My First Skull

One of the benefits of regular camera trapping trips is that you end up spending a lot of time in the field looking for good camera locations, and as a result you are bound to stumble upon some interesting things.

This skull was found amongst some other bigger bones that was damaged by a fire

When I saw this skull a new world opened up to me. Suddenly I could see myself as an Amateur Skull Collector. This is the first time I've found such an interesting and well preserved skull and as a result I'm very excited about it.

Now, I'm no skull expert and some of my terminology might be wrong, but I hope my general interpretation is correct. Please feel free to correct me in the comments section below.

One of the first thoughts to pop into my mind was: What species could it be?

The business end of the skull, notice the well developed teeth, jaw and nasal opening

The first thing I noticed was the formidable teeth. Clearly this is a coldblooded killer. With large canines to kill with and the rest of the teeth designed to cut through flesh, I knew that I was dealing with a strict carnivore.

The next clue was its size...

This photograph shows the size of the skull which is about 2x5cm

It is a small sturdy scull. The small size narrowed it down considerably. Of all the small carnivores found at Tygerberg, this surely had to be an African Striped Weasel. Fortunately for you, and me, I camera trapped another one of these little weasels just a week before finding the skull.

African Striped Weasel (Slangmuishond - Poecilogale albinucha) camera trapped at Tygerberg Nature Reserve in Cape Town, Western Cape

I took the skull home to try and clean it. I also wanted to examine it in more detail. What truck me was just how tightly the lower jaw slides into the upper jaw. The photograph doesn't do it justice.

Scissor like teeth and cracked "cheekbone" clearly visible

The presence of these little rodent killers in Cape Town is still not know by many people. Recent discoveries of African Striped Weasels in the Cederberg area has filtered through to the biological community, but most of the updated distribution maps I've seen are still reluctant to adjust the distribution all the way down to Cape Town, yet I now have three records, spanning over two years, of African Striped Weasels at Tygerberg Nature Reserve.

Sub-Saharan Africa has a relative shortage of species from the Weasel (Mustelidae) family. One theory is that the Mongoose (Herpestidae) and Genet (Viverridea) families already occupies most of the habitat niches leaving little room for the weasels to claim for their own. Specializing in hunting rodents in their burrows obviously gave this weasel it's edge.

It is also interesting to compare the three terrestrial species of Mustelidea found in South Africa: African Striped Weasel, Striped Polecat and Honey Badger. They have surprisingly many things in common, for instance they all have similar black and white warning colouration, they can secrete a foul smelling substance when threatened, they are also awkward movers that aren't particularly agile or swift, they are all hardy and tough with thick loose fitting skins and (in particular two of the species) have a great knack for digging and are keen underground hunters. In a sense the biggest difference between these species is their size.

The remaining two species of Mustelidea found in this part of the world part of the Otter subfamily, and again we find ourselves dealing with habitat specialists.

The jaw is strikingly compact and powerful, opening up for a surprisingly large gape

Another interesting thing about this weasel is that the tooth at the back of the mouth on the top jaw is turned 90 degrees and creates another cutting surface with the tooth on the lower jaw.

Closeup of the eye socket and top of the upper jaw

The eye-socket isn't encircled by bone, as is the case in most mongooses. Maybe this is as a result of their burrowing lifestyle. They hunt rodents in their burrows and I'm guessing protruding bones around the eye might be a liability. It is said that the African Striped Weasel can turn around in any burrow that is wide enough to allow its head to turn.

You can also see how the roots of some teeth actually protrude through the upper jaw.

They rely heavily on smell to find food, since it is the best way to hunt in the dark tunnels for rodents. It is said that these weasels will pass within 5 cm of a mouse without reacting if it can't smell it.

Skull showing damage that might have been related to the cause of death

So, how did this individual die? Well, the left hand side of the skull clearly shows some damage. Two cracks on the cheekbone and some damage to the cavity at the base of the skull can clearly be observed in the photographs. My guess is that it was killed by a bigger predator. Maybe the fact that I could not find the rest of the skeleton in the area is a clue? Maybe a bird of prey, possibly and owl, caught it and the bird's talons damaged the skull, or maybe it was taken out by one of the Caracal. I'm not sure.

