep them around, and I’ll tell you why. If they’re evolving in a convergent-evolutionary manner in the same direction primates took, how can we resist the urge to give them a few million years and see if they turn out like us? I don’t know about you, but I don’t want to be known as the generation that let the ancestors of a potential race of intelligent kanga-men die off.

10.3c – The Wallaby

A kangaroo by any other size … (Photo by Nino Barbieri)

If you are like me, you may have sometimes wondered what the difference is between a kangaroo and a wallaby. The answer is: size. That’s it. That was easy, wasn’t it?

The word “wallaby” doesn’t refer to a specific related group of animals. There are all sorts of wallabies, but the only thing connecting them is that they are all macropods and they are all smaller than a kangaroo. They are the answer to the question, “What looks like a kangaroo, smells like a kangaroo, jumps like a kangaroo, but isn’t a kangaroo?” And that’s about it as far as wallaby basics go. In almost every respect, a wallaby is essentially nothing more than a small kangaroo.

But that’s not quite the end of it, because there are still some things about wallabies that are of interest. For one, the very fact that they are smaller has a very important consequence. Whereas a kangaroo is big enough to fight off any predator, a wallaby is not, and they can face danger from dingos and even foxes or feral cats. A wallaby can still inflict a mighty kick when it needs to, however.

There are some types of wallabies that a little different from a kangaroo. There are some known as pademelons, and are the very smallest wallabies. They live in forests rather than on the open grazing land that kangaroos and other wallabies prefer. Because of their small size they don’t require the thick, strong tail that kangaroos and bigger wallabies use for balance, and a pademelon’s tail is quite unimpressive by comparison.

Another type are the rock-wallabies, which are sort of like the goats of Australia. They are very agile and have special feet that can grip rocky surfaces. They live in rock piles and cliffs, and have a special fondness for areas with lots of caves and ledges where they can hide. They only leave the safety of the rocks to feed, but many of them have declining populations.

It ain’t easy being a rock-wallaby. But at least they get to play on cliffs all day. (Photo by David Iliff. License: CC-BY-SA 3.0)

There are also small forest-dwelling wallabies that live in New Guinea that are called dorcopsises.

The oddball of the wallabies is the banded hare-wallaby, which is the only surviving member of a very ancient type of macropod. It’s small (about two feet long plus a tail) and barely has any arms. It is thought that it and similar animals were once common in Australia, but they have all died off. The banded hare-wallaby only survives on two small islands off the west coast of Australia, where there are no invasive predators. It is an endangered species.

Wallabies are another of those rare animals that has turned the tables on the whole invasive species gig by invading other places. There are a number of invasive wallaby populations around the world, from animals that escaped captivity and formed feral groups in the wild. You can find random wallaby populations in New Zealand, Hawaii, Ireland, England, and France. These populations typically started from animals that escaped from zoos.

But the real burning question is: if you hit a kangaroo with a shrink ray, could you call it a wannabe wallaby?

10.2e – Leadbeater’s Possum

A tragedy in the trees. (Photo by Pengo)

In the southeastern corner of Australia live perhaps the oldest and rarest of all possums, Leadbeater’s possum. They aren’t named for their ability to work with metals, but rather after an Australian taxidermist named John Leadbeater.

Their story begins in the years between 1867 and 1909, when science learned of this possum through only five specimens collected during that 40-year period. What they learned was that Leadbeater’s possum was a primitive, ancient type of possum that had survived down through the years while others had changed or gone extinct.

A nocturnal creature, the possum lives in family groups of up to 24 animals that nest together in the hollows of trees. However, hollows only form in very old trees, and in order to survive they also needed a constant supply of food. These restrictions kept the old possum species living in a very small area in the old growth forests of southeast Australia.

After 1909 scientists stopped being able to find even the occasional Leadbeater’s possum, and the scientific community figured that the poor old fellows had finally shuffled off to the great tree hollow in the sky.

