Most crested geckos are very calm and docile. Crested geckos also become tolerant of handling and are often very laid back after taming and acclimation. But sometimes, crested geckos can also be aggressive and even bite! In this post, we will discuss why a crested gecko can be aggressive and bite, how to improve the situation and make your crested gecko calmer.
Crested gecko signs of aggression
- Not letting you approach, otherwise becoming angry
- Crested gecko is jumping into glass when you try to approach
- Biting
- Being aggressive when feeding
- Showing aggression when you are trying to handle it
- Watching your every move and following your fingers
- Biting you, and then calming down
- Squeaking and tail swishing
- Increased appetite or refusing food
Reason #1: Your crested gecko feels exposed in the tank
Crested geckos don’t like living in open spaces, and prefer lots of coverage in the terrarium. This is because crested geckos hide and sleep during the day, and only come out when its dark. If your crested gecko’s terrarium has lots of open space, this makes it feel exposed.
Believe it or not, lack of foliage and accessories in the tank can lead to aggression in crested geckos. Make sure to cover 60-65% of the terrarium with fake or real plants, caves, hides and more.
Read more on choosing and even making hides for your crested gecko in this post.
Reason #2: Your crested gecko is not used to you
Just after bringing your crested gecko home, it will be scared and stressed. Imagine how scared your crested gecko is after someone brought it to a completely new place (especially if it was shipped).
Be patient, and let your crested gecko acclimate to new surroundings for around 10-20 days without disturbing it. If your crested gecko seems nervous, you can cover the sides of its tank with cardboard or a cloth. Make sure to house a small crested gecko under 15 grams alone, in a terrarium of less than 10 gallons.
If you approach your crested gecko while it’s still new, it will be either running away from you or being aggressive and try to defend itself. Give it time, and only approach the tank few times a day after your crested gecko seems a little more settled in (at least 5 days or so after bringing home).
After a week or two, you can slowly place your hand in the tank and let it lick some food from your fingers. But before that, only handle it if necessary, when cleaning the tank. It’s a good idea to get another plastic Kritter Keeper like this so you can place your crested gecko there when cleaning the tank.
Reason #3: Other animals/being territorial
Crested geckos can also get territorial, especially during the breeding season. If you have another crested gecko in your house, it can smell it. This is especially true if you handled another crested gecko before – it will smell your hands and can get aggressive.
Your crested gecko might also get angry at other lizards, including other crested geckos. And if you have other pets constantly approaching or passing the crested gecko’s tank, this might also cause aggression.
Reason #4: Your crested gecko associates you with food or is aggressive for food
Some crested geckos love eating bugs and will get excited before and during the feeding time. This can become a problem when a crested gecko becomes aggressive to eat and bites your fingers when catching them.
This can create a habit of being food aggressive. Try to not to handle your crested gecko for bug feeding if it gets too aggressive, to avoid being bitten.
Sometimes, your crested gecko might confuse your fingers with moving bugs. If your crested gecko is following your hands, then it might be the case, especially if it’s dark in the room. Don’t be afraid, as hunting instincts are normal in crested geckos.
Most crested geckos have strong hunting instincts, and will enjoy hunting for and eating bugs. When handling be careful, and remember that it’s natural. If your crested gecko poops on you while handling, don’t put it back to the cage immediately. Otherwise, it will keep continue doing this for you to return it back to the cage.
Some crested geckos will also get aggressive and frustrated if your suddenly remove crickets or other feeder insects from the diet. If your crested gecko enjoys ‘hunting’, catching and eating the bugs, it might get frustrated if you stop offering them. In this case, your crested gecko will be angry and will be trying to run around the tank and hunt for some bugs.
What is more, if you only open the cage to feed live bugs (mainly), your crested gecko will associate door opening with ‘hunting’ for live prey. Try opening the tank without feeding anything, and use a towel or a glove to handle if your crested gecko is biting.
Reason #5: You don’t offer any or enough live insects
A problem of aggression can also arise if you don’t feed any live bugs, and your crested gecko can’t utilize its hunting instinct. Try changing the diet and offering more live bugs, and it might help lower the aggression.
1 or 2 times a week can greatly help improve the situation. Remember to gut-load the feeder insects for 24 hours before offering.
Reason #6: Hormonal changes and/or mating calls
Crested geckos can get somewhat aggressive and bite a lot when going through hormonal changes. This can be when a crested gecko is around 10-20 grams, or around 12-18 months old. Crested geckos grow at different rates, and some a slow growers – reaching only 9-10 grams at 12 months old.
You might also confuse a mating call with biting. If your male crested gecko is biting your fingers during the breeding season, it might be a mating dance and call. Your crested gecko will bite your finger, will vocalize, hunt you around, jump at the glass and try to follow everything around it.