Finding a skull is great and all, but how do you go about cleaning it? Luckily I recalled a recent post by Trailblazer (over here) that got me started. In the end I soaked the skull in roughly 4% Peroxide for about 10 minutes. I then rinsed it well with tap water and left it to dry.

The skull happily bubbling away in a jar full of Peroxide

I then secured the teeth with Superglue. The skull seemed a little brittle and I decided to go with one coating of spray-on Polyurethane to seal it. The end product looks decent enough, although some of the very fine texture is lost by the Polyurethane. I'm also not very fond of the semi-glossy look, but it isn't too bad and might fade a bit over time. I hope the Polyurethane will help to preserve the skull over time. If there are any experts out there with some advice, then please feel free to post a comment below.

The final product

I can't wait to find another skull. I'd love to build up a collection of small mammal skulls. Now if only I can get my hands on a mongoose skull to compare this one with...

Back At The Berg

Yep, I'm back at the Berg, the Tygerberg!

After being away from Tygerberg for more than a year it felt like a good time to get back up there, and the email from the reserve manager asking for help with a tortoise problem was the push I needed :)

First up is some Cape Gerbils. I have developed a fondness for rodents over the years. There is just something about their miniature lives that is wonderful, and they make for surprisingly co-operative camera trapping subjects.

Cape Gerbil (Kaapse Springmuis - Tatera afra) at Tygerberg Nature Reserve

To help things along I decided to put some bait out in an attempt to keep the action in front of the camera for longer. The Birdcam has a strange detection circuit and it is best used on a baited setup. I didn't have any Sunflower seed at hand so, before leaving home, I looked in the kitchen cupboards for something suitable. I went with a mix of Barley and Lentils.

The Afrikaans name "Springmuis" translates to Jump-Mouse

I think the bait did the trick. It was all gone a week later and I got lots of photographs of ransacking rodents facing off over the spoils.

"Back off! This is my lentil" "Grrrr I saw that barley first!"

We are in the last stretch of the warm and dry summer season here in Cape Town and these little critters must have enjoyed this bonanza a great deal.

Are these Cape Gerbils prone to the "Tripod Stance"?

Since the Codger's post about the "tripod stance" (standing on three legs with one paw close to the chest) I've enjoyed keeping an eye open for this stance in all animals from humans to gerbils. (You can read Codger's post over here.) Our one dog uses this posture a lot, especially when smelling strange new smells. Strangely enough it is also her preferred water drinking pose, so some mysteries still remain.

The Birdcam has a manual focus that must be configured when you setup the camera, this results in some areas being very sharp and others being out of focus, so "positioning" the animal becomes more important

I've been wanting to get more colour photographs of the Tygerberg Cape Gerbil colonies because I always felt there was something strange going on, maybe another species or something. This time around I think I've solved the mystery: Colour variation.

Two Cape Gerbils clearly showing the collor variation

The gerbils differ in size as well, I'm guessing they are of different gender and age.

This Cape Gerbil clearly shows a strange white marking on it's forehead

Another interesting thing about this colony was that some of the individuals had a strange white patch on their forehead. I couldn't find any reference to this in any field guide. I believe that more than one individual has this marking.

"Sniff sniff sniff, is that lentil and barley I smell? My second favourite!"

The camera trap didn't stay upright for the full duration. A few days into the session it got knocked over.

Sometimes when your camera trapping subjects decide to "readjust" your camera for you it can turn out for the better, however usually it doesn't...

And what was the last thing the camera saw? Did this fellow have enough of this flashing light interrupting his feasting and decided to put a stop to it?

Here we see the suspect loosening up his foot before undoubtedly unleashing an incredible flying kick that will knock over the Birdcam

Woody Cape Is A Wrap

I'm wrapping up my Woody Cape posts. With the house building now complete I won't have to travel there every month. So, I decided to bring all my cameras back after the December holiday. This will be the last post from the Woody Cape for the time being, but I'm sure I'll continue to do plenty of camera trapping there in the future. There are still many exciting places I want to explore with my camera traps.