But in 1961 a Leadbeater’s possum was discovered again, and in 1965 we finally found a whole small colony of them living together. More searches uncovered their whole population range, a small and specific area of the old growth forest where everything was like Baby Bear’s bed for Goldilocks — juuuuuust right.

The problem was that the possums needed trees of a very specific age to live in, and good supplies of fresh greenery to eat. We believe that in the past, the possums always moved on to a new area when the old area got too old. With humans logging much of the forests, the number of new areas to move to has grown steadily fewer as time goes by.

There were about 7500 Leadbeater’s possums by the 1980s, when they were living in an area that had been swept by fires in 1939 — there was good young regrowth and there were old dead trees to live in. But by 2009 they had declined to about 2000 possums as their forest was getting too old and they couldn’t really move anywhere else. That’s when the worst possible thing happened.

In February of 2009 the Black Saturday fires, a series of devastating bush fires in Australia, completely destroyed most of the possum’s remaining habitat, and most of the possums themselves in the process. By the time the smoke cleared, this already-endangered species had only about 100 remaining members.

Combined with continued logging in the region, this means that the possum’s only hope for survival rests in the hands of mankind. Efforts have been made to protect the possum’s area from any logging, but counter-efforts are trying to allow logging regardless of the presence of a critically endangered species. A handful of Leadbeater’s possums have been taken into captivity, but they have proven difficult to breed, though efforts are now being met with some success. But the truth is that there aren’t many left, and even those low numbers are falling. Our efforts may be too late.

7.3c – The Tasmanian Devil

The devil is in the details. (Photo by Noodlesnacks)

If you are like me and grew up with Looney Tunes cartoons, the name Tasmanian Devil brings to mind a whirling, angry, garble-talking beast. This depiction is not quite accurate, but the actual animal, an endangered carnivorous marsupial found on the island of Tasmania, is still every bit as remarkable. Yet sadly, this unique creature is now dying out because of a terrible disease.

The Tasmanian devil is the size of a small dog, but it is the world’s largest carnivorous marsupial now that the thylacine is (probably) extinct. It is fast and strong, it can climb trees and swim rivers, it both hunts and scavenges, it has a tremendously powerful bite, it has a sense of smell like nobody’s business, it in turn smells awful, and it is a loud, angry-sounding creature. So a bit like a deranged, drunk hobo with a knife.

They once lived throughout Australia, but were all killed on the mainland sometime in the past 3000 years, possibly by dingoes, which are feral dogs first brought to Australia by humans.

The childhood of a Tasmanian devil is not an easy one. A female gives birth to a remarkable 20 to 30 young at a time, but she has only four nipples in her pouch, meaning that most of the young will soon die and only the strongest or fastest will live. This is an evolutionary failsafe of sorts, ensuring that the devils stay strong and fast as a species, which they need to compete for food and stay alive.

Once it grows up, however, a Tasmanian devil is a tiny force to be reckoned with. It has a scent gland much like a skunk, which it uses to mark the ground with a powerful, awful odor. Its jaws are so strong that they can crush bones and bite through metal wire. In fact, so much of the animal’s strength is concentrated in its jaws that it has a disproportionately large head, which gives the animal a strange, shambling sort of movement when walking.

Most devils hunt during the night, using their black fur, their sensitive whiskers, their great eyesight, and their ability to smell prey more than half a mile away to their advantage. Some however can hunt during the day, and the Tasmanian devil is one of the few marsupials capable of being active in the Australian midday heat.

Like the quolls, Tasmanian devils are solitary creatures but sometimes feed together and often have communal pooping spots. Unlike many solitary animals, they are not territorial. There can be a large concentration of devils in a small area without any problem; they simply won’t interact any more than they have to, though males will fight during mating season.

When hunting they can be fearsome, taking down small kangaroos or sheep, sometimes fish or fruit or frogs or insects, but most often wombats, and even more often it will simply find some carrion to scavenge and not waste time on hunting. No fool, the Tasmanian devil. When they live near humans, they like to steal shoes and chew on them, and have also been found to eat pencils, plastic, and denim jeans. All right, maybe a little foolish.

