Pangolin (family Manidae)

I find it quite shocking that I have not written about pangolins yet. These guys are some of my all-time favourite mammals, and yet I’ve ignored them for nearly four years of blogging and over four hundred posts. I know I’ve considered writing about them, but perhaps the time was never quite right. Well, today is the big day for pangolins, because these amazing animals are going to get their very own blog post!

There are eight species of pangolins, all of which belong to the family Manidae. Pangolins can be found in Africa, India and southeast Asia. All species live in tropical areas, though they differe in their lifestyle choices, with some being arboreal and some preferring to live on the ground. Most pangolins are nocturnal, with only one species, the long-tailed pangolin, being active during the daytime.

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A map showing the distribution of pangolins in Africa and Asia. Image credit: Craig Pemberton via Wikipedia

Pangolins vary in size depending on the species, ranging from 30 to 100 cm long. The most notable feature of pangolins is their overlapping scales that look extremely out of place on a mammal. These scales are made of keratin, and harden as the animal matures. They may look funny, but the scales provide pangolins with an excellent mode of defence. When a pangolin feels threatened, it curls up into a ball, tucking its head under its tail, leaving the predator with only a hard, spiky ball to look at.

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This pangolin seems to have stumped these lions with his ‘curl-in-a-ball’ defence. Image credit: Sandip Kumar via Wikipedia

Pangolins are at home in a number of different environments. They happily climb trees, with some species of arboreal pangolin having prehensile tails that they can use while climbing. Ground dwelling pangolins dig burrows, which can reach depths of three and a half meters. Some species of pangolins will walk with their front claws folded under their feet, and others will sometimes rear up and perform some behaviours bi-pedally, even walking on two legs for small periods. But climbing, digging and walking aren’t the only things pangolins can do; they can also swim quite well. That’s pretty impressive for such awkward looking animals.

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A Sunda pangolin showing off its climbing skills. Image credit: Piekfrosch via Wikipedia

So what do these strange and wonderful animals eat? Pangolins like to feast on tasty and nutritious insects. They use their strong claws to dig up bug nests in trees and on the ground, and then stick out their tongues to gobble them up. Pangolins have incredibly long tongues, which are coated in saliva from glands in the animals’ chests, making them extra sticky, and thus the perfect insect grabbers. Though insects are tasty, they are small, so pangolins have to eat a lot of them. They eat between 140 to 200 g of food a day, and are quite picky, generally eating only one or two species of insect.

Another weird thing about pangolins: they don’t have teeth. They get around this by having a very muscular chamber in their stomachs, complete with spikes that help grind up food. Pangolins will also swallow stones or pebbles that assist in grinding up any food they eat.

Pangolins live solitary lives, coming together only to reproduce. There is no set mating seasons, and pangolins usually mate once a year. Pangolins are a little backwards when it comes to mating — instead of males heading out to find mates, females are lured to spots marked by male pangolin urine or dung. There is some competition over females; when this occurs male pangolins establish dominance by swinging their tails at one another.

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A little baby pangolin riding on its mama’s tail. Image source

Gestation in pangolins ranges from 70 to 140 days. Litter size depends on the species, and can be one to three baby pangolins. When they are born, the scales of young pangolins are soft (imagine giving birth to a baby armoured with spiky scales!), and these harden after several days. While the scales are still soft, mother pangolins are very protective of their young, wrapping themselves around their babies if they feel threatened. After a few weeks the young pangolins ride around on their mother’s tails, and they are weaned at around three months of age. They become sexually mature at two years of age.

There is, of course, a sad side to the pangolin story. They are hunted for their meat and their scales, as pangolin meat is considered a delicacy in many areas, and their scales are thought to have medicinal qualities. Pangolins have the upsetting title of being the Most Illegally Trafficked Animal in the world. All pangolin species are currently threatened, and two are listed as critically endangered. Though they are protected species, illegal trafficking remains a serious threat to the pangolin population. On that sad note, I’ll leave you with a cute drawing of a baby pangolin.

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A quick little sketch I made of a pangolin. So many scales to draw! 

Cover image source

Kiwi (genus Apteryx)

There is no more hilarious bird than the kiwi. Its funny body shape, strange beak, and bizarre biology make it a jolly combination of oddness. What a great bird!

