Why are some species bold and other skittish ?

[jaylach]

Just as a thought... Some fish are predators and others prey. If I were prey and there were predators in the tank I might be a bit skittish also. Even if in different tanks I would think that this could be a factor if the tanks are close together. Just a thought...

 

[anewbie]

Predators.

Birds.

As aquarists, we try to arrange our tanks to minimize stress, but the stress faced by different Cory species across their enormous geographic range will differ. Is the species adapted to rainforest, under the canopy streams where their instincts are tuned to shade and shadows? Are they from more open habitats? Do they respond to differently coloured substrates, in relation to their camouflage? Is light and fast water their cover? How large are the shoals they move in, in nature?

We can influence how instinct expresses itself, but the most important thing to remember is these are not aquarium fish. They are species evolved in a tough habitat, some of whom happened to be caught and put into the aquarium trade. Instinct does not vanish in a few generations. And since the very basis of what a species is involves difference, it's going to show in behaviour as well as size and colouration.

And this is why guppy frys end up at the top of the tanks; and swordtail frys end up at the bottom of the tank.

 

[itiwhetu]

You must spend time with your fish, when you feed them stay beside the tank as they eat, soon they will see you as a friend. When I have had fish rooms with lots of tanks, I have sometimes had jumpy fish, it is always because they didn't see me enough.

 

[anewbie]

You must spend time with your fish, when you feed them stay beside the tank as they eat, soon they will see you as a friend. When I have had fish rooms with lots of tanks, I have sometimes had jumpy fish, it is always because they didn't see me enough.

That works with some cichild; but not with cory at least my cory. The eques are friendly the sterbai and orange laser are skittish and that is how it has been for 4 years. Actually the orange laser were a bit weird; the first two batches were skittish; the third batch was friendly but then they joined the skittish ones and became skittish (because when one fish flee they all flee); i can't remember which were wild and which were tank raised but I think it was the wild ones that started out tame. Anyway I tend to discount the behavior of albino (that is not a species but a genetic defect in some unnamed species of cory). And yes my various cichlid recognize me. My nijjensi female has been pouting for months since i moved her to a new aquarium (she was a bully in the old aquarium); but my baby angels get all excited when they see me. I once was carrying something and that skilled the heck out of my adult angels but once i set the object down they realize all was fine and came back to the front. I now make sure to keep items low when i carry them in front of the aquarium....

 

[itiwhetu]

That works with some cichild; but not with cory at least my cory. The eques are friendly the sterbai and orange laser are skittish and that is how it has been for 4 years. Actually the orange laser were a bit weird; the first two batches were skittish; the third batch was friendly but then they joined the skittish ones and became skittish (because when one fish flee they all flee); i can't remember which were wild and which were tank raised but I think it was the wild ones that started out tame. Anyway I tend to discount the behavior of albino (that is not a species but a genetic defect in some unnamed species of cory). And yes my various cichlid recognize me. My nijjensi female has been pouting for months since i moved her to a new aquarium (she was a bully in the old aquarium); but my baby angels get all excited when they see me. I once was carrying something and that skilled the heck out of my adult angels but once i set the object down they realize all was fine and came back to the front. I now make sure to keep items low when i carry them in front of the aquarium....

Cichlids are clever, other species dumber but the process is still the same, the more time you spend in front of the tank the better the fish's behavior

 

[Beastije]

I will hijack this thread with my observation/question. I have had the sterbai corydoras for 9 months now. For at least 6 months of that time, they would spend all their time under the driftwood, except when feeding. They would sometimes chase each other and once I have seen spawning behavior attempts. I have had two of them sick and died, so now there are only 13 left. That is why I keep super close eye on them, their barbels and substrate cleaning for the past 5 months or so and thus can tell the change in their behavior. Few months ago they stopped hiding, and instead idle on the substrate in plain sight or in totally different spots, not huddled together under the wood. Sure, there were some changes, less plants, more plants, some rearranging, but overall now the place where they used to hang out is way darker than before (if that was what they wanted, they should be there more), but instead they are more confident, swim among the plants on the top of the tank, chase each other and otocinclus sometimes and they are more lively and a bit different. Due to tetra spawning I assume they also sift through moss and naias plants in the middle of the tank. Ofcourse they hide if I do too sudden move in front of the tank, but otherwise I can watch them as they are looking for food or resting, no stress.

So maybe their behavior is seasonal, or maturity related or they have hiding cycles and skittish cycles? Since for me for example, there were no changes in other inhabitants (except otocinclus, but those came in after the behavior change), in my water change frequency, in feeding, nothing major that would make you go "aha"

 

[DoubleDutch]

I have never had any issues with my sterbai being shy and they live with some rather large fish in a 180 gallon, including a 16" BGK. I also have Peppers, Green Aeneus, Punctatus, Albino, and False Julli. The only ones that were ever shy were the Punctatus when I initially moved them from QT to Main. They were older fish, nearly grown, so I think they were less adaptable in the beginning to being in a busy tank/home. They are not that way any more.

There is also a lot of movement in my home, the tanks have plenty of cover and places to explore, I am always in the tanks for one reason or another so they don't really care about my hands, the siphon, scissors or the net. Half the time they are in my way because they have to see what is going on.

Long story short, I don't think it is a breed specific thing, I think it is more of a social/desensitized thing.

