Shadowing

[YellowFinned]

Only the larger clowns in the big tank do this. Two clowns will swim around nose to nose tail to tail shadowing each other’s movements. All the clowns swirl around in a big mass, and the two shadowing fish will break apart and each shadow another. Not just pairs, I have seen three and four together.

Have not seen this with clowns in any other tank. Have not seen this with other loaches.

Anyone else seen this? Know what it means?

[Nick]

Yep, I've seen my bigger clowns do this...about 3 or 4 times. Though mine did this 'shadowing' only in pairs. Not sure what it was...and I was going to ask but never got around to it At first I thought they were stuck together as they spiralled around - entangled by the spine under the eye...but they eventually broke away from each other unharmed.

[Martin Thoene]

I saw this for the first time the other day, but between a Clown and a Botia histrionica that's about a sixth of the bulk of the Clown. It was literally like the histy was glued to the Clown. It reminded me of a shark with a Remora stuck to it.

Martin.

[Emma Turner]

Mine do this without fail every single evening and have done so for years. Not a single night honestly goes by without some of my clowns doing this. Maybe it is because of the larger sized group I keep. It is always smaller clowns that 'join up' or shadow a slightly larger specimen. Sometimes there are 3 or 4 per fish, and we've even seen Marge with 7 (3 on one side 4 on the other) before now.

Emma

[LoachOrgy]

I have been witnessing all 4 of my 2.5" clowns doing this as well. usually when the lighting is a bit darker around 7pm. Mine also do this in pairs but I notice all 4 of them do it. I see two in particular that do it most but they seem to do it randomely with eachother. I have witnessed my larger clowns doing this in the blue moon light as well. But the smaller ones will do it more dilligently.

[YellowFinned]

Yes Nick, Martin, Emma, Orgy.

What does it mean?

[Emma Turner]

Braz Walker, author of a very good (but quite old) book on loaches and sharks mentions that 'shadowing' was observed in the courtship ritual when breeding Pangio species. He calls it 'parallel swimming'. With these Pangios, he says that once the parallel swimming is observed, spawning is not far away.

However, having seen this in my clowns every night for some years, I feel that what I see is more of a social bonding behaviour of some sort with the littler fish asking for some kind of acceptance from the larger ones. Sometimes the larger ones get so fed up of the joining up/shadowing/parallel swimming (whatever you wish to call it) that they 'snap' - turning round and giving the shadower/s a hefty bite to say 'cut it out'. This doesn't normally put them off, however.

Emma

[Martin Thoene]

Whatever it means, I think it's just another confirmation of the necessity of keeping Clowns (and most Botiine loaches) in groups. They have very deep-rooted social needs that we don't fully understand, and these can never be met if kept singly or as just pairs.

Martin.

[LoachOrgy]

Braz Walker, author of a very good (but quite old) book on loaches and sharks mentions that 'shadowing' was observed in the courtship ritual when breeding Pangio species. He calls it 'parallel swimming'. With these Pangios, he says that once the parallel swimming is observed, spawning is not far away.

However, having seen this in my clowns every night for some years, I feel that what I see is more of a social bonding behaviour of some sort with the littler fish asking for some kind of acceptance from the larger ones. Sometimes the larger ones get so fed up of the joining up/shadowing/parallel swimming (whatever you wish to call it) that they 'snap' - turning round and giving the shadower/s a hefty bite to say 'cut it out'. This doesn't normally put them off, however.

Emma

i often see them shadowing and lightly pecking eachother. i would think from my observation(take note i have no technical or biological experience other than personal experience) that it is some type of social behavior as well. although they do nip at eachother it isn't the general fighting between a few select loaches that occurs. when i see the smaller loaches doing it with the larger loaches it appears to be some type of lesson or teaching in my opinion.

[Emma Turner]

Personally I don't think it can be teaching. It's the smaller ones that join up to the larger 'more experienced' (if you can call it that) loaches, not the larger ones forcing the small ones to shadow and follow.
Having seen this happen so many times over and over again, the ones who are being shadowed can get really annoyed after a short while.
Sometimes it is almost like the little ones are in total awe of the larger specimens. Not only have I seen this on a regular basis, but often there are 2 or 3 separate 'joining up' incidents occuring in my tank at exactly the same time and I always feel really privileged to see this sort of behaviour.

Emma

[Vancmann]

Why Loaches Shadow.
Including my loaches, it is consistent across the board that they shadow one another. Also, I have seen my bigger loach turn around to give a strong snap to the smaller one following that makes me think she is saying, " I have had enough!! Go bother someone else". Sometimes a group of similar sized Clowns shadow each other, like a dance, in a “clump” when they are happy or when they are playing by the waterfall in my river tank. This behavior seems to be programmed in loaches to have that natural instinct to shadow another loach from a small size. Regarding why shadowing happens, I have a Hypothesis based on observing my loaches for many hours at different times and in water movement.
First, some facts:
1. Loaches are highly social, can't exist alone for long (at least happily).
2. They know and remember each other.
3 They sometimes form little sub-groups within large groups.
4. They expend lots of energy to establish leader/pecking order.
5. Their natural habitat exist strong currents, floods and fast flowing waters.
Here are a few assumptions:
In rivers where there can be floods, loaches will have to swim to resist being washed down stream unlike their hillstream cousins who can attach themselves to rocks. They may have to swim vigorously for long periods just to stay in the same place as a group, a tight one, and they will have to have fun doing so.

Based on these facts, I think that loaches do this for two reasons:
1. To stay together as a group. The fact that loaches have a pecking order means they have to establish a group and they have order in the group (pecking order). In the turbulent conditions of their environment, they will have to do what they can to stay in the group and that may be sticking closely to a stronger leader during rough times.
2. To expend less energy fighting the resistance of current.
Birds on long flights do this; they fly in a “V” formation to reduce friction as a group. The leading bird gets rotated out. Since loaches have a bond within their group, they will have to stick together during the monsoon floods or heavy rains. To me it seems that a school of loaches with their mouths bunched up or in a line will have less resistance and a greater chance of sticking together. They can also stick themselves in a log, I guess.

All this said, why my Botia almorhae (Yoyo) tries to shadow my Clowns and Modestas or in the past, Angelfish, African Cichlid, Rainbows, Sharks…. is probably not mating behavior or any of the reasons I discussed. Until we have someone to track, record and document these fish in their natural habitat for a 2-year period, this will only be a hypothesis and they will truly remain a mystery.

[LoachOrgy]

very interesting perspective vance...thanks!

[mamaschild]

I can't say why mine do it, but I've made new observations when adding new loaches.

I picked up a tank a while back, probably 5 months ago, and it came with 2 clowns about 3" and 1 about 5". I never bothered to move them into my group as they seemed quite content in their little group. I recently made some stocking changes and have added them to my group.

I've recently seen my Kubotai shadowing with the smallest ones Possibly they never felt comfy doing it with the big guys? Possibly they are saying, "MY tank, so deal with me"? Not a clue, but it's happening

Now the bigger ones do it a lot, like Emma's....just not quite that often And the Yoyo likes to shadow with everyone but Albert. Chicken

[Vancmann]

And the Yoyo likes to shadow with everyone but Albert. Chicken

This is real funny because my Yoyo reacts the same way with my largest clown loach. He acts real scared around her as if he is intimidated. She prolly would not tolerate him, the yoyo anyways.

Loachorgy, you are welcome. Thought I shared my views.

[YellowFinned]

Why Loaches Shadow.
... loaches will have to swim to resist being washed down stream ... do this for two reasons:
1. To stay together as a group ...
2. To expend less energy fighting the resistance ...

Well thank you Vanc. This is a good explanation.