Multifasciatus Aggression

[ctrif]

We have kept 4 multis for about a year and added two new ones about a month ago.

Yesterday my wife noticed a baby! There seems to be only one and our multis have never bread before.

We have been looking at the shell closely for the last 24 hours. We have just done a partially water change and now noticed extreme aggression between the large male and what we thought was a female. This is happening at the entrance to the shell which has a baby in it. The two are jaw locking and tumbling over each other. It looks quite horrible! Don't know what to do. Could this be lead up to mating or is it a fight between to males? I have never seen anything like this before!

Mel

 

[Griz]

He could be trying eliminate fry that are not his. I'll relate what happened in my multi tank which may or may not be relevant. I purchased 1 mated pair and the seller threw in 5 fry as well. It was not known if the fry belonged to this pair or not. The pair settled in nicely at one end of the tank and the 5 little fry stayed at the opposite end. After several weeks, the male began to stalk and try to kill the fry. He got 2 of them before I removed the remaining three. In the meantime there was no signs of this pair breeding at all and they had been proven regular breeders. I posted about this in a shelldweller-specific forum and the most common answer I received was that the male wanted to eliminate the fry that were not his. I had always read that multies were very tolerant of fry, even ones that are not theirs, but apparently a dominant male will sometimes try to eliminate fry that don;t belong to him. Shortly after removing the 3 survivors, the pair had their first batch of 6-7 fry. I don't know if that's what is happening in your case but since you've had no replies I thought I might toss this out as a possibility. It's odd that you've had them this long without them raising fry. What you are seeing sounds more like aggression than mating behaviour, at least from my limited experience with multies. How big is your tank and how many shells do you have?