19 April 2014

The Eland

The last couple of days I've been feeling like my usual online camera trap watering holes have been drying up, so I decided to slip in a post of my own to help quince the thirst of fellow camera trappers out there.

Eland don't need to quince their thirst and can go indefinitely without drinking. They also seem to like knocking over my camera traps. (I guess it is also safe to assume they don't read my blog...)

Eland skull and bones in the sand

While busy traversing the dune fields at Koeberg I stumbled upon this old Eland skull. It has been in the sun and rain for some time and as a result has some good "character".

Interestingly Eland have comparatively small heads for such large animals. Maybe one of the reasons is that large bodies are less susceptible to changes in temperature, and small brains are easier to keep cool.

Eland (Eland - Tragelaphus oryx) camera trapped at Koeberg Nature Reserve

Eland are extremely adaptable antelope, ranging from semi-deserts to woodland, from the coastline all the way up to the slopes of the Drakensberg mountains.

In many semi-arid or treeless environments it can be hard to find shade when you are the tallest thing around. Luckily Eland can handle the sun. In fact Eland can allow their body temperature to increase by 7 degrees Celsius during the day. Such a high temperature would kill a human. Allowing their body temperature to increase so much has a number of advantages. The most obvious one is that it saves a lot of water that would otherwise have been lost if it was used to cool the body.

It is very important to keep the brain at a fairly normal temperature, and the animal will first channel the hot blood from its body to it's nose to cool it off. It will do so by taking quick breaths, up to 70 per minute (compared to the usual 10). The cooled blood is then passed safely to the brain.

This was exactly the shot I was hoping for when I placed the camera trap here

However, Eland aren't true desert antelope that specialise in living in deserts. Historically they occurred throughout much of Southern Africa, but are now restricted to nature reserves and game farms.

I've camera trapped them throughout the Koeberg Nature Reserve and they seem to be a very good fit for the small reserve, performing important ecosystem roles.

Up close and personal with an Eland's feet

Eland don't like to run (gallop) and only do so for short distances when severely disturbed. They prefer to walk or trot (up to 35km/h), keeping it up for several kilometres. What they lack in running speed they make up for in jumping. They are renowned for being excellent jumpers, able to clear 3m high fences.

As soon as the herd spotted me in the distance they huddled together (protecting the young?), by the time I crossed the next dune they were gone

Maybe because Eland aren't good at a fast getaway, they prefer to keep a good distance between the herd and any danger. Luckily thanks to their size they don't need to fear most predators, but unluckily it also makes them an attractive target for those that can hunt them. They might have a hard time dealing with larger predators, such as lions, when they are confined to fenced in reserves that are too small to allow them to put a good distance between them and their predators.

When not threatened by humans Eland can become fairly tame. It almost seems contradictory that when they learn to fear humans they are said to have the longest flight distance of any African game species, at 300-500m.

An Eland herd making its way through the coastal shrub at Koeberg

At the risk of drinking way too deeply of the pool of pseudoscience, I'll leave you with these thoughts to ponder next time you find yourself stuck in traffic or waiting in a queue at the supermarket:

Eland have a long history of living with humankind. They were very important to the ancient cultures that lived in Southern Africa, as can still be seen in many rock paintings and religions. Modern humans have been around in Southern Africa for a long time. It won't be much of a stretch to assume that such a large animal as an Eland must have been a very important food source in mankind's youth. The Eland must have been an obvious target, with early man possibly being a persistence hunter and the Eland being a bad runner. It is interesting to note that the Eland, a non-desert living species, acquire the ability to endure such high body temperatures. The theory of humans hunting using endurance does not seem to be really based on speed or distance, but is largely based on managing body temperature, the availability of water and energy consumption while traveling at relatively slow speeds. What kind of relationship existed between these animals and our early ancestors?

12 April 2014

Loving The Lagomorph

When I started camera trapping at Koeberg I wondered whether I'll be lucky enough to get some Lagomorph action. I haven't seen any Lagomorphs close to Cape Town and after no sign of any hares (yes hares, not rabbits) after years of camera trapping at Tygerberg I had renewed hope for Koeberg. Sadly, after the first few hare-free months I gave up on finding them at Koeberg as well.

So, I was very excited when I got this photo below! When you place a camera trap you have some idea of what you will get and what you might get, but it is really great when a species pops up that you didn't even think of (or gave up on months ago).

Cape Hare (Vlakhaas - Lepus capensis) at Koeberg Nature Reserve

I'm pretty sure that this is a Cape Hare, but I hope to get some more photos to make absolutely sure. We have two species of hare here in South Africa and they are fairly tricky to tell apart. The distribution of both species overlap for large parts of the country, they look more-or-less alike and both can vary considerably in colour and size. The one species prefers slightly more open habitat and the other more cover, but there is a large overlap in habitat preference as well.

I don't know how accurate this is, but I have a feeling that around here (Cape Town) the hare populations have decreased somewhat in recent years. I haven't lived here long enough to know first hand, but based on what I've heard it sounds like they might have been more common 15-25 years ago. My gut feeling would be that the high number of Caracal combined with habitat loss and other ecosystem degradation might be putting a lot of strain on the populations.

The thing with camera trapping is that most photographs aren't "that great" quality, like the hare above, but every now and again you get a fun photograph like the one below.

Small Grey Mongoose (Kleingrysmuishond - Galerella pulverulenta) giving the camera trap a smile

I'll wrap up with this interesting large beetle I photographed at Koeberg. It is amazing what you can find while you are busy setting up a camera trap.

The larvae of the Obese Lily Weevil (Brachycerus obesus) feed on lily bulbs, the adults prefer young leaves