There are actually five living species of kiwi, all of which are found in New Zealand. They are ratites, an order of flightless birds that includes giants like ostriches and emus. Unsurprisingly, kiwis spend their time on the ground, constructing burrows from a variety of materials in their habitats. They are found in numerous areas, including forests, scrublands and grasslands.

Kiwis have wings, they are just so small that they can’t be seen under the birds’ feathers. The smallest species of kiwi is the little spotted kiwi, at 25 cm in height, and 1.3 kg in weight. The largest is the great spotted kiwi, which grows to a height of 45 cm, and weighs 3.3 kg. Kiwis are covered in soft feathers, as they do not require hardened flight feathers. As another adaptation to their ground-dwelling lifestyle, kiwis have solid bones filled with marrow, unlike the hollow bones of other birds. Who needs to be lightweight when all you do is stumble around the forest floor?

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I can’t help but giggle when I look at a kiwi. Just look how weird they are! Image source: http://www.liveanimalslist.com/birds/kiwis.php

For the most part kiwis are nocturnal birds, though it seems that at least some of this nocturnality is a result of introduced predators. In areas where there are no predators, kiwis tend to venture around during the day. Still, kiwis have adapted quite well to the darkness. They have poor eyesight, but an exceptional sense of smell. A feature unique to kiwis is their nostril placement: while all other birds have their nostrils located at the base of the bill, kiwis have theirs at the tip. This allows kiwis to find yummy insects and worms with ease, even if they are underground.

Kiwis form strong monogamous pairs, and tend to stay together for life. Males court females through a variety of techniques, including grunts, leaps, and snorts. Kiwis produce massive eggs, and in fact have the biggest egg to body size ratio of any bird species. A kiwi egg can weigh a quarter of the weight of the female carrying it. While the egg is developing, the female kiwi must increase her food intake, eating three times as much as usual. By the time the egg is ready to be laid, it has grown so large that there is no room left in the female’s stomach, and thus she cannot eat until the egg is laid.

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A diagram showing the relative size of a female kiwi and her egg. Image source: Wikipedia

Largely due to introduced mammalian predators, such as stoats, cats, and dogs, all species of kiwi have experienced population declines. Two of the five species are listed as vulnerable, one is endangered, and one is critically endangered. It is estimated that only 5% of kiwi chicks survive to adulthood. Conservation programs, which have focused largely on providing predator-free sanctuaries for kiwis, have been reasonably successful. I am hopeful these guys will be around for a while to come, because they are just too silly to lose.

Cover image source: http://phys.org/news/2015-07-kiwi-bird-genome-sequenced.html

Kakapo (Strigops habroptilus)

For some reason I don’t seem to write about parrots very often on this blog. I’ve only written about the Red and Green Macaw, and other than that have ignored this group of birds completely. I think it’s because parrots are, in my mind, domesticated birds. But there are many species of parrot in the wild, and today’s animal is one of those.

The kakapo originally ranged all over New Zealand, but today no longer survives there. The introduction of predators by European colonists wiped out all kakapos on the main islands. Today wild populations of kakapos only exist on three predator free islands: Codfish, Maud, and Little Barrier island.

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A nice shot of a kakapo’s face – note the ‘whiskers’ around the beak. Image credit: Brent Barrett via Wikipedia

Kakapos are flightless parrots, which is the main reason why they were such easy pickings for the introduced predators. They are very good climbers, however, and can jump from the tops of trees, using their small wings as ‘parachutes’. They make up for their flightlessness by being quite large — they are, in fact, the largest species of parrot. Kakapos can reach lengths of 64 cm, and weigh up to 4 kg. They are covered in yellow-green feathers that help them blend into local vegetation.

Kakapos are different from other parrots in many ways. For one thing, kakapos are nocturnal. They have a few adaptations to help them make their way around in the dark. First, kakapos have a bunch of small feathers that surround its beak, acting as whiskers so the kakapos can find their way around the forest floor. They also have an excellent sense of smell, another unusual trait for a parrot.

The breeding system in kakapos is also very unusual, and it is the only flightless bird in the world to use a lek breeding system. Male kakapos gather on hills and ridges, fighting with one another for the best spots. Once a male has secured his display spot, he will dig depressions into the ground at different locations on the hill. These bowls help amplify the males’ mating calls, which can be heard up to five kilometres away, if the wind is right. Male kakapos are meticulous about keeping their bowls clean, and will call from different bowls to send their calls in as many directions as possible. It sounds like a lot of hard work, and it is. Males call for about eight hours a night, for a duration of three or four months. They can lose up to half their body weight from the strain.