"Be honest. Do these pants I ate make my butt look fat?" (Photo by Mike Lehmann)

When a devil finds a meal, it wastes neither time nor opportunity. It will dig in with fervor and gusto, and can eat up to 40 percent of its body weight in one sitting, becoming so fat and bloated that it can only waddle away and find somewhere to lie down. When there are several devils in an area, they can pick a carcass clean before it rots.

In fact, devils seem to like to eat together, even though they normally ignore each other and never so much as wave hello when they pass on the street. But when a devil makes a kill or finds a good meal, it doesn’t mind at all if other devils come and join it. It is perhaps the only carnivore that lives alone but eats in groups. Up to 12 animals will eat at the same kill, and they make loud growling and ripping and eating sounds together, which is what inspired the sounds made by the cartoon character. It is believed that the loud eating noises are a way to advertise to other devils in the area that there is good eating to be had. Tasmanian devils are not greedy.

They are, however, sort of mean. Even though the devils advertise their food, they will squabble with each other when it comes to eating. Older devils will chase younger ones away, and the animals that never talk to each other elsewise are shown to have developed at least 20 different communication postures used while feeding together. They sometimes sumo-wrestle by pushing each other with their paws, and they will bite one another seemingly at random while eating, which is why many devils have scars around their face or rump. They don’t seem to mind. It’s all part of the Tasmanian devil lifestyle.

The devils are endangered for a number of reasons. They were once widely hunted, trapped, and poisoned by farmers, but the population became protected after the extinction of the thylacine, and slowly recovered. Surviving the wrath of humanity, they now sadly suffer from devil facial tumour disease, which is a terrifying affliction.

First appearing in 1996, it is essentially a contagious cancer that has spread across most of Tasmania and only affects Tasmanian devils. Though the original source of the cancer is unknown, it may have started due to human chemicals in the environment that concentrated in the devils, at the top of the food chain. How does it spread? Unfortunately, it mostly spreads when the devils randomly bite each other during feeding, and it is thought that as many as 80 percent of wild devils are currently infected. Sick devils are removed from the population to prevent further spread of the cancer, but there is no known cure. It is killing the devils faster than they are able to reproduce.

It is one of only three known contagious cancers in the world. This extremely rare form of cancer is possible because the cancer cells themselves are transmitted to new hosts, like a virus, and then clone themselves within the new body even though that body’s own cells are healthy. If that sounds terrifying, well, that’s because it is. The other two contagious cancers are the canine transmissible venereal tumour (passed between dogs through sex) and a reticulum cell sarcoma found in the Syrian hamster.

Scientists have gathered healthy devils to keep in captivity as a means of preserving the species in case the wild devils all die from the disease, which unfortunately is likely to be the case if new treatments aren’t found. Scientists are continuing to search for ways to stop the disease. It is estimated that at the current rate, Tasmanian devils would become extinct by 2035, but breeding healthy devils in captivity and quarantine may help the species live on. There are somewhere between 10,000 and 15,000 Tasmanian devils left in the wild.

7.2a – The Numbat

Caught between a fox and a hard place. (Photo by Helenabella)

On top of having a great name, the numbat is a lovely, unique Australian marsupial, and the only living member of its family. It too was almost destroyed, but is being slowly pulled back from the brink of oblivion.

The numbat is also known as the banded anteater, so-called because it has stripes on its back and because the men who discovered it in the early 1800s saw that it had a long tongue for its size, and assumed it must be a type of anteater. In fact it does not eat ants at all. The numbat’s diet consists of one thing, and one thing only — termites. Termites for breakfast, termites for lunch, and termites for dinner. If it gets a midnight craving, there are leftover termites in the fridge.

Even though it is a relatively small creature, about a foot to a foot and a half long, its voracious appetite for termites knows no bounds. An adult numbat will eat up to 20,000 termites per day, which, well, as far as minds go, this boggles them.

