SAUROMALUS HISPIDUS

General information
The distribution of the Sauromalus hispidus,also called Angel Island Chuckwalla is on the Island “Isla Ángel de la Guarda” (Baja California, Mexico) and the surrounding Islands, San Lorenzo Norte en Sur Islands in the Gulf of California.

Habitat
The climate is characterised as a semi-desert to desert climate with large temperature differences between day and at night time. The area is very dry. The habitat consists mostly of rocks, trees and cacti, but there are always places with sand nearby for the females to lay eggs. The Angel Island Chuckwalla is very territorial, and lives in small groups of 1 man and several females. From December to March, they will hibernate. Chuckwallas are diurnal animals, mostly found basking on the rocks during the day. They will retreat to their caves when they sense any danger or when the temperatures get too high. If there are several dry years in a row this can lead to great numbers of death among the hispidus. The Angel Island Chuckwalla also likes to climb the trees and cacti in search for the flowers and the fruits.

Description
Sauromalus hispidus can have a total length of about 60 cm half of with is tail. An adult Angel Island Chuckwalla weighs about 1,5 kilo. They are sturdy, strong lizards with a big broad head and neck. The are great diggers and are often found in burrows. The have a dark brown almost black colour, and their body is covered with small spiny looking scales. This gives the Sauromalus hispidus his prehistoric appearance.

Housing
Chuckwallas are sun loving animals, and they are really active during the day, so it is recommended to provide a large enclosure with a minimum floor space of 250cm x 100cm. Kamiel keeps his hispidus in a cage with the dimensions : 290cm x 100cm x 75cm. The bigger the enclosure the easier it is to keep a temperature gradient that is good for these lizards. By making a back wall in the enclosure with several different levels you can create extra floor space. Play sand can be used as substrate, but also a clay sand mix with sand or peat. Provide a proper decorated dessert terrarium, you can use rocks or flagstones, etc, (make sure to secure them well so they can not fall and crush the animal) but also lighter material as stumps, branches and bark is used. provide adequate shelters (min. 1 per animal). Chuckwallas love narrow hides, keep this in mind when decorating your enclosure. As Chuckwallas are true sun lovers there can never be an excess of light in the cage. For the heating of my terrarium I use a 60 watt flood lamp, and a 100 Watt self ballasted ReptileUV UVB lamp. In order to create the right temperature gradient you must have more than 1 lamp. An average daily temperature should range between 30 ° C-32 ° C. Under the basking spot the temperature can go up to 55 ° C +, under the other spot 45 ° C. It’s important to have a temperature gradient in your enclosure, in other words make sure you have a hot spot for the animal to bask, and a cool end so your chuckwalla can regulate his own temperature. In the cooler places and in some shelters, the temp should be approximately 25 ° C to 29 ° C. A night temp of 15 ° to 20 ° is enough, so you probably do not have to worry about the night temps. During the summer months, I keep the lights on for approximately 12-14 hours a day. In winter times I slowly reduce this lighting to 6-8 hours of light a day. Very important in the chuckwalla enclosure is an UVB light bulb, I use a 100W self ballasted ReptileUV. Due to the UVB the animal will create D3 witch is important for its health. Besides that, lizards are able to see more colours than humans, some of witch are in the UVB spectrum.

Care
My animals get a nice and fresh greens salad everyday. Main component of this salad is endive. Supplemented with paksoi, bean sprouts, various types of lettuce, chicory, alfalfa, grated carrots, dandelion (if any) grated pumpkin etc.. In the enclosure there also is a dish with bird seeds, red lentils and bee pollen, which are also eagerly taken. As a treat I give them a grasshopper once and a while. Especially when the female is pregnant, I give her slightly more animal protein. I supplement my greens every second feeding with a vitamin / calcium supplement. My Sauromalus hispidus always has a big appetite, and every day he’s waiting for me to fill his food bowl. He also is a messy eater, unlike some Uromastyx species who can very delicately pick something from your hand, the hispidus is likely to bite in your hand while eating. The humidity in the terrarium is low. One of the shelters can be kept slightly moist so that the animals can withdraw to it when they need. Normally, the animals will take the necessary moisture from the food (greens) offered. I do not have a water dish in the enclosure, and did not offer any water the last 2 years, but I do slightly mist the enclosure once a week. I always offer fresh greens daily. If your female is pregnant or the animal is sick you can offer a small and shallow dish with water.

Breeding experience
I have seen mating with my animals several times, but unfortunately the fertility rate of the eggs so far is very low. This might be due to the fact that my females are still young. So far breeding the hispidus seems a little more difficult than breeding the aters.

Incubation of the eggs
In 2012 Kamiel had his first clutch of 16 eggs, unfortunately only 6 eggs were fertile. After 80 days at 31-33 Celcius 4 eggs hatched. This year (2013) I found 18 eggs, but again only 3 this time were fertile. The are still in the incubator as we speak.

Raising the juveniles
Raising the juveniles is roughly the same as the care of the adult animals. The first 2 / 3 months are very important, if the will survive this period, they will probably grow into beautiful big animals. The young animals can be raised together the first 3 months, be careful to watch them closely for aggression, and make sure all animals are eating properly. The slightly weaker animals must be separated so that they can get extra attention. It is wise to give your juveniles the fresh droppings of the healthy adult animals they will eat from it witch will be good for the bacterial in their stomach and intestines. It is also said to be nutritious for them. In addition, they eat the same as the adult chucks. But I have a small dish of water in the enclosure of the young animals, and I spray it twice a week lightly, so they can lick the drops of the enclosure walls. By spraying around the water dish, you will trigger the small animals to drink from the static water in the cup.

Conclusion
The Sauromalus hispidus is a large and lively lizard and will adapt well to captivity if provided the optimal conditions. For this large lizard that means a large enclosure with a temperature gradient, UVB and a variety of fresh vegetables. Especially for the advanced hobbyist this animal is a beautiful challenge to keep and breed. To establish a healthy captive population we will need a lot more breeding results.


Literature

Desert Lizards Captive Husbandry and Propagation (door Randall L. Gray) Krieger Publishing Company Malabar Florida (ISBN 1-57524-160-9)
Sauromalus & Dipsosaurus Verzamelnummer (SDGL / verschillende auteurs)
Reptilia (The european herp magazine) nr. 48 The Genus Sauromalus with notes on keeping and breeding Sauromalus ater (auteur Harry Wölfel)