My fence lizard is alone. Can I add another lizard without fighting?

Unfortunately, it is common for intact males of the same species to fight, so you may experience that as they get older. They can be very territorial, and it doesn't matter if they are siblings or not. As you mentioned, male and female geckos can (and often will) mate, no matter if they are siblings or not. If you have two females, this would be the most ideal housing situation for multiple animals. Females will often tolerate one another in the same area, however there are exceptions to the rule, and they can fight as well.

Thanks for reaching out about Puff and including a photo. Even if siblings, sharing an enclosure can be stressful. Males, especially during sexual maturation, exude pheromones that can be stressful to the others, male or female. Often bearded dragons do not co-habitate well together, and should be kept separate. Good luck.

Hello, thank you for using Pet Coach. Sexing them is not hard. I suggest you refer to this article. It goes into more detail then I have room for here on this forum. ( http://www.reptilesmagazine.com/Breeding-Lizards/Sexing-Leopard-Geckos/ ) Hope this helps. Best wishes!

WIth some patience and training, they may be able to get along. Consider a pheromone product, such as the Adaptil Collar or DAP plug in diffusers, to decrease any anxiety or aggression in the home. If you have cats, use Feliway Spray or plug in diffusers. You didn't specify the species in the post. Keep them separate, then gradually introduce (or re-introduce) them. First, allow them to hear and smell one another through a closed door. As they progress, you can allow them to see one another but without physical contact. Correct any aggressive or negative behavior immediately. The next step would be to place one of them in a closed carrier and leave them in the same room. Do this for ever increasing periods of time until they are acclimated. Finally, allow short, supervised playtime. Be consistent and praise/reward good behavior. Separate them if they get "rowdy" until they settle down, then reintroduce them.

Leopard geckos can generally co-exist with one another as long as they are male-female pairs or two/more females. They usually do not become territorial while they are young. That being said it is important to make sure they have enough space to escape each other and have more than one hiding area. .If you see bullying, you may need to separate them.

Thanks for your question about Bolt. Having multiple turtles together can lead to some problems, as males can be aggressive to both other males and to females, depending on the time of year. Males don't tend to get along with each other once they hit sexual maturity, and you may end up with injuries or the need for two tanks. Males will typically only be aggressive to females in the breeding season, but the same issues can arise depending on how aggressive the male is being. As far as determining sex, it is difficult to tell visually what sex they are until they are a bit older and getting closer to sexual maturity. There are other techniques that can be utilized such as endoscopic sexing, however you would need to consult with a veterinarian to have this procedure performed. I hope that provides you with some information, and often turtles will do quite well when they are kept alone.

Two female geckos cam live together peacefully as long as the enclosure is of sufficient size. Two males should never be housed together. Gender cannot be determined by the images posted. Males can be differentiated from females by the presence of a V shaped line of pre anal pores just in front of the vent and hemipenal bulges behind it. Your gecko appears to be in the middle of a shed. This is a stressful time for geckos. Provide one or two moist hides in the cage and daily soaks to aid in shedding. Feed appropriately sized prey, no bigger than the space between the eyes, that have been gut loaded for 24 hours prior to offering to maximize nutritional value. Calcium w/D3 and Vitamin supplementation is essential to good health. Consider an exam with your veterinarian or an experienced herp vet to diagnose illness or injury. Submit a stool sample to diagnose intestinal parasites.