Red-Necked Spurfowl (Rooikeelfisant - Pternistes afer) getting up close and personal

With my bad luck at getting proper Genet photographs I'm happy to have gotten some decent enough photographs of them towards the end of the camera trapping session.

Large-Spotted Genet (Grootkolmuskeljaatkat - Genetta tigrina) taking a sniff

Keeping his eye on the prize

I was surprised to get this photograph of a Large-Spotted Genet during the day. But, as usual, it is from behind...

This daytime camera trap photograph of a Large-Spotted Genet was a surprise

This is the first time in over 35 camera trap observations that I've photographed one active during the day (4:37pm to be precise). The rest were all at night, with the exception of two observations that were during the early hours of the morning.

Blue Duiker (Blouduiker - Cephalophus monticola) looking at a path that leads towards a clearing in the forest

That is it from the Woody Cape, for now. I still have a lot of things I would like to do at the Woody Cape, so I'll be back for sure.

Looking Good At The Woody Cape

Camera trapping at a new location usually results in some form of a surprise, and the Woody Cape was no exception.

Aardvark (Erdvark - Orycteropus afer) photographed on a hiking trail in the Woody Cape section of Addo Elephant National Park

I must admit I was surprised to find a photograph of an Aardvark on my camera trap. I consulted my field guides and learnt that these strange critters are in fact widely spread throughout South Africa and can be found in a wide range of habitats. In short they are found anywhere they can find their primary food: ants and termites. In general they prefer ants over termites or other insects, but it is also believed that they might have a sweet tooth for the fruit of a plant called the Aardvark Cucumber.

The other new face that showed up on the camera traps might not be such a big surprise, but I'm glad to finally get a photograph of one on my camera traps inside the reserve.

Common/Grey Duiker (Gewone Duiker - Sylvicapra grimmia) sneaking past the camera trap during the day

What struck me about this Common/Grey Duiker was the rich and dark colour. The Duiker I'm used to seeing are much lighter or greying in colour. As the common name suggests. The dark legs also threw me off. (See some of my older posts over here for comparison.)

In general many of the Woody Cape creatures have struck me as having richer and darker colours than some of their relatives living elsewhere in country.

And while I'm on the topic of colour variation below is a collection of Bush Pig photographs illustrating the colour variation found in the Woody Cape.

First up we have an almost black Bushpig (Bosvark - Potamochoerus larvatus) showing us that going Goth is still not cool

This one sports dark undertones, while showing just enough orange-brown to pull off a classic two-tone look, this youngster finishes off the look with a daring side comb to compensate for the lack of a proper mane

The next pig has nothing to hide, strutting in with confidence and sporting a solid grizzled mane, the rich blaze of orange-brown shows some class and the pose says it all



Needing no fancy poses this fellows laughs the opposition out of the competition, with golden flanks, a bristling mane, dashing cheek whiskers and a snout any mother would be proud of, this pig puts the "ush" in Bushpig

A Dog's Day Out

I've seen a couple of Black-Backed Jackal while traveling through the farmland going from Cannon Rocks towards the Alexandria section of the Woody Cape. However, I was still glad to finally get a photograph of one inside the nature reserve.

 

Black-Backed Jackal (Rooijakkals - Canis mesomelas) darting past the camera in the Woody Cape 

Unfortunately it didn't hang around for long. This is the best photograph I got.

To make up for the lack of Canine images I'll indulge myself and post a few photographs of our dogs enjoying the holiday instead :)

Mushu and Scout interested in something in the sand

Mushu might have the same enthusiasm as Scout, but he doesn't have the same endurance...

 

Cruzin' on the dunes

Scout contemplating where to run off to next

The Woody Cape offers amazing coastal dune landscapes

 



Ahhh nothing better than a siesta after a long day on the beach...

Now, with that out of my system I'll be able to dedicate the next post to the two new faces that showed up on the cameras.