Hemibagrus Nemurus Behavior

[DirtyPaws949]

Hello folks!
I have a H. Nemurus, who was free due to living in a small tank and outgrowing it. The old owners also asked me to take their RTC since he was also getting to big for the 40-50 gal, which they shared with other larger-species fish. I quarantined them in my 75gal before moving them to the big tank. Come spring, I am going to get a 800 gal PE tank, and move the catfish and my other biggles to that.

I've noticed the H Nemurus exhibiting odd behavior, where he seems to incessantly rub up against the underside of certain fish— particularly my blood parrot and male JD. He doesn’t appear to be trying to harm the fish, other than annoying them. He’s not biting at their underside, nor trying to gouge them with his pectoral spines.
Back in the day, I had a Raphael Striped Cat who did the same thing to one specific fish.

Can anyone give me insight to this behavior? Is it aggression? An indication that something might be wrong with the fish he’s doing it to?
Thank you ?

PS sorry for the poor video quality and the cloudy water. I had done a water change that morning.

 

[thebiggerthebetter]

Wow, cool observation and question. Refreshing For me, pretty unusual... I think it is the first time I see it or hear of it being done so frequently and so much. I have seen it with my fish every now and then but only once or twice and only for a short time.

I have seen this behavior, which I always assumed has to do with courtship, between my catfish of the same species. I think usually a male tries to swim in synchrony with a female and rub her ventral side, underneath the head, etc. I assume they do it to manifest their intent and to stimulate the female in the wanted direction. I am yet to see a female be impressed by it though haha...

In any case, you have nothing to worry about but rather a chance to observe something educational and beautiful (in my eyes anyway). It seems to me pretty unique and may be thought to be akin to the videos of unusual friendships depicted all over YouTube of goats with ducks, cats and piglets, elephants and donkeys, dogs and chickens, etc. which are mighty heartwarming.

 

[DirtyPaws949]

thebiggerthebetter
Thank you so much for your reply!
that’s interesting that it’s a courtship ritual, and kind of funny! I think I might have to name him Kanye, since he’s a g ay fish ?
Or perhaps he’s just really friendly with them.

The previous owner was rehoming him as a ARTC, and I looked to do some research on them first. If it was an actual ARTC, it would have gotten (very) huge and I read they will kill all their tank mates just because... I came to the conclusion that he’s HN (particularly due to being albino) and that he wouldn’t get as large, but all of the (limited) information I found on them stated they were only slightly less aggressive than ARTC. So I have been diligent about watching out for it.

So far, he’s been a very nice fish, although he dislikes my female Jack Dempsey — he chases her and, man he’s quick!! The only other times I’ve seen him be “mean” were after my other JD male (in the quarantine tank) got mad and bit him for exhibiting the same behavior, they got into a squabble.
And another time while I was feeding them shortly after adopting them, I noticed the RTC had a vent prolapse; I was about to take the RTC out, but then he stole a shrimp from the HN’s mouth— he didn’t appreciate that and tore open the prolapse ?
Surprisingly, the RTC recovered fine, and is still as gluttonous as ever.

Here is a video of my old Raphael Striped Catfish doing the same behavior to a hybrid. Again, sorry for the poor quality, the hosting sites make it awful.

 

[thebiggerthebetter]

This is not an ARTC but as you say H. nemurus, imho. There are two more alternative ID that seem to float around. One of them, if we are indeed talking about the same fish, was mentioned recently by Fishman Dave - Hemibagrus filamentus ( https://www.monsterfishkeepers.com/forums/posts/8189899 ). Maybe he will chime in with more info on his position but we need to be sure first we are talking about the same species.

