24 February 2011

Gerbils Galore

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

The gerbils came out in full force. I was hoping to spot a Hairy-Footed Gerbil amongst them, but it seems that there are only Cape Gerbils at this location.

They were all over the place

They made the best of the bird seed I put out as bait. The camera was set to only take photographs at night, but I'm sure during the day many other creatures also had their fill.

Taking off

All this leaping about reminded me of this great post by the Camera Trap Codger over in America.

The homebrew camera did a good job at its first location. These gerbil shots were what I was after in the first place.

Up close and personal

Camera trapping small mammals can be tricky, but with patience, the right conditions and some luck one can get good results. I enjoy camera trapping the smaller animals (as well as the bigger ones). It is too often that the smaller/elusive/common creatures get over looked.

Putting their backs into it

21 February 2011

The Smell Of Success

Another welcome visitor at the Sony was a Striped Polecat. I haven't photographed many of them at Tygerberg and this is the first good images I've got, so I'm very pleased.

The Striped Polecat (Stinkmuishond - Ictonyx striatus) appears to be searching for something

The Striped Polecat goes under many different names, one of the more popular ones is Zorilla. I always find that name somewhat puzzling. For me the Striped Polecat doesn't look anything like a cross between Zorro and Godzilla... On the other hand it does somewhat resemble what a cross between a pole and a cat might look like (if you have the imagination to back it up) and it is striped...

The Striped Polecat also, naturally, resemble a skunk. Or rather one of the many forms of skunk found in other parts of the world. But in fact these days scientists seem to have separated the skunks from the polecats. Skunks fall into the Mephitidae family and polecats form part of the Mustelidea family.

It seems to have found something to chew on (unfortunately it's not clear what it is from the photograph)

Similarly to skunks (and many other smallish mammals) the Striped Polecat can secrete a foul smelling substance when under stress. They also share a common colour scheme. The black and white pattern is often used by animals as warning colours and I'm sure many would like to avoid upsetting a polecat/skunk if at all possible.

Mmm, what is in here?

Striped Polecats are territorial and aren't usually found at high densities. They make up for this by tolerating a wide variety of habitats and can be found across most of Southern and Central Africa.

This particular individual might have been attracted to the increased rodent activity near the trail camera. The rodents were feasting on bird seed I put out. Cape Gerbils were photographed moments before and during the visit from the polecat, but more about them next time.

18 February 2011

Twice As Sweet As Honey

I was looking forward to plenty of rodent photographs as I approached the new Sony homebrew camera trap at Tygerberg Nature Reserve. As I scanned trough the images I was pleased with the results. I baited the area heavily with bird seed and set the camera to take nighttime photographs only.

I got many rodent photographs, but there where two other species that also visited. The first and most impressive where these two Honey Badgers. I think it might be a mother and her almost grownup youngster.

Two Honey Badger (Ratel - Mellivora capensis) oozing atitude

This is not the first Honey Badgers I photographed at Tygerberg. You can find the previous post and more information about Honey Badgers over here.

I love this picture and I'm very very impressed with the quality of these homebrew cameras. It is a real pity that the lens gears are still giving a few problems. Regardless I'm sure I'll use this camera as often as possible.

13 February 2011

Cat And Mice

Recently I've started stalking Gerbils again. The reason for this is that I recently built my first homebrew camera trap. The camera has a few bugs, but it seems to be working OK. I used our old Sony s600 camera which had a faulty lens. I managed to semi-fix the lens and hooked it up to a YetiCam controller board. It is in the field now trying to get some good nighttime shots of the Gerbils at Tygerberg.

(If you are wondering what on earth a homebrew camera trap is, then I'll save us all some trouble and point you over to RandomTruth's excellent blog post over here.)

A Cape Gerbil (Kaapse Springmuis - Tatera afra) presents us with "his good side"

Getting back to business: So, why am I photographing Gerbils again? Well, a while ago I had my a Bushnell Trophy Cam near the same colony and got some decent videos of their nightly activity. However the Bushnell only takes black and white nighttime photographs and the image quality isn't comparable to the Sony's.

Identifying small mammals from camera trap photographs can be rather tricky and I'm hoping to get a few nice photographs of the resident rodents to see whether there might not in fact be another Gerbil species using the same area.

I tested the camera for two/three nights and got some results. I set it out again last week and I'm hoping for some more success, which has been sorely lacking recently... The camera was not out long, but a Caracal managed to pass by non the less.

