As wild dogs are moved between the metapopulation reserves in an attempt to mimic natural dispersal patterns they are frequently forced to bond artificially to form new packs (Akcakaya et al. 2007). Gusset et al (2008) have shown that, when reintroducing wild dogs to an area, holding them in a boma (holding enclosure) for a period of time prior to their release increases post-release success (measured in terms of survival and breeding success). This notion is supported by WAG and implemented whenever dogs are translocated to new areas or new packs are artificially formed. Holding bomas for wild dogs (and all other predators) must meet certain criteria when constructed.
General construction of a boma
Bomas designed to hold wild dogs should be approximately 0.5 ha in size. The boma can be constructed in any geometric shape. An electrified fence, maintained at approximately 10 000 volts, of at least 2 m must form the walls of the boma. It is advised that the fence itself be reinforced with diamond mesh on its lower 1.5 m and rock packed along its entire perimeter to prevent break outs and digging.
Adjacent boma with common fence
On some occasions groups of wild dogs are held separately in adjacent bomas with an inter-leading gate, for a period of time before being united. In this way groups can be in olfactory, auditory and visual contact but prevented from physical contact allowing them time to interact through the fence. The goal is to ensure that, when the groups are united, sufficient bonding has already taken place and aggression between the groups would thus be minimised.
It is advised that a ‘double gate’ system be installed when constructing a wild dog boma. This system allows a vehicle to enter the boma without an escape route being presented to the animals in the process. The vehicle drives through the first gate, closing it once through before opening the second gate and entering the boma.
|Water, food and shelter
Fresh water must be supplied to the bomas as frequently as possible
(frequency will depend on climate, temperature, size of drinking trough etc). An example of an effective drinking trough is a circular, concrete-lined depression in the ground, 0.5 m deep and 3 m in diameter.
It should be positioned in a shady area to minimise evaporation. Ideally water should be pumped into the trough remotely so as to minimise human presence in the boma and stress to the animals. Wild dogs have a tendency to wallow and occasionally defecate in water troughs and it is recommended that water is changed every one or two days.
Wild dogs have a tendency to put on weight and lose condition if not fed the correct amount of food while being held in bomas. It is important not to over feed the dogs and, if anything, to slightly underfeed them. In this way they can be kept eager to leave the boma and begin functioning as a cohesive pack upon release. This is not to say that they should be starved in anyway, an example would be to feed a group of five dogs half an impala carcass every second day. To limit potential of disease or parasitic infection it is recommended that old bones and carcass remains are regularly cleared from the boma. If carcass animals have been shot, it is recommended that caution is taken to limit the amount of lead shot which could be ingested by the wild dogs over time by, if possible, removing the portion of carcass where the animal was shot.
It must be ensured that sufficient shade is provided within the boma. The vegetation within the boma should, however, be kept relatively sparse to allow for observation of the animals and access to them should they need to be darted and immobilised for any reason. If possible, grass should be cut in the boma prior to arrival of wild dogs.
Optional additions to bomas Feeding crush
: The presence of a feeding crush in a boma allows dogs to be habituated to a certain area of the boma when feeding and then trapped there should they need to be captured for collaring, transport or medical treatment.
In the De Beers Venetia Limpopo Nature Reserve (a metapopulation reserve), for example, a feeding crush (approximately 20m2) is located in the corner of one of the bomas with the only access to the crush being through a tunnel situated against the side fence of the enclosure. On one end of this tunnel is a gate which could be released by means of a connecting wire to close the crush. In this way dogs could be trapped in the feeding crush.
Veterinarian’s report on wild dogs in bomas –
Dr Peter Caldwell (link to pdf) click