After the 3 old species of Hemibagrus were split into 18 species, I thought H. spilopterus too but then I reverted back to the nemurus: https://www.monsterfishkeepers.com/forums/posts/7692892

Hemibagrus questions

I have always loved Hemibagrus wyckii and nemurus, and I was reading a thread. In one of the posts it was said that H. wyckii don't usually grow past 24in in captivity, even in large aquaria. So my question to those who have kept wyckii is: is it true that wyckii don't normally grow more than...

www.monsterfishkeepers.com

Our specimen: https://www.monsterfishkeepers.com/forums/posts/7642518

Over the last decade I have come across perhaps a dozen of these fish as adults and none of them broke 1' by much, maybe 14", so they don't grow big in our hands it seems.

They are far gentler than wyckii and wyckioides, nemurus have nothing on the latter two in terms of aggression but they remain a Hemibagrus and thus can be unpredictable and selective.


* * *

I can say for sure I have never seen a raph do this. Wow. IDK what you do to them but this is both hilarious and pequliar.

 

[Fishman Dave]

Hi, certainly a peculiar trait. I think I would agree that it is not an aggressive behaviour. At first I wondered if the cat was shepherding others away from her area but I don't feel that is the case. As Victor says, this is more something akin to courtship. Would be interested to tell if this was a male or female cat though. If it is a male you will see the genital papilla just in front of the anal fin. In h. nemurus you can expect a male to top out at 10" and a female around 14" in my experience.
As for temprament, don't be fooled. My male at 9" got into a fight and tore the fins to pieces on a similar sized Jau leaving him really battered and swam away with zero marks or split fins. This is one cat that can look after itself even with bigger fish. However, they don't seem to look for fights, and certainly generally not with none catfish so I think you should be fine there (although never any guarantees with cats).

H. Filamentus is a different fish again, assuming the one I have is proven to be this fish. Different looking but similar temprement.

H.nemurus is certainly different to the other well known Asian red tailed cat but even then confusion still reigns as h.maydelli could be another even larger version of wykiodes or it could turn out that people are describing regional variants of the same fish.

The problem we have is that we trust the descriptions we are given and so many of these hemibagrus look very similar up to 9" or more.

I would be interested to learn the sex of your fish and interested for you to keep us updated on any changes to this behaviour.

 

[BIG-G]

that’s interesting that it’s a courtship ritual, and kind of funny! I think I might have to name him Kanye, since he’s a g ay fish ?
Or perhaps he’s just really friendly with them.

Do you like fish sticks?
Great name! Lol
Interesting behavior.

 

[DirtyPaws949]

thebiggerthebetter
I think I stumbled upon a couple of the posts you linked during my quest for answers to his species. You were the OP in at least one. This forum yields so much knowledge and perspective —it’s been a great resource to my fishy endeavors. I noted my concerns about aggression to the old owners, and they said he had never bothered anyone.
??‍ I wasn’t looking for a large, aggressive fish, even though I got suckered into taking the RTC too ? from what I’ve read, they’re big, but not particularly aggressive, though they will eat smaller tankmates. I’m hoping he will help me cull some of the ever-multiplying convict cichlids, since none of my other fish do. I know Ill need to rehome the RTC or get an even larger PE tank, but I didn’t want to leave him in the tiny (comparatively) tank. The boy who had him said he hadn’t grown in several months, so he was already beginning to get stunted, and had gill curl on both sides (one side resolved itself so far).

Haha, I’m not sure why my cats are anomalous in their behavior— whatever the case, it’s pretty adorable.I’m just happy this adorable behavior is benign. The JD can hold his own, but my Blood Parrot, Donald, is pretty derpy ? Both the catfish are quickly becoming tank favorites, they are gorgeous, active, confident, and very personable.

Fishman Dave
Thank you so much for the input! I believe the H. Nemurus is male, here are a couple pictures of the genital papilla (I think). Also I measured him to be around 7.5-8”. It’s very difficult to get a good picture of him next to a ruler.
With how he fought with my smaller JD, there’s no doubt in my mind that he could do serious damage if he wanted to.


Him (and my male JD lurking)

I will certainly keep you posted on any changes, and I’ll try to document his love affairs. Oddly, all of the fish that got rub-downs from the catfish were, in my inexperienced opinion, male. (EDIT: I wanted to add, I think I’ve seen this behavior more frequently 1-3 days after larger water changes).

