Saturday, 13 November 2010

Miscellaneous Mammals: The Sand Cat

When you enter Twilight World, the nocturnal house at Bristol Zoo, one of the first animals you will see are our three Arabian Sand Cats, Felis margarita harrisoni. Sand Cats (there are six subspecies described) have a vast range, extending from Algeria in the west to Baluchistan in central Asia, and have recently been reported from Syria.

Although in many ways similar to the domestic cat (which derives from the Africa Wild Cat Felis sylvestris lybica), Sand Cats have many specialisations for their desert lifestyle and need specialised accommodation in captivity. Most are shown in nocturnal houses, although this is not strictly necessary as they will be active in daylight if food is involved. Incidentally, Bristol pioneered the reverse lighting scheme that enables visitors to observe nocturnal animals during their activity period. The current version opened about 13 years ago.

The Sand Cat can be found in both stony and sandy deserts. It has thick fur on the soles of its feet which insulate it against burning sand and gives traction ob loose substrates. The ears are very large, giving it good hearing in the desert night, and they are tolerant of wide extremes of temperature. They protect themselves during the heat of the day by digging burrows, which can sometimes be several metres long.

The home range of a sand cat is often very large. The size depends on prey availability, but in Israel it is estimated at around 16 km². In the Arabian desert it is even larger, at around 40 km². They may travel between 5 and 10km per night in search of food. For an animal that weighs between 1 and 3 kg that is a lot of ground to cover.

Desert rodents such as gerbils and jerboas are the bulk of prey items, but they will also catch birds and reptiles, including poisonous snakes like Horned Vipers. Sand Cats do not need to drink (although they will if the opportunity presents itself) as they can obtain metabolic water from the process of digestion.

With the spread of deserts in recent years one might think that Sand cats actually benefit from human activities, but so little is known of the species that its current status is uncertain, and is classed as Near Threatened. This may not in fact be the case, but it appears that the distribution is extremely patchy, although this may reflect the distribution of observers rather than the animals themselves. Local populations are susceptible to changes in land use (for example irrigation schemes in Israel and elsewhere), or overgrazing resulting collapse of the small rodent prey base. There are several studies ongoing to investigate the species behaviour and conservation status.

Almost all the Sand Cats in captivity (and the only ones being bred from) are the Arabian subspecies harrisoni. This is to ensure genetic purity of the captive population. The total listed on ISIS is currently 149 individuals, with 6 births in the last 12 months. Bristol bred Sand Cats in the past (our three are the original female and her two youngest daughters), but to avoid overproduction our female has been retired from breeding and the male and male kittens have gone to other collections.

Comparatively few of the smaller cats are to be seen in zoos worldwide, as for the most part they are shy and do not breed easily in a zoo setting where disturbance from then public is unavoidable (big cats don’t worry about such matters). In captivity one problem that their desert adaptations produce (at least in the British climate) is that they are very susceptible to lung disease when the humidity is high. For this reason we have desiccators in their enclosure to keep humidity down. Feeding is not a problem, as it is basically the same as for domestic cats (although one must be careful in making analogies – some wild felines develop eye disorders if not fed on a diet higher in taurine than domestic cats require).

Aside from Sand Cats, other species of Felis that might be seen in a zoo are the Pallas’ Cat F.manul from Mongolia, the Black Footed Cat F.nigripes from southern Africa (essentially the South African equivalent of a Sand Cat), and various forms of the very widespread Wild Cat F.sylvestris (now the only native feline in Britain since the extinction of the Lynx in the early Middle Ages). For some more information on the Scottish Wild Cat, see here:




Next week: Sugar Gliders.

Images from wikipedia

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