The Zanzibar Leopard: A Lesson in Island Dwarfism....and Extinction

Very few people have heard of the Zanzibar leopard, unless of course you are a person from Zanzibar, an island ecologist interested in insular leopard populations, or you are another Zanzibar leopard.  (Which might be problematic, being another Zanzibar leopard, but we'll get to that later.)  In the meantime, let's look at what makes the Zanzibar leopard so special: its size.

When a population of animals becomes trapped on an island, they have to adapt or die: it's just that simple.  While many populations simply succumb to death, other populations of animals can sometimes shrink over the course of many generations, eventually becoming dwarfs of their former selves.  It's called island dwarfism, and it's happened many, many times throughout the history of life: the dwarf dinosaurs of Hațeg; the Channel Islands pygmy mammoth and the Channel Islands fox; the Cozumel Island fox and the Cozumel Island raccoon; and many, many others.  The subject of today's post is (you guessed it!) the Zanzibar leopard and, as you also might have already guessed, this particular leopard is an island dwarf!  

The leopard (Panthera pardus) is simply a fascinating animal.  Able to drag prey weighing more than three times its own weight in some cases, this mid-sized feline is the midnight stalker of the African savannah.  An occasional man-eater, there are numerous sub-species of the leopard, although no one can quite agree just how many there actually are.  While some people claim that there are just a few sub-species, others have claimed that there are around thirty!  However, most scientists agree that, at least for now, there are only eight or nine sub-species.  For regular readers of the blog, you've actually met a few of these sub-species already!  Probably the most famous, the African leopard (P. pardus pardus), was featured in a post about a year ago, entitled "Predators of Baby Leopards: You Might Be Surprised," in which we talked about....well, just read the post for yourself!  More recently, we met the Amur leopard (P. p. orientalis) in a post entitled "An Amur Leopard Upchucks."  I'm pretty sure you can figure out what that post is about all on your own.

There is some debate about whether the Zanzibar leopard is simply a separate population of the African leopard (P. p. pardus), or whether it is a distinct population defined by genetics.  When it is defined as a separate sub-species, the Zanzibar leopard has the scientific name of Panthera pardus adersi.  We'll talk more about this genetic confusion later: but that's enough about the genetics,  let's get to the interesting stuff!

Scientists think that the Zanzibar leopard has been isolated from the rest of the African leopard population on the mainland since the end of the last Ice Age, at which point global sea levels would have risen, cutting off the two main islands of the Zanzibar Archipelago, Unguja and Pemba, from the mainland.  Unguja, which is informally known as Zanzibar, is where the Zanzibar leopard can be found: at least, it used to be found there.

Remember when we were talking about how scientists can't really agree on whether the Zanzibar leopard is a distinct sub-species or not?  Well, their research is not aided by the fact that the Zanzibar leopard seems to be extinct.  Following the Zanzibar revolution in 1964, the government began a program to eradicate the Zanzibar leopard, both to stop apparent live-stock killings attributed to the cat, as well as to eliminate the leopard as an apparent source of witchcraft.  Research conducted in 1996 indicated that the leopard still survived on the island, but more recent research in 2002 has found no sign of the leopard.

Adapt or die: that's the mantra of the island animal.  When you throw humans into the mix, unfortunately its the second option that seems to occur most often.  Thousands of island animals have been exterminated by humans as their habitat is destroyed in the name of progress.  With nowhere else to go, they die out, leaving behind a legacy of destruction.

This was the birthday post of Ted Neher! Happy birthday, Grandpa! If you have a birthday coming up, just email me the date at cuyvaldar123946@gmail.com with the date and your favorite animals, and I will do my best to get a post in! And if you like what you are reading, please feel free to follow us here or via Facebook!

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Island Hop (to the tune of "Thrift Shop")

Here we have the fourth song in the series, "Island Hop," to the tune of the very popular "Thrift Shop" by Macklemore.  Below is a link to the parody:

Here are the lyrics to the song:


Hey, Macklemore!  Can we go island hopping?

