Introduction

Commonly mispelt Sundervall's. Sunderval's jird Meriones crassus, also known as the Jerusalem jird, Silky jird, and Gentle jird, is one of the smallest species of the Meriones genus probably only beaten by the Meriones unigulatus - the Mongolian gerbil. They have a coat resembling the agouti gerbil or Shaw's jirds in colour, but the texture appears much more like a chinchillas, obviously not as dense. The colour is also more uniform and stable throughout the individuals unlike the Shaw’s, which show some degree of variation in each animal. My animals are no longer than 13cm with a tail adding another 10cm to the overall length. The head is pointed with prominent black eyes. The sandy ticked topcoat stops cleanly as it meets the brilliant white under belly. The tail is covered in body coloured hair with a black tip. They have white pointing to the nose and have definite white 'eyebrows'.

It is thought that the animals in the UK are a sub species M. crassus perpallidus, which were illegally shipped into the country.

They are often fondly and a little less formerly known as 'Sunnys'.

Feeding

As with most gerbils and jirds Sundervall's will require a standard rodent mix, a mix with little coloured biscuit is preferred. I find with many mixes that the species will feed selectively and leave certain elements. At the moment as, of 15/08/2001, I use Seddons hamster food of which they leave very little.

They will readily consume all kinds of fruit and vegetable; I have tried broccoli, apple, pear, carrot, sweet potato, and sweet corn. I often dust the fresh food with a vitamin and mineral supplement such as Vionate™ or Nutrobal™ - the latter is preferred.

Jon Hurst, a fellow breeder and friend, assures me that they love hard, stale wholemeal bread; although I have not tried this as yet I am sure it is something they would enjoy.

My group will gnaw and destroy cuttlefish, which not only helps keep teeth in trim but the high calcium content strengthens all bones - it is always available to them.

Need I say that water should be available at all times?

Housing

I only use terrariums to house my gerbil species mainly due to mess reduction and to soften drafts. Jon Hurst uses cages, which he is very happy with, he adds a 'splash' guard around the bottom of the cage to reduce litter being kicked out.

I always add a branch of suitable wood and a nest box is advisable preferably not wood, plastic, or cardboard as this will be destroyed.

Behaviour

Being quite receptive to human contact they rarely bite even when cornered.

Adult individuals may be easily introduced with use of a 'half-way' tank, this will be discussed in a separate article. They can be kept in pairs and/or colonies, there is some advantage to breed in pairs.

This species is mainly nocturnal, but appear more active during the day when pups are around.

I haven't noticed any audible communication between individuals like the characteristic thumping of the hind legs of this genus though others have.

Breeding

Copulation occurs without any special work, similar to that of the Mongolian gerbil. The gestation period is around 22 days resulting in a first litter of usually 1-3, any following litters will average around 3-5. If kept in a colony litter numbers will stay low, 1-2. Weaning age is weeks.

The female may mate after the litter is born (post partum), but fertilisation may be delayed if a litter is suckling.