Termites are fairly nutritious, but there’s not much to them, and because of this the numbat has a very weak jaw and lots of tiny, useless teeth that it doesn’t even use. You don’t need to be able to chew to eat a termite; they are soft and small.

Yet the numbat is actually not very well-adapted for an all-termite diet. Many animals that are specialized for termites are larger creatures with strong digging claws to rip into a termite mound, and with a very long tongue for reaching down into the depths of the colony. The numbat has very ineffectual claws that can only reach termites near the surface, and its tongue, while long and sticky for an animal of this size, is not nearly long enough to get deep into a termite mound. In evolutionary terms, the numbat brought a knife to a gunfight.

"That's not a knife." This only works if you say it in an Australian accent, which of course all numbats have. (Photo by Martin Pot)

To make up for this, it synchronizes its own daily schedule with the termites’. When the termites are active, there will be many of them near the surface of the mound, allowing the numbat to get them out with its tongue. In the summer, the numbat feeds through the morning and evening, skipping the afternoon heat; in the winter, when the termites are less active, the numbat feeds for only a few hours in the late morning and early afternoon, and spends the rest of the day saving energy by going into a torpor. You might remember that this is a deliberate state of very low energy use, low body temperature, and low metabolism, like a short-term hibernation.

In addition, the numbat has the best eyesight of any marsupial, which helps it to avoid predators such as snakes and hawks. But this eyesight did not help it when a new type of predator came to Australia.

Numbats were once widespread across western and northern Australia, but that all changed when humans deliberately introduced foxes to the country so that they could have fun fox hunts like they enjoyed in England, because nothing says “refined and noble gentleman” like terrorizing a fox. You’ve heard this story before — the foxes bred, their population grew out of control, and the native wildlife of Australia had no defense against them.

Foxes tore into the numbat population and came within a whisker of destroying every single one. The once-widespread creature survived only in two very small pockets in the extreme southwestern corner of Australia, with only about 1000 individuals remaining. It is thought that they survived here because there were a large number of hollow, fallen logs where the numbats could hide from the foxes.

With the great genocidal fox-numbat war close to its ultimate end, humans stepped back in and tried to protect the numbat. We removed as many foxes as we could from their areas, and their population began to improve. The foxes went on to kill other animals instead, and slowly we have begun to reintroduce the numbat to some other small, fox-free regions. Today the numbat is still endangered, but its prospects have improved. The problem of invasive species in Australia, on the other hand, is far from resolved.

Like all marsupials, the numbat gives birth to very tiny, under-developed young. Numbat babies cling to their mother’s underside, because the numbat is one of the rare marsupials that does not have a pouch. The babies hang on down there and feed while the mother goes about her usual termite-devouring business, and they stay there for almost half a year. At that point they are too big to hang off her underside, and so instead they crawl onto her back and continue to hang out up there for another three months, except when the mother gets tired of them and leaves them in the nest so she can finally eat her 20,000 termites in peace.

4.2g – The River Dolphins

Dolphins that dance to a different drummer. These are Amazon river dolphins, or botos. (Photo by Stefanie Triltsch)

River dolphins are a different kettle of fish than the ocean-going dolphins we all know and love. There are three types of river dolphins known to be currently still alive, found in Asia and South America, but these unique animals are having a very hard time.

Though they look mostly similar to marine dolphins, river dolphins are distinctive because of their long, narrow beaks, which can be up to two feet long. This is four times the length of an ocean dolphin’s beak. They use this fantastic, toothy mouth to catch fish. In addition, river dolphins have small eyes and poor eyesight compared to ocean dolphins, because they live in sediment-filled muddy rivers where they rely on echolocation instead of eyes.

In South America you will find the Amazon river dolphin, also called the boto, which lives in both the Amazon river basin and the Orinoco River to the north. It is found along much of the entire length of those rivers, and move up and down as water levels change. Its long mouth is useful for reaching into vegetation and tree roots to pull out hiding prey.

