30 January 2010

The Hunt Is On

This Caracal (Rooikat) on the rock looks ready to pounce on something

The Moultrie game camera has been having a great run lately. It was my first camera and while it might be old, slow and take unclear pictures, it still manages to pleasantly surprise me from time to time.

It wasn't long before I got my first full body picture of a Caracal. I think there must be a very dense population of Caracal on Tygerberg. I only started camera trapping on Tygerberg this month and I already got 3 "sightings" of Caracal. They seem to be much more common here than compared to Kirstenbosch. In fact here at Tygerberg I have thus far photographed more Caracals than anything else (except for Four-striped Grass Mice)...

The Bushnell have been having a hard time. I placed the camera in a new location last Monday and by Tuesday it managed to fill the SD card with images of warm leaves... Hopefully things turn around this week for the Bushnell.

26 January 2010

More updates from Tygerberg

Tygerberg as seen from Google Earth

Tygerberg Nature Reserve is actually quite small, but it is big enough to support a hand full of large herbivores and tons and tons of Four-striped Grass Mice (Streepmuis).

(Here is another site with some more information about Tygerburg Nature Reserve.)

Four-striped Grass Mouse (Streepmous) checking out the camera

Making a run for cover

The two sets of dark-light-dark stripes on the back of the mouse gives them their name

I can't stop being astounded at how many mice there are! There is a constant scurrying of mice all around you as you walk along the roads.

I'm very pleased to have gotten a few pictures of some antelope this week. It has been a long time since I last photographed an antelope using a remote camera trap - a Duiker in the Magaliesberg.

Thanks Mr. Bontebok (Bontebok) for posing so nicely for the camera, it's greatly appreciated

The other two visitors to the camera set was a bit less polite and only gave us a glimpse of their rear ends...

A Caracal (Rooikat) passed by the camera one evening

Most of the action was at the Moultrie set, but unfortunately that camera has a very slow trigger speed. The Bushnell camera (with a much faster trigger speed) did not get many visitors, but it was fast enough to photograph the striped mice visiting. The Moultrie was to slow to get a full body shot of the passing Grey Rhebok (Vaalribbik).

A Grey Rhebok (Vaalribbok) also slipped by the camera without having the decency to even show it's face

In recent years two female Grey Rhebok where released at Tygerberg to keep the lonely male company - full story. The Bontebok was also reintroduced - full story.

I moved both cameras yesterday, and I'm hoping to identify some more animal species at Tygerberg. At the moment I'm not focusing on getting "pretty" pictures, but rather trying determine what animals are around and where to look for them. In months to come I will most likely try to get "prettier" pictures, but for now I'm happy with the but shots of Caracal and Grey Rhebok.

19 January 2010

First result from Tygerberg

I set up the cameras on Tygerberg Nature Reserve this weekend (for the first time).

I placed the cameras on Friday afternoon and on Sunday my better half and I went back to check up on them. I wasn't really expecting any animal pictures and basically just wanted to see how the wind is behaving - whether it is filling up the SD memory cards to fast or not. I got some pictures of moving grass and bushes, but no animals. I decided to moved both cameras to better locations and planned on leaving them until later in the week.

When we got home I realised that I forgot to insert a SD card into the Moulrie camera! Luckily it has (20 MB) built in memory, but it wouldn't have lasted long if the wind picked up. So, on Monday I went back to insert the much larger (1 GB) SD card. I also used the opportunity to download the images from the small internal memory. As it turns out it is with this "backup" memory that I got my first animal pictures at Tygerberg Nature Reserve :)

It's not the best shot, but for some reason I like it. I feel that it actually says more than meets the eye at first glance...

Monday morning, some time after dawn, the ears of a Caracal (Rooikat) passes by the camera on Tygerberg, with the city in the background

It is going to take some time to learn how to deal with some of the challenges there, but I am positive that things will work out well. The wind is going to be a problem though and there isn't much to strap a camera onto...

There is a lot of potential at Tygerberg for some great pictures, so lets keep our fingers crossed for some good action during the weeks to come!

