Let's talk about something that comes up a lot among axolotl owners.
Will axolotls ever eat each other?
Do they have cannibal tendencies?
Even more intriguing...
What about scary cannibal morphs?
This is important to know when housing multiple axolotls together.
Or if you are trying to raise your own babies from eggs to hatchlings.
So let's look at things closely and see.
Will Axolotls Eat Each Other?
Here is what my own experience as well as the experience of other breeders has taught me.
Let's clear up some myths, first.
The first being, axolotls are not aggressive or mean creatures.
They aren't mean.
They don't bite out of spite.
They're just hungry!
Axolotls are mildly cannibalistic, in that in some cases will bite each other and even eat each other.
This is generally only under certain circumstances.
Biting and Cannibalism in Hatchlings, Babies & Young Juveniles
The first being, growing babies that do not have enough food.
The thing is, babies need a lot of calories as they mature VERY quickly.
Starting from when they first get their front leg nubs (at around an inch) to when they are 4 or 5 inches long, they crave lots of food.
If they aren't getting enough calories because they don't have as much food as they want, they will turn to what is around them, including their siblings.
In most cases of underfeeding with babies you will find nipping going on.
This can result in the loss of gills, fingers, toes, hands, feet, and even whole limbs.
While axolotls can regenerate their limbs (amazingly)...
... This takes away from their energy they would put towards further growth.
It can also lead to the limbs or gills growing back disfigured. :(
The littler ones may even be devoured completely by hungry bigger siblings.
While overcrowding the babies will only worsen the situation and promote cannibalism, sparsely stocking will not do much good if the underlying problem goes unaddressed.
There are really two options:
- Individually separate all young axolotls until they are 5-6" so they cannot bite each other while being fed 1-2x per day
- Provide enough food around the clock so they will *hopefully* not bother each other
Individual separation is probably best for those who are looking to keep a small number of axolotls for pet purposes.
The owner can use the tubbing method, separate aquarium or a tank divider until the axolotl is big enough to be placed with the other(s).
This generally works well.
In some cases though, it's not practical.
When it comes to raising babies, I have tried both methods.
The first method seems at first glance to be best, but unless your FULL TIME JOB is taking care of them, you will most likely quickly find yourself exhausted by all the work.
Trust me on that.
I found that I really needed at least 3-5 hours a day minimum to tend to individually separated axolotls - feeding, removing waste and performing water changes on dozens of containers is a big undertaking.
So now for option #2...
When babies are at the age when they are trying to bite each other (usually around getting their front limbs), switching from the typical baby food (baby brine shrimp) to other food needs to happen.
The question is... what food is that?
Dead food is not good, because if you drop it in, it does not move and they will be more interested in eating siblings that DO move.
So live food is the way to go.
A larger live food that wiggles and moves to entice them to eat that instead of each other will really help.
In this case, live blackworms are ideal.
Provide them with live blackworms around the clock and your babies will seldom, if ever, nip.
It is also much easier on you.
What Size Should Axolotls Be to Be Together?
Once axolotls grow enough to be about 5-6", their enormous hunger begins to fade and they start to require less frequent feedings.
They generally start to lose interest at this point in their tank mates as potential meals.
While a squabble occasionally arise over food, it rarely results in serious harm.
This is, of course, assuming they are properly fed.
It is also not a bad idea to feed them in different areas of the tank to help prevent competition from arising.
Thoughts on Cannibal Morphs
There is discussion among axolotl breeders that axolotls that have eaten siblings may become a "cannibal morph."
The scary part?
Once an axolotl undergoes this change, it will not unlearn this.
It is theorized that axolotls can become cannibal morphs, meaning they may show physiological changes in response to eating their siblings.
This is known to happen with other similar amphibians (source).
Cannibal morphs may develop a different shape to their skull, with wider jaws and a squarer face.
They may also get larger than average size.
Of course, they may forever need to live in solitary confinement to be prevented from injuring another axolotl.
While some breeders intentionally induce cannibal morphs for their own purposes, most try to avoid them by providing ample space and food.
These, of course, make better pets.
Cannibalism in axolotls is not well-studied, but it is certainly a fascinating topic.
The key takeaway is that axolotls are not very cannibalistic by nature, especially when their proper needs are attended to.
Thanks for reading!