The La Plata dolphin also lives in South America, but is found snugged up against the coast in the southeast of that continent. It does not actually live full time in rivers like the others, but is otherwise very similar, and does not venture far from land.

The South Asian river dolphin, found in the Ganges and Indus rivers of India and Pakistan, is endangered due to commercial usage, human development, industrial pollution, and river damming, which fractures their populations and isolates small gene pools.

The baiji, a river dolphin formerly found on the heavily populated Yangtze River in China, was declared extinct in 2006. The last confirmed sighting was in 2004, and a long expedition to find more in 2006 was unable to turn up a single dolphin. If they truly are gone, it is the first recorded extinction of a cetacean directly due to human influence, though of course we have come very close to eliminating several others in the past.

As recently as 1950 there were 6000 baiji on the Yangtze River, but increased industrialization and growing human cities, along with fishing and pollution, reduced their numbers to only a few hundred by 1970. By 1998 only seven were found in a survey. However, a Chinese man in 2007 filmed what may have been a baiji in the river, giving hope that the animal may still live. Yet even if it does, there is essentially zero hope for its future. A special aquarium was once set up to help the species survive, but most of the baiji held there died within a year, and the last passed away in 2002.

With humans using rivers so heavily, for fishing, for transportation, for electricity, and sadly sometimes for waste disposal, the future of the river dolphins remains entirely uncertain.

4.1f – The Fin Whale

The greyhound of the sea. (Photo by Lori Mazzuca)

The last baleen whale we will examine in depth, the fin whale is actually the second-longest of all whales, growing about 85 feet long, though it does not weigh as much as the right whales. Known also as the finback whale and the razorback whale, the fin whale is narrower than most large whales. This narrow profile gives the fin whale exceptional speed, and it has been called the greyhound of the sea.

Indeed the fin whale is built for speed, or at least as much so as something so big can manage. Its head is pointed for cutting through the water, its fins are small and streamlined, and its mouth is smaller than the mouths of other whales because it has expandable pleats in the bottom that allow more food to enter than would appear possible at first glance, without sacrificing its long, narrow shape. The fin whale can maintain speeds of up to 23 miles per hour.

Fin whales differ from the other baleen whales in other ways as well. Most whales tend toward solitude except for occasional small groups for feeding. The fin whale will often live in groups of up to ten individuals, and when feeding they can gather in groups of up to a hundred.

Oddly enough, the fin whale is also the only whale that is not symmetrical. A symmetrical animal is one that has the same natural appearance on the right side of its body as on the left. Humans, for example, are symmetrical, as are dogs, cats, and just about every mammal. But not the fin whale. Every single fin whale is born with a large white patch on the lower right side of its jaw, with no corresponding patch on the left side. Why is this so? We have absolutely no idea, and the whales won’t tell us.

The fin whale is considered endangered, though to be honest we do not really know for certain how many are out there, how many there were before, and how well they have recovered since the end of large scale whaling, though they do appear to be recovering better than some whales. In very broad terms, we can say that there were once somewhere around half a million fin whales in the world’s oceans, and that we probably killed about 90 percent of them. Those 50,000 or so remaining whales have since recovered to about 100,000, but all of these numbers are relatively rough estimates. You might think that 100,000 is a large number to be on the endangered list, and it is, but the point is that this is still only 20 percent of its previous natural level.

However, if you do feel their population appears to be rather too large for endangerment, Japan and Iceland agree with you. Despite a prohibition on hunting fin whales by the International Whaling Commission, both Japan and Iceland have begun hunting fin whales once again. To date they have kept their harvests relatively small.

Fin whale distribution.

4.1d – The Right Whales

Friendly, buoyant, and quite possibly ancient. (Photo by the NOAA)

The right whales, as opposed to the wrong whales, are a family of four different odd-looking whale species that are interesting for a number of reasons. The four species are the North Atlantic right whale, the North Pacific right whale, the southern right whale, and the bowhead whale, which is the only whale to live exclusively in Arctic waters.

