Did you adjust the temperature of your chameleon tank?
Does your chameleon changes color (either to very bright and colorful or to black) and makes itself look bigger?
Does your chameleon keeps open mouth only near the water source?
Is your chameleon taking big gulps of air while keeping open mouth?
Chameleons are cold-blooded. This means they need a heat source to warm themselves up. However, when the temperature is too high, they will try to cool down by keeping an open mouth. Different species of chameleon require different temperatures. Veiled Chameleon Temperatures – Basking: 85°F – 90°F Ambient: 75°F – 82°F; Panther Chameleon Temperatures – Basking: 87°F – 90°F Ambient: 75°F – 82°F; Jackson Chameleon Temperatures – Basking: 85°F – 88°F Ambient: 75°F – 82°F. Adjust the temperature to optimal for your chameleon and it should fix the gaping mouth problem.
If your chameleon is changing its color and making itself look bigger in addition to keeping an open mouth, it means that he is in a defensive position. Something or someone in his surroundings is causing him stress. Try to find out what is the cause of stress and remove it so your chameleon can feel more comfortable.
Chameleons don’t drink standing water and instead drink water droplets from leaves. In captivity, this means we need to mist our chameleons using either an automatic mister or hand spray bottle. Water can also be provided by a dripper system at the top of a cage. If your chameleon keeps its mouth open near the water source, he is just trying to have a drink.
If your chameleon is keeping its mouth open all day whilst sitting under its basking lamp, seems unalert, isn’t eating or drinking, and is taking big gulps of air whilst tipping its head up, and has a lot of mucus in its mouth then your chameleon most likely has a respiratory infection. This is not something that can be treated on your own so if your chameleon is exhibiting these signs then take it to the vet as soon as possible.
Chameleons often keep their mouth open while shedding. You can recognize if your pet is shedding by flaking skin. Opening its mouth whilst shedding is normal behavior for chameleons.
https://www.chameleonschool.com/yawning-chameleon/
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Sreten null
Hi! I’m Sreten Filipović. I graduated from the Faculty of Agriculture at the University of Belgrade, with a master's degree in Environmental Protection in Agricultural Systems. I’ve worked as a researcher at Finland's Natural Resources Institute (LUKE) on a project aimed at adapting south-western Finland to drought episodes. I founded a consulting agency in the field of environment and agriculture to help farmers who want to implement the principles of sustainability on their farms. I’m also a founding member of the nonprofit organization Ecogenesis from Belgrade whose main goal is non-formal education on the environment and ecology. In my spare time, I like to write blog posts about sustainability, the environment, animal farming, horticulture, and plant protection. I’ve also published several science-fiction short stories.
You can find me on LinkedIn at https://www.linkedin.com/in/sreten-filipovi%C4%87-515aa5158/