Caracal (Rooikat - Caracal caracal) swerving past the camera

The problem with my first homebrew is that the camera itself takes very long to start up. This seems to be related to the broken lens gear that I managed to semi-fixed. At least the lens is working now, but does not seem to be working 100%. I hope I'll find a replacement part sometime, and meanwhile I'm testing to see whether the camera is still usable under certain conditions (and I expect will be).

While I'm on the subject of mice:
A couple of House Mice have been seen around our kitchen so I decided to set out a trap for them. I played around with a few home made models, but in the end I settled on buying a Sherman Trap for future use and convenience. I had some interesting camera trap videos of the mouse outsmarting my home made trap, but I think it got lost along the way. (Being outsmarted by a mouse wasn't something I was awfully concerned keeping a record of...)

The House Mouse (Huismuis - Mus musculus) making a run for it

We took the mouse to a close by park we go to often to walk the dogs at. There are plenty of new (and improved) houses bordering the park, so I'm sure the little guy will settle in quite well.

The mouse is pretty small and dashed around a lot, so taking a good picture without stressing the poor thing out even more becomes very tricky.

run run run run run run run run ... pause "I'm gonna faint!" ... run run run run run run run ... dash for cover "I made it!!"

He dashed for cover as soon as he exited the trap. The funny thing was that he didn't head for the tall grass right next to him, but instead choose the first open space and ran for his life. Only then did he pick out the first decent looking cover and made straight for it. Stopping once or twice to catch his breath (he was running uphill).

The park also borders on Tygerberg Nature Reserve and if his a smart city mouse he'll know to stay out of the country mouse's territory. There are plenty of birds, reptiles and mammals that would love to order a Four-Striped Grass Mouse main meal with a House Mouse on the side...

06 February 2011

Kids These Days

Tygerberg Nature Reserve has a small herd of Bontebok. The females are watched over by a dominant male. He is easy to identify by his red earring and macho attitude. The family spends most of their time near a pond on the eastern slope. However there is also a young bachelor that hangs around at a seasonal pond on the western slope. Dad kicked him out a few years back and he has been living on his own since then. Dad drops by to check up on him every now and again. Now, this young fellow is making my live difficult...

The nose of a culprit: Bontebok (Bontebok - Damaliscus pygargus dorcas)

During December he repositioned the Cuddeback trail camera on the third day of a three week session. This meant this the camera was facing the wrong way for two and a half weeks of the three weeks I left it out. I like the spot and want to keep the camera there, but during January when I reset the camera at the same location the same troubled youth improved my carefully selected camera angle on the very next day after I set it out.

Homing in for the kill...

The camera isn't even really in his way. He must go deliberately out of his way to come mess around with it. For my third attempt I placed it even deeper into the vegetation, hoping to discourage him.

The rest of the Bontebok have much better manners. They seldom take any notice of the camera and when they do they don't completely rearrange the view. Usually I only notice the frame shifting slightly as they nudge it.

The small herd passing by without any trouble

Strictly speaking Bontebok aren't native to Tygerberg. Based on patchy historical records they never occurred as far west as Cape Town where suitable habitat is less extensive than a hundred or so kilometers west where they were/are common. Some records state that they never crossed the mountains that separate Cape Town from the Swellemdam area.

The bottom line is that we might never be sure what their distribution was like in the past. More importantly people sometimes forget that animal distribution and density changes all the time, even in healthy ecosystems. Also, as we humans change our surroundings we alter the habitat and thus the distribution of the animals.

The herd walks single file along the path

Looking at other species that have benefited from agriculture and the availability of water and grassy lawns, it might be plausible that were Bontebok free to roam today (and capable of surviving the roads, etc.) they might have spread "naturally" into the greater Cape Town area thanks to the "unnatural" influence of agriculture and urban development. Naturally the full story will be more complex and involve nutritional requirements, etc. The Bontebok at the reserve and at Table Mountain National Park (close by) seem to be doing well in the nutritionally richer Renosterveld areas and can do well when allowed to select optimal micro habitats such as the pond at Tygerberg. They prefer short green grass of high nutritional value (C4 grasses, etc.) and tend to maintain "feeding lawns".

(Note: These are just some thoughts that crossed my mind, and should not be taken without a pinch of salt - this is not a journal its a blog. The idea is to give you, the reader, something to think about and share my ideas, events and camera trap stories. I'm not an expert in these matters. If I had more time I'd be interested to research the matter more fully, but, alas, I don't.)