These changes often seem sudden to crested gecko owners, because they tend to be calm and docile before this. These hormonal changes make your crested gecko want to breed and look for a potential mate. Males get very feisty around the breeding season, and this is normal.
Be patient, as aggression in this situations passes with time and age. After changes in light cycle and temperatures, crested geckos become active and ready to breed by March. Crested geckos start breeding at around end of March to November.
Breeding behaviors will start at around 2 years of age. These mating behaviors can last from few weeks to a month or even longer.
Reason #7: Previous traumatic experience
If you have got a juvenile or an adult crested gecko, there is a chance that it was mistreated before. This is especially if you adopt one and don’t know much about its past life.
Crested geckos from pet stores or offered for adoption are often not being properly looked after. Lack of food and water, wrong setup, bullying, and no handling will cause a crested gecko to become competitive or stressed and aggressive.
In this case, you can start providing everything for your crested gecko, let it acclimate and then slowly start handling session and taming. Be patient as your crested gecko is likely to hide, run away from you and bite as it’s feeling scared.
Reason #8: Incorrect handling
If you are not handling your crested gecko correctly, it can get aggressive and unhappy. Never make jerky movements or grab your crested gecko. Also, don’t put your hand over your crested gecko – it will feel vulnerable.
It’s not a good idea to handle crested geckos under 6-8 grams at all – they are very fragile at this point, and get easily scared and even drop the tail. It is easy to crush your small crested gecko or stress it.
You should always approach your crested gecko slowly, and let it come to you instead of taking it yourself. Place your hand in the tank slowly, in a fist, and slowly open the hand (otherwise fingers might look like moving bugs!).
Don’t handle your crested gecko during the morning or the day – let it sleep instead. Crested geckos are crepuscular and get active towards the end of the day. Otherwise, you will disturb and upset it.
You can read a very useful guide on how to handle your crested gecko here.
Reason #9: Your crested gecko has health issues
If your crested gecko has any health issues, it might become aggressive. So if your crested gecko has suddenly turned aggressive, it could be due to internal health problems.
If possible, take your crested gecko to the vet and make sure it doesn’t have any injuries, fractures, impaction or other issues.
Reason #10: Your crested gecko doesn’t like specific objects
Some crested geckos might become angry at specific objects that they don’t like. If you notice that your crested gecko is aggressive and acting angry when you bring the object closer, then it’s the reason. These objects can be different – boxes, watches, necklace and more.
This can even include objects inside the tank that might be interfering with its sleep or day cycle. For example, a loud waterfall installation, bright lights, very high humidity and more.
Reason #11: Shedding
Your crested gecko can become a bit moody during the shedding period. It can also affect the stickiness and appetite. Most crested gecko do not want to be handled or approached when shedding.
This is normal and should pass once the shedding has finished. If there is any stuck shed, prepare a sauna for your crested gecko.
Reason #12: Very small/big cage or the wrong setup
Your crested gecko might feel vulnerable in a big cage if it’s still small. Keep your crested gecko under 15-20 grams in a Kritter Keeper (L and XL) that is up to 6 gallons in size.
Once your crested gecko reaches 20 grams, move it to a terrarium of 15-30 gallons. Very small or large tanks can make your crested gecko aggressive or upset.
What is more, never put your hand from above, as this is predatory behavior. Make sure to place the terrarium on a table/stand and place your hand inside from the bottom or the eye level.
Make sure that humidity and temperature in the cage are optimal. Create a temperature gradient in the cage and let the tank dry out between the higher humidity ranges.
You can read a full guide on humidity and temperatures for crested geckos here.
Reason #13: Sudden changes
If you suddenly change the whole tank or the setup, your crested gecko might react in a negative way. This would not mean that it doesn’t like it, though. Your crested gecko might feel new to the whole territory and will vulnerable and stressed until it has settled there.
Summary:
As you have read, crested geckos can become aggressive due to different reasons. No matter the reason, be patient and try to improve the situation by reviewing the setup and any changes.
If your crested gecko is new, give it a week or two and start handling. But if your crested gecko was docile before and turned aggressive, you will still need to handle it sometimes. In this case, handle 1-2 times a week and use a towel or gloves if you feel scared.
Most crested gecko bites do not hurt and don’t draw blood. Some stronger male bites can hurt a little and draw blood, but this is not too common.
If your crested gecko jumps at the glass when it sees you, it’s a good idea to cover the sides of the tank with a towel or cloth. It will prevent your gecko from seeing you and injuring itself by jumping at glass.
You can read more about getting a crested gecko and bringing it home in this post.