Right whales are big, but shaped differently than most other whales. They have a very broad back, and do not have a dorsal fin, which is the fin that sticks out of a cetacean’s back. A right whale’s head is covered with rough patches of skin called callosities, which is a fantastic word. These patch patterns can help researchers identify individuals. Delightfully enough, these white, rough patches of skin are actually colonies of small crustaceans known as whale lice, and each whale can have tens of thousands of them in unique, unchanging patters on their skin. Right whales also have broad, curved mouths that give them a sort of big, frowny look, but far from being depressed they are actually very friendly. In fact, they are too friendly for their own good.

The reason they are called right whales is because whale hunters believed for some time that they were the “right” whales to hunt. This was for several reasons. First, right whales are less dense than other whales, with a higher percentage of blubber in their bodies, and consequently they are the only whale that floats when it dies, making it easier to harvest after a kill. Second, right whales often swim near shore, making them easier to find. And third, right whales are so friendly that they often swim right up to ships to say hello, which as you might imagine made them popular among hunters.

This propensity to get snuggly with ships harms the whale in other ways even today, when hunting is restricted. Right whales are occasionally struck by ships, sometimes damaging the ship or killing the whale. For this reason many ships face speed restrictions when going through known right whale areas, particularly when right whale calves are learning the ropes.

An interesting thing about right whales is the fact that no one knows how long they live naturally. It was once assumed that they had lifespans similar to other large whales, which is to say, about 60 to 80 years (though even that is a guess in most cases because it is hard to watch a single individual whale for that amount of time).

This assumption was potentially shattered with an influx of certain evidence. Some bowhead whales, including one killed as late as 2007, had fragments of spear points from the 1800s in their skin. This prompted a study that used a female bowhead whale’s eye as a means of determining her age. The researchers came to the rather astonishing conclusion that their test whale was 211 years old.

The results are not conclusive, but there is a possibility that right whales can live 200 years or more, and we have no real idea what their upper old age limit might be since they are so difficult to study as individuals in the wild. There may be lonely giants swimming the oceans today that were young when Napoleon conquered Europe. It is a humbling thought.

As with the other large whales, the right whales were once widely hunted, and some may never recover. Both the North Atlantic right whale (about 400 remaining) and the North Pacific right whale (about 200 remaining) are endangered, and the latter is the most endangered large whale in the world. The southern right whale (12,000) and the bowhead whale (25,000) are in slightly better shape. The bowhead whale has the advantage of a very northerly habitat, and it is also able to hide beneath the Arctic ice when it feels threatened, holding its breath for up to 40 minutes.

4.1b – The Blue Whale

The one, the only, the mind-boggling, scale-tipping biggest animal on Earth. (Photo by the NOAA)

When it comes to whales, where else could we start but here? The blue whale is an utterly wonderful animal that we in our foolish greed very nearly wiped from the face of the planet. For some tragic statistics and some remarkable measurements, read on.

The blue whale is not only the largest animal in the world, it is so far as we know the largest animal to have ever existed, greater even than the biggest of the dinosaurs. Not only that, but it’s so enormous that the second-longest and second-heaviest whales are left in the dust. Just how big is it? A blue whale can measure approximately 100 feet long (25 feet longer than #2, the fin whale) and weigh as many as 180 metric tons, or 400,000 lbs (180,000 more than #2, the bowhead whale). Even a newborn blue whale calf weighs as much as a fully grown hippopotamus. That is a lot of animal.

With its long, impressive shape and blue-grey colouration, the blue whale is highly recognizable. It feeds primarily on krill, a tiny  shrimp-like animal found in enormous numbers throughout the ocean, each measuring less than an inch in size. It filters this food out of water using 300 separate metre-long baleen plates in its mouth.

