The arrival of 2010 found us sharing our planet with just six remaining sub-species of Tiger. These are the Bengal Tiger (Panthera tigris tigris), the Malayan Tiger (Panthera tigris jacksoni), the South China Tiger (Panthera tigris amoyensis), the Indochinese Tiger (Panthera tigris corbetti), the Sumatran Tiger (Panthera tigris sumatrae) and the Amur Tiger (Panthera tigris altaica).
All of these are endangered with a real threat of extinction in the wild. In recent historical times we have already lost the Javan Tiger (Panthera tigris sondaica), the Bali Tiger (Panthera tigris balica) and the Caspian Tiger (Panthera tigris virgata).
Conservative estimates suggest that less than 3,200 tigers remain. This is in spite of the money being spent on the protection of habitat and guarding the animals themselves. Poaching continues and numbers decline. The good zoos of the world recognise this problem and under the auspices of regional and international zoo bodies they keep and manage tigers for which officially recognised studbooks exist.
The studbooks for the various sub-species show a family tree for all of the included animals which can be traced back to known wild caught founders. Backed up by DNA analysis they help the studbook keeper and species coordinator to advise holders which animals should breed with which. Choices will usually be made to pair up animals of a similar age and which are as unrelated as possible.
Within the United Kingdom, zoo legislation requires that zoos which hold any species (and this incudes tigers) for which a studbook exists then they MUST subscribe to it and the associated breeding programme. Failure to do so would mean losing their zoo licence and so have to close to the public. Sadly such legislation is not International.
The breeding programmes are designed to breed and maintain long term healthy, genetically viable populations which, after training and health screening may be released into the wild at some future date. This is no magic fix and the programmes look towards a possible release a hundred years from now.
Earlier release of tigers is not a viable consideration whilst poaching and habitat destruction continues. Other species may be given consideration where such a move could be of positive benefit to a dwindling wild population. This was done at the end of 2009 with the Northern White Rhinoceros. Sometimes the opposite applies whereby the whole wild population is removed from the wild. This was done with the Californian Condor. Down to just 22 birds in 1987 it was bred protectively in captivity so that there is a population of over 300 today. Over half of these are in the wild. The removal of certain animals from the wild can serve to boost the genetic strength of the captive population.
One of the major problems with the managed population of captive tigers regardless of sub-species is the number of captive spaces. There is not enough. Breeding has to be controlled. Tigers are an easy species to breed but there has to be somewhere to accommodate the progeny. For this reason contraceptive implants are used as is breeding separation and the maintenance of same sex pairs and groups. Numbers in captivity must be controlled and the available genetic range maintained.
The long term survival of the Tiger is under direct and positive threat by those holders of tigers who keep and breed none studbook animals. Those who keep and breed non registered tigers are, without exception, Tiger Farmers. No reputable zoo is going to be interested in the progeny. These animals will, sooner or later, disappear into trade and ultimately end up supplying an illicit market in tiger parts.
These unmanaged tigers are selfishly bred without the remotest consideration to the long term survival to the various sub-species as a whole. Animals are crossed with a sub-specific hybrid brother bred to sister and mother with son. In fact this is deliberately done by collections which keep and breed White Tigers. White Tigers are NOT a species but are a mutation. Most are hybrid mutations. They are of no value to conservation at all.
Those collections which do keep and breed pure bred species but are not a member of an official breeding programme perform no useful function at all. Inevitably the animals they produce will pass on into trade.
No one single collection can have a ‘breeding programme’. Any collection can breed but a breeding progamme needs the cooperation and commitment of a number of collections and the more the better. It does not matter a hoot how ‘rare and endangered’ a tiger is. If it is not in an official breeding programme it is worthless. Zoos which keep and breed or simply keep non studbook animals are not clever they are actually doing harm, albeit indirectly, to the long term survival of the tiger.