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A kakapo using its feathers for camouflage. Image source: Wikipedia

A female kakapo lays one to two eggs, on the ground under cover or in hollows. She incubates them for a month, but must get up and feed during the night, leaving the scrumptious eggs vulnerable to cold and predation. If the chicks make it to hatching, the female will feed them until they are three months old, at which point the chicks fledge and start to gain some independence. They continue to hang around their mother until about six months of age, at which point they leave for good.

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Baby kakapos. Somewhat adorable, and somewhat hideous. Image source:

Kakapos are teetering on the edge of extinction — today only 126 kakapos exist in the wild. Thanks to human introduced mammalian predators, these birds were nearly completely wiped out. Extensive conservation efforts mean they are still around, but keeping the species going has been extremely difficult.

There are a number of reasons for this, one being that mammals are quite tenacious, and keep colonizing islands set aside for kakapo habitats. Another is the breeding habits of kakapos; these birds have and extremely long lifespan (an average of 95 years and a maximum of 120!!), and thus do not breed every year. In fact, kakapos only breed in years when fruit trees produce an abundance of food, which occurs every three to five years.

Conservationists were able to increase kakapos’ breeding rates by providing them with supplementary food, but ran into problems with this strategy. You see, female kakapos are able to control the sex of their eggs, giving birth to more males (which are larger) when fed a protein rich diet. For conservation purposes, female birds are much more valuable than males, and so scientists have to give the birds enough food to induce a breeding season, but not enough so that most of the chicks are male. They’re starting to get the formula right, and the kakapo population has been increasing steadily (albeit slowly) for the last few years. Hopefully this trend will continue!

Cover image source: http://www.wired.com/2014/03/creature-feature-10-fun-facts-kakapo/

Mary River Turtle (Elusor macrurus)

As this blog has clearly demonstrated, there are some very odd looking animals out there. As far as turtles go though, I think the Mary River turtle takes first prize. This turtle actually looks like one of the Koopa Kids from the Super Mario games. Here’s a picture just in case you have no idea who the Koopa Kids are:

On the left, Iggy Koopa, and on the right, a Mary River turtle.  Photo credit: Chris Van Wyk

On the left, Iggy Koopa, and on the right, a Mary River turtle.
Photo credit: Chris Van Wyk

Mary River turtles are named after the river they inhabit: the Mary River in Queensland, Australia. This is the only place that these turtles inhabit. The Mary River turtle prefers areas of the Mary river that are fast-flowing, with a steady supply of oxygen. They are partial to areas with some kind of shelter, such as underwater logs or rock crevices. During flooding, Mary River turtles move upstream, heading to eddies or backwaters where the flow isn’t quite as fast. Once water speeds return to normal the turtles return to their normal habitats. Mary River turtles are quite unique; they are placed in their own genus, and are one of the only remaining turtles from a very ancient evolutionary lineage.

These turtles are quite big, having a shell size of over 35 cm. They are usually dark brown or black, with a grey underbelly. They have very long tails compared to other turtles, with tail length exceeding 7 cm. One notable feature is Mary River turtles’ barbed chins, which makes them look quite tough. To add to their punk-rock look, Mary River turtles sometimes have algae growing on their heads, presumably to assist with camouflage.

Another interesting feature of Mary River turtles is the bursae located on their cloacae. The cloaca is the turtle’s way of expelling urine, faces, and reproducing. The bursae located on the Mary River turtle’s cloaca act like gills, allowing the turtle to absorb oxygen from the water. They can’t get all their oxygen this way, however, and so still surface to breathe with their lungs every once in a while.

Mary River turtles have very large back legs and streamlined shells, making them exceptionally good swimmers.  Image source: https://www.pinterest.com/pin/235031674275220025/

Mary River turtles have very large back legs and streamlined shells, making them exceptionally good swimmers.
Image source: https://www.pinterest.com/pin/235031674275220025/

Mary River turtles nest on sandy banks of the Mary River. Females are faithful to particular banks, and many turtles will use the same nesting site. One bank had evidence that over 100 females used the site to lay their eggs. Females lay 12-25 eggs per season, and usually lay from October to November. Once the eggs have hatched, the young turtles have a long road ahead of them: it takes around 25 years for a Mary River turtle to reach maturity.

