Chamaeleo jacksoniiJacksons chameleon
Geographic Range
East Africa, namely Kenya and Tanzania. (Zimmermann, 1986).
Habitat
Jackson's chameleons prefer to live in mountain thickets and forests. They need cover to hide in and prefer to live in trees(Bartlett and Bartlett, 1995). They rarely venture to ground except to lay eggs or mate.
- Terrestrial Biomes
- rainforest
Physical Description
Most are approximately 15-35 cm in length. They normally display varying shades of green but can turn as dark as black when in great distress. They are sexually dimorphic. Males have three long, pointed horns protruding from the head. These horns are absent or poorly developed in females. The back of the head displays a small crest. There are small spines along the vertebral line. Like other chameleons, Jackson's chameleon has zygodactylus feet (divided so that two toes point inward and three point outward) which are specialized for tree life, and a prehensile tail which is also used for gripping (Capula, 1989).
The most recognizable feature of all chameleons, however, are their eyes. The pupil is the only part visible from its covering of skin. Each eye rotates a full 180 degrees and is independent of the other. Chameleons have unusually strong control over the curvature of their lenses, and may actually magnify an image. (Land 1995)
Reproduction
Jackson's chameleons have a mating ritual that mimics their threat ritual. The male will initiate the threat display to the female which includes color changes, throat inflation and raising the forelegs toward the opponent. The female then has two choices. She can make threatening gestures back, in which case she does not want to mate. If she does want to mate, she will make weak threatening gestures or make no gesture at all in which case the male recognizes her willingness. The male then will circle around the female, grab her neck in his mouth and pull himself on to her back, and insert his hemipenis into her cloacal opening. This entire process usually lasts about 13 minutes. The female will continue mating for 11 days but with not with the same male twice in one day. Gestation lasts approximately 190 days. The young are usually born in the morning. The female everts her cloaca and the young are delivered one at a time onto a branch. They are still surrounded by a gelatinous egg sac and remain asleep until the egg touches the substrate. The young then awaken and stretch and break through their egg sac. At birth young are about 5.5 cm long and weigh around .6 gm. After 20 days the females will copulate again. The young will reach sexual maturity at the age of 9 or 10 months (Zimmermann, 1986).
Lifespan/Longevity
-
- Average lifespan
Status: captivity - 8.2 years
- AnAge
- Average lifespan
Behavior
Males are territorial and will battle using their horns, which may also be used to attract females. When two males meet, they will turn sideways, flatten their bodies, curl their tails, and thrust their heads forward. They will inflate themselves with air to appear larger and turn brilliant colors. Then they open their mouths to display the varied colors within, while swaying and bobbing with the occasional soft hiss. The submissive male will usually try to hide, will freeze in place, or will try to escape the area. He will fade into drab colors. When males do battle, they will poke each other with their horns and try to push each other off their branches. These fights can cause physical damage to the chameleons
They use stillness and drab natural coloring to protect themselves from predation from birds, snakes, shrews, and lizards.
(Martin, 1990, Zimmermann, 1986).
Food Habits
This chameleon's diet consists mainly of insects and spiders. Using their eyes independently, they will sit completely still and watch for a prey item to cross their path. When one is spotted, both eyes will converge and it will sway a bit to better its vision and to confirm the distance to the meal. Prey is captured by projecting the tongue, which has a fleshy tip covered with sticky saliva. Prey is then brought back into the mouth, chewed and swallowed (Bartlett and Bartlett, 1995). The tongue, one and a half times the lizard's length, can reach full length in a sixteenth of a second.
They obtain water by lapping drops off leaves.
In the morning, they will sun themselves, curving one side towards the light and flattening out their bodies and stretching their necks to increase their surface area. Once warmed, they are able to hunt.
Economic Importance for Humans: Positive
Jackson's chameleons are valuable in the pet trade. They also consume insects.
Conservation Status
The Convention on International Trade in Endangered Species (CITES) lists all chameleons as threatened. Two reasons for their decline are habitat destruction and the exotic pet trade. Demand for chameleons encourages pet suppliers to take them from the wild and ship them great distances; survival rate may be about 1 in 10, and those that survive arrive malnourished and stressed. Proper care methods for these lizards is not well known, so they may be unknowingly mistreated. Captive breeding has been largely unsuccessful, with the exception of the San Diego Zoo and some private breeders.
Other Comments
They are considered a long-lived chameleon (up to 10 years)(Bartlett and Bartlett, 1995).
Contributors
Heather Kundinger (author), Michigan State University, James Harding (editor), Michigan State University.
Glossary
- Ethiopian
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living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
- native range
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the area in which the animal is naturally found, the region in which it is endemic.
- rainforest
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rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
References
Bartlett, P., R. Bartlett. 1995. Chameleons: Everything about Selection, Care, Nutrition, Diseases, Breeding, and Behavior. Barrons.
Capula, M. 1989. Guide to Reptiles and Amphibians of the World. New York: Simon and Schuster.
Land, M. 1995. Fast-focus telephoto eye. Nature, 373: 658-659.
Martin, J. 1990. The engaging habits of chameleons suggest mirth more than menace. Smithsonian, 21: 44-53.
Wolfe, A. 1992. Brilliant!. International Wildlife, 22: 34-39.
Zimmermann, E. 1986. Breeding Terrarium Animals: Amphibians and Reptiles Care, Behavior, Reproduction. New Jersey: T.F.H. Publications.