In-su-lar-ized...[x7]

Island, bio, geogra, phy... [x9]

[Hook:]
Australia and Tobag-
-o, Cross them both off my docket
Take a look at some of these animals close-up
Kakapo, Penguins and the Possum

[Verse 1:]
Nah, walk up to the map like, "What up with all these chunks of rock
Out in the deep blue sea, barely staying on top."
Ice in Antarctica, it's so dang frosty
That penguins like, "It's cold enough here to completely freeze a donkey."
Floatin' in, water's deep, I can see a dorsal fin,
Dressed for adventure, 'cept for one fact, I'm completely clean
Hoppin' off, walkin' round, I can really barely see
Probably should remember, there are some big animals here that need to eat-
(Hissssss)
But shoot, it's a Komodo Dragon! (Dang it)
Runnin' round, leap and bound, my death I hope to circumvent
Don't want to be a has been, someone needs to find my next of kin
But now I got a game plan
Run up to that tree and climb and
Wait up there 'til someone comes along and helps me down, really, it's a cinch
Next I'm off to Baffin Isle., turn the clock back awhile,
No for real - ask your grandpa - once the great auk here was found? (That's right)
Polar bears, arctic terns, and some things with flippers
And even more fossils if you just get diggin'
To avoid getting bored, let's head to the opposite seaboard
To the Channel Islands, much of which are rarely explored
Hello, say hello, to the Island Tree mallow,
The Channel Island fox and the introduced Catalina Island buffalo
Unfortunately, its now extinct, but at one point, there arose,
A 6-foot tall mammoth that would barely reach up to your nose

[Hook]
Australia and Tobag-
-o, Cross them both off my docket
Take a look at some of these animals close-up
Kakapo, Penguins and the Possum

[Hook]
Australia and Tobag-
-o, Cross them both off my docket
Take a look at some of these animals close-up
Kakapo, Penguins and the Possum

[Verse 2:]
What you know about island dwarfism?
What you know about the Cozumel Island fox, then?
I'm digging, I'm digging, I just can't find that page
An adult Cozumel's as big as a red one's pup
Thank your granddad for helping to slow the extinction and to-avert
'Cause right now we might still have the living thing
I'm in New Zealand, you can find me in (Wellington)
I'm not, I'm not sick of searchin' in that region (Wellington)
For the kea, the kiwi, the korora, the weka,
There ain't no native mammals in New Zealand, cept for bats, and of course whales and dolphins
Other marine ones like the seals and the sea lions
I hit the button and then through time we go flyin'
They be like, "Here we are at Hațeg - yo, let's check out the sites."
I'm like, "Whoa - that's Balaur and Hatzegopteryx."
Despite the transition, it's time to finish our mission
Magyarosaurus and Struthiosaurus - neither of which
Are very tall at all, they have both been shrimped
I call that island dwarfism at its most intenseness
That's not all that's here, though
Telmatosaurus, Bradycneme, and of course the Rhabdodon, or Rhabdodon't
But separating us from the mainland, no continental slope
In the future this place, separated from Romania it won't
Man it surely won't

(Hațeg...island dwarf...yeah!)

[Hook]
Australia and Tobag-
-o, Cross them both off my docket
Take a look at some of these animals close-up
Kakapo, Penguins and the Possum

[Bridge: x2]
Take the mainland and an island and juxtapose
It's quite incredible
They're surrounded by a moat
Which helps animals change their genetic code

[Hook]
Australia and Tobag-
-o, Cross them both off my docket
Take a look at some of these animals close-up
Kakapo, Penguins and the Possum

Is that your grandma's Balearic Islands cave goat?

Are you diggin' the songs?  Well, then check out our playlist below!

CLICK HERE TO BE DIRECTED TO A FUN-FILLED PLAYLIST OF AMAZING SONGS.

Shrinky Dink: The Channel Island Fox and The Island Effect

If you (as a species) get trapped on an island, there is really one of three things that can happen.  The first thing, which seems to be like it would be the most common of the three things, is that you and your species would go extinct on the island.  Perhaps your species still survives on the mainland, but the island group has died off.  The second, and second most likely to happen (in my opinion) is you and your species, over many generations, shrink, to match the food supply.  If there is a limited supply of food, then the smallest of your species, not the largest, are much more likely to survive.  And the third happenstance is that you and your species grow in size over many generations.  Say you and your species are rats.  On the mainland, you are preyed upon by dogs, foxes, coyotes, cats, and the like.  When you and other of your rat buddies became trapped on the island, there was an abundnace of food there, but no predators to prevent you from growing bigger.  So grow you did.  We will talk about a very interesting occurrence of this later on. This shrinking and growing, called "Foster's Rule," is often simply known as "The Island Rule."

For now, however, we are going to focus on the more common of the two, and the more interesting (both in my opinion); island dwarfism.  This has occurred many, many times throughout history, and even to humans!  However, today we are going to look at one particular occurrence of this dwarfism.  The Channel Island fox of the Channel Islands off of the coast of California.