18 January 2010

Keeping Company with a Shrew

It is difficult to identify many small mammals when all you have is a "bad" photo. Distinguishing between the different Vlei Rat species is proving difficult, and the fact that different books have different opinions does not help either... Sometimes it gets very tricky to identify beyond genus level. Having the animal in your hands makes it allot easier, but using camera traps one doesn't have that privilege.

Vlei Rat (Vleirot) nibbling on a plant in front of the camera

It is easy enough to assume this is some Vlei Rat species, but which one? In the end I decided to base my decision on The Mammals of the Southern African Subregion by J. D. Skinner and C. T. Chimimba (3rd Edition). The book seems to be reasonably up to date and have a very scientific approach to describing all the mammals in the region. Based on the description and distribution information I would say that this is a Vlei Rat :)

Now, you are forgiven if you think that I might be repeating myself, but actually all members of the genus Otomys are referred to as being "Vlei Rats", but there is in fact also a species called Vlei Rat (Otomys irroratus).

These pictures are a bit out of focus because the animal is sitting to close to the lens

Vlei Rats have a total length of about 24 cm of which about 9 cm is its tail. They weigh approximately 120 g and have a robust stocky appearance with a short tail and a blunt face. They are densely furred with a shaggy coat. The fur is dark but the colour varies geographically. The ears are large and rounded.

Video: Vlei Rat from behind...

Vlei rat's are usually associated with moist, marshy habitats, but can also be found in drier habitats. They have a wide distribution but are more common in habitats associated with damp soil (vleis, along streams or near fringes of swamps). They can be found at considerable distances from water.

They live alone, in pairs or in small groups. They are terrestrial, only entering water when forced too. They are crepuscular (active during dawn/dusk) with some diurnal (day) and nocturnal (night) activity.

Vlei Rats are wholly herbivorous and show advanced specialisation of the digestive tract. They eat plant shoots and the stems of grass, sedges, reeds and other plants. They have a low metabolic rate and low overall minimum thermal conductance. This helps them to adapt to their habitat and habits.

Chris & Tilde Stuart (2008). Veldgids tot Soogdiere van Suider-Afrika. Kaapstad: Struik Uitgewers. 130-131.
John D. Skinner & Christian T. Chimimba (2005). The Mammals of the Southern African Subregion. Cape Town: Cambridge University Press. 171-173.

12 January 2010

As happy as a (Reddish-Grey Musk) Shrew

Finally! I found a shrew. Actually I stumbled upon it. Last week I decided to put my camera next to a boulder, because I couldn't find any better place at the time. I did not expect much from the location and went back 2 days later to move the camera to a "better" area. The camera was set on video mode and when I checked the videos, back in my office, I was very happy! Not only was I surprised to have gotten video footage of animals at all, but I was very surprised when I saw a shrew also frequents the area!

A Reddish-Grey Musk Shrew (Rooigrysmuskusskeerbek)

It took time, some hard research and a night's sleep to convince myself that the shrew in question is a Reddish-Grey Musk Shrew. If you compare this to the shrew I stumbled into in the forest a while ago you might notice the difference in the texture of the hair on the body. I don't have a good enough image of the previous shrew, but after looking at this one I suspect that to be a Forest Shrew. I will have to return to the boulder in the ravine soon, with new motivation to get that shrew.

Possibly sent-marking the edge of the rock using the glands on its body

It is often very difficult to find good information about small mammals and I could find very little concerning this species. In one of the videos it appears to be marking it's territory with sent glands on its body and I found a reference to similar behaviour in another closely related species in the same genus, the Greater Red Musk Shrew. Smell plays an important role for the Greater Red Musk Shrew and particularly males will sent-mark objects in their surroundings using their lateral glands. They also use their neck glands and sometimes their anal glands.

I was definitely surprised at how small this animal is, even compared to other small mammals such as rodents.

The Reddish-Grey Musk Shrew is a small grey to grey brown shrew. The head and body length is about 7.6 cm and weighs about 9 grams. It is widely distributed with a very wide habitat tolerance. It is the most widely distributed shrew in southern Africa. It is predominantly nocturnal, solitary and terrestrial. They can often be found in association with rocks and prefers dense ground level vegetation and deep leaf litter.