Speaking of its mouth, a fully grown blue whale can hold up to 90 metric tons of food and water in its mouth at a time. However, its throat is shaped so that it can swallow nothing larger than a beach ball, likely to prevent it from trying to swallow anything dangerously large. In order to feed its prodigious appetite, a blue whale can eat as many as 40 million krill per day, which adds up to about 8000 lbs of food. A blue whale calf will drink up to 400 litres of milk from its mother per day, and add 200 lbs of weight every 24 hours. They are big. They are bigger than big.

And really, everything about them is big. A blue whale’s tongue is absolutely enormous, weighing about 6000 lbs. Its heart weighs as much as an entire grizzly bear.

When feeding on krill or simply travelling, a blue whale can spend 10 to 20 minutes underwater with its breath held before surfacing again. The stream you can see coming up from its blowhole when it surfaces is not an ejection of water as is commonly thought. It is the animal’s breath, turned into water vapour and steam as it leaves the hot body and enters the cool ocean air.

A blue whale ejects air / water vapour several metres into the air every time it surfaces. (Photo by the NOAA)

Blue whales do not properly sing like some other whales, but they do make loud vocalizations that can last up to 30 seconds. The purpose of these sounds is not known, but it may be a way for the whales to let other members of the species know where they are. Blue whales are gentle creatures and always get along when they happen to meet up.

Unfortunately, that doesn’t happen as often as it used to. Imagine, if you will — once upon a time, blue whales were found in large numbers throughout the world’s pristine oceans, not just in their thousands but in their hundreds of thousands. They swam and fed and called back and forth to one another from one side of the world to the other. Even when the age of whale hunting began, the blue whales were too large to hunt. Their only natural predator was the killer whale, and even that fearsome hunter would usually fail against such massive prey.

But things changed. In the late 1800s, whaling technology advanced to a point where blue whales could be killed by men on fortified boats with special harpoons. Between 1880 and 1970, when protective legislation came into place and the Soviet Union ceased illegal whaling, mankind killed approximately 375,000 of these enormous, gentle creatures, and only a few thousand were left in all the world’s oceans — less than one percent of their original numbers. Those few blue whales remaining face ocean pollution that accumulates in their bodies through their food.

They have not yet recovered, and are still an endangered species that numbers somewhere between 5000 and 12,000 individuals. Where once the oceans teemed with gigantic, awe-inspiring blue whales, now there are only a comparative handful scattered throughout the world. And despite the fact that it is so large, and despite the fact that we nearly destroyed it, we still don’t really know all that much about them.

How could that be? Serious studies of blue whales didn’t begin until after the whaling had stopped, and even then it is a difficult business. You may think that such a large creature would be easy to observe, but it is not so. For one thing, you cannot put a blue whale in captivity and then study it. Even dead blue whales could not be properly studied, as they had to be cut into pieces before they could be moved anywhere.

And where would you find a blue whale to study? There are so few, and the oceans are so large. We know a little about what they do near the shore, but very little about their behaviour in the open water — where they go, what they do, how they live. To understand this curious hole in our knowledge base, you must first understand how big the oceans really are. There is much more ocean than there is land, and the ocean has depth that the land cannot match.

Imagine for example that there was only one person in the entire United States of America. Only one. This person rides a bicycle around the country, able to go wherever she wanted, not tied to roads or to cities or to anything. You, a researcher, are sent to study this person, but first must find her. In all of the country, where would you look? How would you find her? Once you do find her, you must study her on foot while she is able to ride away on her bike, faster than you can watch. Also, the bike is magical and can fly off hundreds of feet into the sky for twenty minutes at at time, turn invisible, and come back down wherever it likes. This is what it’s like to study the blue whale in the open ocean.

Gargantuan and mysterious, the blue whale is found in every part of the ocean except for the high Arctic waters and some narrow seas. They migrate in search of the best feeding grounds, and are always a magnificent sight to behold for those lucky enough to spot one. We can only hope that they will continue to roam the vast waters for many generations to come.