Scientists believed that the ancestors of these foxes "rafted" to the northernmost islands in the island chain sometime between 10,400 and 16,00 years ago.  These ancestors would have been the gray fox, very similar to the ones we see today.  The foxes rafted over during the last Ice Age.  This would have dramatically lowered the sea levels, and much of the water that is in today's oceans would be locked away in the ice caps at the poles, or in glaciers.

As you can see in the map below, the four islands of San Miguel, Santa Rosa, Santa Cruz, and Anacapa are all located with only shallow water separating them.  During the Ice Age, with the lower sea levels, these four islands were all one island, called Santa Rosae.  Also at this time, the distance from the mainland to the "mega-island" would be much smaller, making the crossing for these gray foxes much easier.  It has been theorized that Native Americans then brought the fox to the four southern islands, as hunting dogs, or perhaps even pets. 

The mainland gray fox.  Photo credit Zack Neher, taken at Brookgreen Gardens in South Carolina.

Today, the fox only lives on six of the eight islands, with distinct sub-species on each island.  The fox still inhabits the islands of San Miguel, Santa Rosa, Santa Cruz, San Nicolas, San Clemente, and Santa Catalina (often simply called Catalina Island), and is absent from the islands of Anacapa and Santa Barbara.  While Santa Barbara is too small to support the food needs of the fox, Anacapa has no consistent source of fresh water.  The fox is the largest on Catalina, and the smallest on Santa Cruz.  The foxes on the southern three islands all have become separate at different dates, with the foxes of San Clemente estimated as being the oldest (becoming isolated between 3,400 and 4,300 years ago).  The San Nicolas fox is next, at around 2,200 years ago.  Finally, the foxes of Catalina Island, between 800 and 3,800 years ago.

Even smaller than the mainland kit and swift foxes, the Channel Island is the smallest of all of North America's foxes.  Like many island animals, the Channel Island fox is labeled as "Critically Endangered" by the IUCN, as they don't have much territory to spread into when humans influence them.  One influence was indirect, but still devastating for the foxes.  Prior to the 1990s, the golden eagle was a rare visitor to these islands.  The bald eagle, already well established in the area, was apparently a large deterrent for the golden eagle, preventing them from settling on the island.  DDT helped to eradicate the bald eagle on the Channel Islands, and with very few bald eagles in the area, the golden eagle moved into the gap: nature abhors a vacuum!

Anyways, the golden eagle, unlike the bald eagle (who is primarily piscivorous) would, and did, hunt the Channel Island foxes; at four times the foxes size, they were most definitely a force to be reckoned with.  That, coupled with diseases brought over from the mainland by domestic dogs, such as canine distemper, have also wreaked havoc upon the fox populations.  Conservationists are currently working on a solution, and tracking the foxes with radio collars seems to be helping them learn more about the foxes, in an attempt to prepare for the future. 

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The Fauna of South Carolina: Cetaceans, Foxes and Otters

Here is the second in the "Fauna of South Carolina series."  Today, we are going to take a brief look at some of the cetaceans, foxes and otters that we saw while we were down there, either in the wild or in zoos.  Let's start with the otters.

River Otters ("Least Concern" by the IUCN) at Brookgreen Gardens

We saw both the otters and the foxes at Brookgreen Gardens, at their Lowcountry Zoo.  Not quite as cool as the foxes in my opinion were the river otters.  They were definitely really cool, as they were running around and playing a great deal, and we had a great view of them.  I'm not sure if I have ever seen otters playing so much, and seen it so well.  It was definitely quite a treat!  The range of the river otter is slightly weird; encompassing Oregon, Washington, and parts of California,and then extending throughout most of Alaska and Canada, and then coming down along the east coast of the United States, down to Florida, Mississippi, Alabama and Louisiana.

Gray Fox in tree

Prior to that, we had visited the fox exhibit.  We were looking for red fox and gray fox.  If I recall correctly (which I often don't), we were having trouble seeing the gray foxes, when I noticed something moving in one of the trees.  It was the gray fox!  I had no idea that foxes climb trees!  In fact, other than the raccoon dog found in Asia, I believe not many other canids in fact do climb. 

Gray fox in tree

Gray fox in tree

Gray fox in tree

 The gray fox, like the river otter, is labeled "Least Concern" by the IUCN.  Its range stretches from most of North America, down through Mexico, Central America, and into bits of South America.  The Channel Island Fox (a very interesting animal that we will by all means talk about at some point soon) is almost certainly descended from gray fox on the mainland. 

Instead of doing the cetaceans like we previously planned today, I think we should do them some other time.  See you later!

This post is part of "The Fauna of South Carolina" series.  For the rest of the posts in this series, click HERE.

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