corydoras study

[catfishmike]

initaly after becoming interested in corys i got different types to see if they would recognize each other when a new fish was  introduced. would they school together,will they seperate into groups by spiecies,will they have internal disputes?so far none of my corys will form a small shoal,they can tell who each other is but all act independent of each other.some times two bronze corys will prowl around and maybe my two brochis will join in but other than that nothing. i bought more to make them happy but none seem to care much for each other,at introduction my oldest cory will nuzzle the new fish as if it were introducing itself and then promptly leave and end all social behavior.would anyone like to share their experinces with corys?or are my fish just weird?

 

[colesea]

Fish only shoal with other species if 1) they have no choice, and 2) there's a predator about.

But from what I understand of schooling behavior, if you look different from the majority, you're out.

That's why the one of everything type community tanks are bad. Individual fish feel "singled out" thus increasing their stress levels because the fish on its own is the fish that will get gobbled by a predator. Also, the other fish are sending the wrong "social" signals, thus the poor loner doesn't know where he belongs in the pecking order, and may get harassed.

Although there is known to be interspecies hybridization with cories, most fish will prefer to keep to their own kind if there are others of their own kind to chill with.  I've noticed that if you have a mix-matched pair of fish (say a black skirt tetra and white skirt tetra) that school together, the instant you add another black skirt tetra, the two will buddy up and ditch the white skirt tetra, perhaps even picking on it to chase it away.  How do they know their own kind? Colors and patterns is the primary way, behavior (mating displays vary subtly different enough that the females of the respective species can tell even if we humans can't), and pheremones.
~~Colesea

 

[koolkatzfish]

my pygmys used to school with the larger cories I had.

 

[catfishmike]

maybe i should clarify. i've introduceed the same type of fish  just at diferent times.a bronze here two peppered here untill i reached  5 bronze 5 peppered 3 spotted and 2 brochis(which are not corys) i've heard many people say that their corys all sit in segragated groups (spotted over here,stripes over there and no interaction between each other)my fish all act independent of each other regardless of species.