Video: Shrew climbing over a rock

They are insectivorous and will eat all sorts of invertebrates. They also consume very small amounts of leaf, seed and other plant material.

Video: Possibly scent-marking on the edge of the rock and then running off

The Afrikaans name for Shrew is Skeerbek, which I rather enjoy. A crude direct translation would be Shave Mouth. I guess it is because its mouth area has less hair and seems as if the hair was shaved off.

The batteries of the Bushnell Trophy Cam finally gave in this week. I have been very impressed with it thus far. The batteries are a lot cheaper and last a lot longer than my Moultrie's. I'm already thinking of saving up for another one :)

I'm hoping to be exploring Tygerberg Nature Reserve with my cameras some time soon so both cameras are at home waiting... Hopefully the camera's aren't here at home for to long...

Gus Mills and Lex Hes (1997). The Complete Book of Southern African Mammals. Cape Town: Struik Winchester. 50.
John D. Skinner & Christian T. Chimimba (2005). The Mammals of the Southern African Subregion. Cape Town: Cambridge University Press. 246-249.

08 January 2010

My Budgerigar Encounter

Earlier this week while I was checking up on my cameras I ran into a Budgerigar (Budgie). It was sitting in the road. Budgies originate from Australia and are kept as pets throughout the world. Sometime birds escape from their cages or are set free by owners that don't want to look after them anymore. Sadly these animals can not survive on their own because they never learned to look after themselves in the wild and usually the natural vegetation is not suitable for them as food.

I used the 'manual picture' setting of the Moultrie camera I had with me to take this picture. It's difficult to aim without a viewfinder, but it turned out pretty good

After thinking the matter through a bit I decided that the poor thing doesn't stand a chance out on the slopes of Table Mountain on its own. So, I tried to catch it. I wanted to bring it back to the office where I have some sunflower seeds for the starving little bird and then I thought I'll have to buy a bird cage and keep it at home. A few tries later I managed to gently catch it using my t-shirt (the only thing with me that could do the job), but as I opened my shirt, to get a better grip, it got out and perched on a tree nearby. I tried again, but then it flew away into the distance, and it was gone. It seemed to be heading towards the Newlands suburb and I hope it will find some bird feeders there full of seed.

04 January 2010

Squirrel gets a surprise on Christmas day

Eastern Gray Squirrel (Gryseekhoring) heading down heads first

The Eastern Gray Squirrel is native to North America. This species has a "good" track record for establishing colonies in non-native countries.

Sitting on a rock next to the stream

The Eastern Gray Squirrel is not considered a big invasive threat in South Africa, mostly because of the location where the introduction took place. The Western Cape has no native squirrels and the habitat (mostly shrubs and heaths) are not very attractive to squirrels which usually prefer areas with more trees. The same conditions that limit the native squirrels from spreading into the Western Cape is also limiting the Eastern Gray Squirrels from leaving the Western Cape. In the Western Cape they are limited to Oak and Pine plantations and suburban gardens.

I very rarely photograph individuals in the native vegetation. If I do get a photo of one it is usually in the forests or the transition between forest and fynbos. These are most likely dispersing individuals looking for new territories and they don't stay in the area for long. However, they are much more commonly found anywhere near Oak trees and the photos in this post where all taken along a small stream at Kirstenbosch with Oak nearby.

So, to get back to the title of this blog entry: On the 24th December I moved my camera a little up the stream onto a branch from an Oak tree that crossed the stream. The next day when the squirrel crossed the branch it did not know what to think of this strange new object in its way, and it spent some time checking it out.

Click the image to view the larger version

But by the next day it was confident enough to do some serious grooming in front of the camera.

Some serious early morning grooming

And some more crazy moves to get at that last spot

My main reason for trying out this area along the stream was to maybe get pictures of an Otter or Water Mongoose, although I think it's a long shot... More realistically I was hoping for some nice Large-Spotted Genet pictures and maybe a Porcupine crossing the stream. No Porcupine appeared, but a Small Grey Mongoose appeared and I did get the tail end of the local genet a few times. Maybe better luck next time.

I have been looking at the rear end of genets for far to long now... I want some mug shots please :)