Agree, skittishness isn't species specific.
Even fish that were laid back for quite some time, can get skittish suddenly. Funny thing is my albino sterbai seem to be more outgoing than my normal colored ones hahaha.

I suspect lighting is one of the things that might change things sometimes. I have read several threads in the past years in which switching to LED could cause this.
Don't know exactly why.

BTW : I seriously doubt you actually have C.punctatus as a rare Cory living in Surinam / French Guyana in protected aereas.
A lot of spotted Corys are called Punctatus cause it.means spotted in Latin. They seldom (not tonsay never) are though.

 

[GaryE]

An aspect people don't always consider is how they are in the stores. That's a bare, cold set up with nets suddenly appearing like predators. Some fish arrive spooked.

I have monstera plants in my fishroom, with their broad leaves. Sometimes if I place a plant so those leaves are over the tank, the fish calm immediately. They are very aware of the room outside the glass, and they don't understand it. They do understand foliage as cover.

 

[anewbie]

I will hijack this thread with my observation/question. I have had the sterbai corydoras for 9 months now. For at least 6 months of that time, they would spend all their time under the driftwood, except when feeding. They would sometimes chase each other and once I have seen spawning behavior attempts. I have had two of them sick and died, so now there are only 13 left. That is why I keep super close eye on them, their barbels and substrate cleaning for the past 5 months or so and thus can tell the change in their behavior. Few months ago they stopped hiding, and instead idle on the substrate in plain sight or in totally different spots, not huddled together under the wood. Sure, there were some changes, less plants, more plants, some rearranging, but overall now the place where they used to hang out is way darker than before (if that was what they wanted, they should be there more), but instead they are more confident, swim among the plants on the top of the tank, chase each other and otocinclus sometimes and they are more lively and a bit different. Due to tetra spawning I assume they also sift through moss and naias plants in the middle of the tank. Ofcourse they hide if I do too sudden move in front of the tank, but otherwise I can watch them as they are looking for food or resting, no stress.

So maybe their behavior is seasonal, or maturity related or they have hiding cycles and skittish cycles? Since for me for example, there were no changes in other inhabitants (except otocinclus, but those came in after the behavior change), in my water change frequency, in feeding, nothing major that would make you go "aha"

Were they adults when you purchased them? Did they become adults when their behavior changed ?

 

[Deleted member 149562]

I have two Cory types....Pepper and Bronze

The Bronze are bombproof....when doing anything in the aquarium like tidying up the substrate or doing water changes or sorting the filters, I have to choo them out of the way...."Excuse me..shift your bottoms please!" Stubborn. Stubborn, laid back and bombproof.

The Peppers....a shadow over the glass and they scatter and hide. Aquarium maintenance days they literally vanish from sight...just the occasional twitchy nose peering out from behind a rock and they won't come back out into the open for a good hour or so after the hood is back on the aquarium.

The Peppers will sit huddled with the Bronze and you can almost sense the Bronze telling them to calm down. The Peppers are totally scatty and the Bronze so laid back they are almost falling asleep.

 

[Beastije]

Were they adults when you purchased them? Did they become adults when their behavior changed ?

No they were for sure not adults, i don't think they qualify as adults now even, purchased them from a breeder in October

 

[SomethingsFishy24]

Agree, skittishness isn't species specific.
Even fish that were laid back for quite some time, can get skittish suddenly. Funny thing is my albino sterbai seem to be more outgoing than my normal colored ones hahaha.

I suspect lighting is one of the things that might change things sometimes. I have read several threads in the past years in which switching to LED could cause this.
Don't know exactly why.

BTW : I seriously doubt you actually have C.punctatus as a rare Cory living in Surinam / French Guyana in protected aereas.
A lot of spotted Corys are called Punctatus cause it.means spotted in Latin. They seldom (not tonsay never) are though.

I will have to snap a picture. They could possibly be Delphax or Agassizii as they look quite similar to either, or they could be some weird cross. I don't know but my faith in buying cory cats for what they are sold as is pretty slim at this point.

 

[Biancah76]

I will have to snap a picture. They could possibly be Delphax or Agassizii as they look quite similar to either, or they could be some weird cross. I don't know but my faith in buying cory cats for what they are sold as is pretty slim at this point.

Totally Agree!

 

[dmaccy]

I find reading this very interesting. I have four cory species in my tank. I have a shoal of 8 smudge spot which I hardly ever see as they permanently hide and swim off as soon as they see anyone, which they have done for the entire time I have had them, over a year.
I have albino bronze cory that arent even remotely bothered by my presence, they will sit at the front of the tank and stare at you even if you go right up to them!
And then in the middle I have black Venezuelan and smudge spot cory, both of which will happily swim out the front but can be a bit jumpy if you get too close.

 

[anewbie]

I find reading this very interesting. I have four cory species in my tank. I have a shoal of 8 smudge spot which I hardly ever see as they permanently hide and swim off as soon as they see anyone, which they have done for the entire time I have had them, over a year.
I have albino bronze cory that arent even remotely bothered by my presence, they will sit at the front of the tank and stare at you even if you go right up to them!
And then in the middle I have black Venezuelan and smudge spot cory, both of which will happily swim out the front but can be a bit jumpy if you get too close.

Is there any differences in the two tanks with smudge spot cory that might explain the difference in behavior ?