Game Night Drives

Night drives are essentially game drives that operate after dark, with the assistance of a very powerful spotlight. The primary advantage of night drives is that they provide access to nocturnal species that are rarely seen during the day, such as civets, genets, and aardvarks. In some areas, the large cats (particularly lion and leopard) are more active after dark, and there is a greater probability of seeing them hunt.

Over the last week we have done two night drives in order to get a better idea of what nocturnal species inhabit the reserve. On both drives we have seen a variety of owl species, which is great to know they are nesting in the area. We even saw a Speckled Eagle Owl (Bubo africanus) hunt a snake and return to its nest (we think to feed young as they would normally eat prey whole as soon as caught). We have our fingers and toes crossed that we might catch a glimpse of the resident leopards on one of the night drives!

Camera Trapping

Camera traps are remotely activated cameras that are triggered by either motion sensors, an infrared sensor, or uses a light beam. It is a method used for capturing wild animals on film without the researchers having to be present (and therefore altering behaviours). 

Although originally this type of trapping was used in hunting to detect the presence and location of large numbers of game animals, today it is primarily used in research applications including studies of nest ecology, detection of rare species, estimation of population size and species richness, as well as research on habitat use and occupation of human-built structures (such as owl nests etc).

The main benefit of camera traps (also known as trail cameras) is that they can be used to capture images of animals in the wild with as little human interference as possible. In recent decades, with advancements in the quality of camera equipment, this method of field observation has become more and more popular among researchers. Further, this once very expensive form of research has now become relatively affordable.

This week on the reserve I set up a grid of 9 camera traps (300 metres apart) on the side of one of the mountains where a leopard has previously been caught on a camera trap. The cameras will be left out for 4 weeks and checked weekly to ensure the batteries have not run out and the SD cards are not full. I will then bring the cameras in and hopefully there will be some great shots on them, and maybe even a leopard with some cubs! Fingers crossed….I will keep you posted! The picture below shows one of the cameras.

Giraffe hide and seek!

This beautiful male giraffe was trying to hide from me by standing behind an acacia tree! I think you need to try and find a taller tree next time buddy!!!

Behavioural Observations - Ethograms

An ethogram is a catalogue of an animal’s behavioural repertoire. It details the different types of behaviour that are displayed by an animal and hence vary hugely between different species. This list of behaviours, both normal and abnormal, can then be used to complete behavioural observations and studies.

It is essential that all behaviours shown in an ethogram are correctly defined to be mutually exclusive and objective, avoiding subjectivity as to the possible purpose of that behaviour. For example, a rhino may lower its head prior to a charge, but it may also lower its head for a multitude of other reasons, so the behaviour must be recorded as “head lowered” rather than “head lowered as threat of charge”; it is essential not to attach a meaning to a behaviour. Clarity in the definitions of behaviours also helps improve inter-observer reliability. 

Ethograms can be presented both in word and pictorial form. This not only allows for behaviours to be catalogued, but also to indicate the frequency of their occurrence and the probability that one behaviour follows another. The time periods that each behaviour occupies are also often recorded allowing for this to be represented in a pie/bar chart for analysis.

Ethograms are used extensively in the study of animal welfare. They can be used to detect the occurrence or prevalence of abnormal behaviours (stereotypies), normal behaviours, and the behaviour of captive animals upon release into their natural environment.

This week on the reserve I have carried out ethograms on both giraffe and white rhino. Both of these animals present added problems when studying their behaviour. Firstly, they are wild animals and although used to land cruisers and game guards moving around the reserve at distance, they will not carry out their natural array of behaviours if approached at close range. There are two main ways around this issue: the behavioural observations must be completed from a distance, or complete an habituation period prior to each recording session so that the animals become more comfortable in your presence and instead of being vigilant they simply go back to carrying out their natural behaviours (at which point you begin the ethogram). Secondly, there is a large safety aspect which must be considered when studying larger dangerous animals and the safety of the observer must always be paramount.

So far I have carried out my ethograms on foot from a safe distance using binoculars to observe the behaviours. Each ethogram has been done for one hour (recording the behaviours of each individual in the herd every two minutes throughout that hour). As yet there has been no breech of the safety zone and thankfully no rhino charges!!!

The results thus far clearly indicate that no stereotypical behaviours are present and the animals are exhibiting a full range of normal behaviours. This potentially may be due to the very natural surroundings of the reserve and the availability of a huge area in which to freely roam. Arguably, the results may be very different if the same behaviour studies were to be completed on the same species within a zoo environment.