7 replies to this topic

[TownForkCreek]

I maintain a large FW community tank that includes a large (8") Festivum cichlid, Mesonauta insignis, as well as an 7" Marginated Madtom, Noturus insignis, raised from a hatchling netted in a nearby creek. (Yeah, I know they're odd tankmates.)

 

Lately, I've been finding my Festivum sporting parallel 3/4" crescent shaped wounds on either side of the hump of his back, just forward of his dorsal fin, as if someone had chomped him. The only 'someone' in the tank large enough to make such a bite wound is the Madtom, whose mouth is about 1" across. The wounds heal up with treatment, but I hate for the Festivum to continue to be injured. I've never actually seen the Madtom bite him, although they occasionally spar. The only other way I can imagine the Festivum getting injured is when he occasionally breaches and bangs against the inside of the aquarium lid. This wouldn't explain the symmetry of the injuries, however. Any of you with experience with Madtoms - is it likely he might be attacking the Festivum, a much larger/bulkier fish?

 

I'm seriously considering re-homing this fish, but I fear returning him to a cold creek after life in a warm aquarium would have unhappy consequences. I don't have a spare tank or even room for another tank and would love to place him with someone else interested in native catfish. He's quite healthy and a really interesting fish, but I'm not willing to continue placing my Festivum at risk. 

 

If you're interested, I'm in North Carolina near Winston Salem. Helpful suggestions are welcome.

[gerald]

Please do NOT release any fish that have been kept in captivity, especially those housed with non-natives.  You may be releasing unseen non-native invasive algae, pathogens, etc along with the fish.   Find him a new home, or kill him if there's no other options.  Have you contacted the Triad Aquarists? Somebody there might want him.  https://www.facebook...iastsofTriadNC/

 

I'm not entirely convinced that the madtom is causing the injuries, but I dont have any better explanation, unless its some sort of bacterial infection that never quite heals.  Seems odd that he would keep biting in the same place, on the top side of the festivum's body.  Usually madtoms dont mess with anything they cant swallow, other than defending their favorite hidey-hole.  Stabbing with the pectoral spines is their usual defense - far more effective than biting.

[Matt DeLaVega]

We do have a trading dock area, but you have to be a NANFA member to view it. Good luck with your margined madtom

[TownForkCreek]

Thanks, Gerald and Matt. I'm pretty careful about not bringing non-native plants onto my property, but to be honest, it had never occurred to me that this fish might have the potential to contaminate the very creek he was netted from. Clearly, I need to start considering a wider scope. I'm eco-sensitive but a relative fish novice. I promise I'll either pass him along to another native fish enthusiast or euthanize him if that becomes necessary, rather than return him to our creek. Thanks for the FB link.

 

The Festivum hasn't shown any evident infection, just a pair of arcs where scales are missing and the underlying skin is roughed up. I was hesitant to blame the Madtom for the injury, which has occurred three times, but the symmetrical arcs are just the right size to match his gape and he's the only other large fish in the tank. If I could just see an attack, I'd know for sure, but they always seem to happen at night. I think I'll try padding the inside of the aquarium lid with a thin sheet of closed-cell foam, to help rule out the possibility of self-injury by the Festivum and continue to observe for a week or so.

[Michael Wolfe]

I think the MM is your culprit.  I have seen two in the same tank literally lock jaws with each other and hold on for almost a minute while they twisted each other around.  I have also seen marks on a Creek Chub that they could not eat, but who was frequently chased out of the preferred hiding spot.

 

So while I normally go with Gerald is always right about these things... I am am going to say that something is going on... but lets ask a few more questions...

 

Where is the MM favorite spot to hide and hang out... does he have a cave... or does he have to hang out in a dense plant... or what?

 

What are the chances that the F is either wandering into that location or actively trying to hide in that same spot?

 

If you get the right combination of answers to the above two question I guarantee you someone is going to get their face bit!

[Michael Wolfe]

oh, and in my opinion belligerent and margined madtom was redundant especially after you indicated a full sized individual.

[Matt DeLaVega]

Though slightly smaller, I am beginning to wonder if MM's are much more aggressive than stonecat.

[gerald]

I guess i've just never kept a madtom who was quite so belligerent.  I've seen them battle with each other and with similar cave-defending fish, but mid-water fish too big to eat were always ignored IME.  Behavior can be unpredictable, and we don't know what insidious role the festivum might be playing in this feud.  Michael's questions & speculations about competition for good hiding spots might be the key.  Adding more caves (coconut halves, clay pots, bamboo) just might solve the dispute.