Until the 1990s, the Mary river turtle was not actually classified as a species. It was being sold in the pet trade, under the Common Saw-shelled turtle. Though biologists were curious about the strange turtle, they could not formally describe it, because the pet traders would not reveal the source of the turtles. Legal trade in the species was banned in 1974, but scientists still could not locate the habitat of the Mary River turtle. It wasn’t until 1994 that adult specimens were found in the wild and the species was named and classified.

All and all, I think I have to declare the Mary River turtle one of my favourite turtle species. It’s just weird enough, with an interesting history and the right amount of silliness in its appearance. It’s my kind of turtle, that’s for sure!

Cover image credit: Chris Van Wyk

Sturgeon (family Acipenseridae)

I remember as a child being very impressed by the sturgeons at the Vancouver Aquarium. You see, they were bigger than all the other fish in the tank. Which to a kid, means they are the most important fish in the tank, and really the only ones worth looking at. Today, while pondering what animal to blog about, the memory of those sturgeons came to me, and I realized I know very little about them. So I looked them up, and have decided to share what I learned with you, my dearest readers. 

Sturgeons are very ancient fish — after their first appearance in the Cretaceous period, they have changed very little. They are part of the family Acipenseridae, which contains around 25 species. Accurate classification of sturgeon species is difficult due to variations in appearance that can occur between the same species at different ages and in different locations. Another complicating factor is the sturgeon’s ability to hybridize between species of sturgeon. It just makes me glad I’m not a sturgeon taxonomist. 

A beluga sturgeon, the largest species of sturgeon, and one of the largest fishes in the world.  Photo Credit: Tony Gilbert

A beluga sturgeon, the largest species of sturgeon, and one of the largest fish in the world.
Photo Credit: Tony Gilbert

Sturgeons can be found pretty much all over the Northern Hemisphere, from the west coast of North America to the Yangtze river in China. Most species live in fresh water, inhabiting rivers, lakes and estuaries. Some sturgeons spawn in fresh water but move to salt water coastlines for their adult lives, while others spend their entire lives in freshwater, either because they evolved that way, or humans have forced them into that existence. 

I wasn’t wrong to be impressed when I was a kid. Sturgeons can get big. Really big. The beluga sturgeon in the Caspian Sea can reach lengths of 5.5 metres, and weights of 2000 kilograms. Of course, the ones at the aquarium weren’t that big, but they were certainly large enough to make an impression on a young me. Sturgeons have some notable features that make them easily recognizable. They have four barbels on their face, which the sturgeon uses to feel its way around the often muddy waters in which it lives. Another distinct feature of sturgeons is that they have a number of bony plates on their body called scutes, instead of scales. It is thought that the lack of natural sturgeon predators (due to their large size and scutes) and their extremely long lifespan (over a hundred years!) have contributed to the extremely slow evolution of the sturgeon. 

A close up of a sturgeon mouth. They extend their mouth to help them suck up tasty things from the water depths.  Image source: http://www.polycount.com/forum/showthread.php?t=92833

A close up of a sturgeon mouth. They extend their mouth to help them suck up tasty things from the water depths.
Image source: http://www.polycount.com/forum/showthread.php?t=92833

Sturgeons are bottom feeders, and use their barbels to find prey. When prey is found, the sturgeon uses its mouth to suck its meal up. Most sturgeons feed on small prey, like crabs, shells and small fish. They do not have any teeth, so they have to swallow their food whole. Some species can do this to quite large creatures, like whole salmon. You’d have to be pretty large to swallow a salmon whole. It’s a little scary to think about. Have they made a Mega Shark vs Giant Sturgeon movie yet?

Unfortunately for sturgeons, their long lifespan and slow reproductive rate make them particularly vulnerable to overfishing. They are also the source of caviar, which makes fishing sturgeon quite profitable. Caviar, of course, is fish eggs, which means the product is harvested from females with reproductive capabilities, further increasing the stress on sturgeon populations. All of these factors bode poorly for sturgeon conservation, and have made sturgeon the most critically endangered group of species in the world, according to the IUCN. So if you’re going to buy caviar, make sure it’s from a sustainable source! 

Cover image source: http://www.biomar.com/en/BioMar-France/Species-and-products/Sturgeon/