Aggression in breeding bangaii cardinals

[Wolverine]

I've mentioned part of our story with our bangaii cardinals in some other threads, so some of you will know the basics here. Basically, we left any bangaii fry in our tank to their own devices. With eveyr batch, they would be around for a day or two, and then disappear. About a month ago, suddenly a small bangaii that was clearly several months old showed up. Then a few days later one that was a little bit younger showed up. From what we know and have seen, we estimated that the first one to show up was probably 4 months old, and the second 3 months. Now they swim around and eat with the rest of the fish.

Here's what we're wondering about: When these two fry showed up, we saw something we had never seen before; our bangaii cardinals got aggressive. If a clownfish came anywhere near one of the fry, one of the adult bangaii would attack it until it left the area. These were aggressive, open-mouth attacks (they were usually too slow to get to the actual bite). I've seen bangaii to this to other cardinals, but this was the first time I'd seen them do it to other types of fish. And during feeding time they would get really aggressive while the fry came out to eat. They've also been aggressive towards the cleaner and peppermint shrimps and hermit crabs if they're crawling too close to one of the fry.

All of this has calmed down now that the fry are big enough to take care of themselves. And it makes perfect sense, evolutionarily to have the adults protect the fry, but it just doesn't seem that common in fish. Anyway, I was just curious if anyone has seen this happen with breeding bangaii or if ours are just aberrant.

Dave

[JohnL]

Hi Dave,

Welcome back :) You may not have realized that we have a new forum for fish breeding. We are very fortunate to have some of the most knowledgable people as moderators. I am moving this thread there for a better response.

[FMarini]

Dave:
very interesting. i have never experienced this, mainly becuz when i was breeding banggai big time i had only banggais, and they did not interact w/ other fish. Now I can say i have seen this open-mouth charge from female banggais when the male is carrying eggs, and believe me she doesn't care who she assaults. It does make excellent sense for the parents to have some sort of protective response over the fry, and I guess now you one of the first to report it in a home aquarium. I do have a friend local here who is incharge of an 1100gal system where he has about 25 banggais, many are the offsring of the intial parents, and he also has jawfish, and a few angels in w/ these banggai i will ask him if he has ever noted this. I can say that jawfish keep the banggai fry population down, and that in 1100gals of water banggai maintain about 1.5-2ft square territories, and almost never cross these imaginary boundries. But I wlll ask him about the parent care portion. Thanks for the info
frank