Do you like fish sticks?
Great name! Lol

Thank you!! I was beginning to worry that nobody got the reference. ?

 

[thebiggerthebetter]

DP: I noted my concerns about aggression to the old owners, and they said he had never bothered anyone.
TBTB: That's about typical for these fish IME but every now and then they can become aggressive and predatory too, rarely though, and usually as a response to another aggressive behavior.

DP: I know Ill need to rehome the RTC or get an even larger PE tank,
TBTB: Kudos to you for saving that RTC. Housing RTC doesn't have to be expensive in terms of the enclosure cost if one has space for a large above ground pool or a water storage tub etc. But thinking ahead is very much warranted if one cannot imagine setting up a vessel in the thousands of gallons range for their RTC. Our males at 5-6 years old are 3' and look ok in 4500 gal but the females are 4' and it seems the 4500 gal is not cutting it anymore.

DP: Haha, I’m not sure why my cats are anomalous in their behavior— whatever the case, it’s pretty adorable.I’m just happy this adorable behavior is benign.
TBTB: Another explanation came to my mind involving the known cichlid's tendency to hold feed in their mouth for a while after a feeding and the catfish might be smelling the feed and merely trying to get at it and hence "the tender loving rubbing" might actually be just hunger or greediness...

DP: Both the catfish are quickly becoming tank favorites, they are gorgeous, active, confident, and very personable.
TBTB: Sounds like someone else is succumbing to the catfish bug. And rightfully so. Welcome to the choice of our poison club

DP: I believe the H. Nemurus is male, here are a couple pictures of the genital papilla (I think).
TBTB: I believe you might be right. It doesn't look like a part of the anal fin rays, albeit the size of it throws me off a bit.

DP: I will certainly keep you posted on any changes,
TBTB: I'd love that. If you will, make this thread the "blog" on your nemurus, however regularly or not updated, but all in one spot. It'd be the most helpful and interesting for all, you included.

DP: and I’ll try to document his love affairs.
TBTB: Only in the name of amateur science but be discrete and respectful too please

DP: Oddly, all of the fish that got rub-downs from the catfish were, in my inexperienced opinion, male.
TBTB: Looks more like rub-ups. Anyhow, our poodle used to love doing it to my leg too in the absence of a more worthy object of his desire. I didn't think it made me less of a man Or him less an animal male

DP: (EDIT: I wanted to add, I think I’ve seen this behavior more frequently 1-3 days after larger water changes).
TBTB: Good eye, detective. That, logically, would reinforce the courtship explanation.

* * *

DP: Thank you!! I was beginning to worry that nobody got the reference. ?
TBTB: Between me and Dave, people of slightly older generation, I am sure we didn't get. Or perhaps Dave has but being a gentleman didn't say anything. I still am left out in the clueless timeout but this is not the Lounge forum so I didn't want to ask. Perhaps I still shouldn't despite being tempted (I love understanding ... sometimes to my own detriment) The sexually charged topics are also skating on pretty thin ice with the ToS, so I don't want to get you, me or others or MFK as a whole in trouble. I still grant we wanna have a little fun, even if on a side, haha... but not at the expense of others, if we can, I guess.

 

[DirtyPaws949]

TBTB: Kudos to you for saving that RTC.
Our males at 5-6 years old are 3' and look ok in 4500 gal but the females are 4' and it seems the 4500 gal is not cutting it anymore.
DP: What’s worse it the 13” and 18” plecos that I rescued from 30T gallon tanks... Donald (the bloodparrot) and 75% of the founding convicts came from a situation where they were actively trying to kill them by turning off all equipment. The RTC didn’t grow much while in quarantine, but since moving to the tank he/she is currently housed in, I can see a HUGE difference— especially looking back at pictures from the day I got it. I’ll try and get some pics of it now, and post the before and after. Unfortunately, I cannot accommodate such a large enclosure at this time, getting approval for the 800-gal PE tank as an above-ground-pond was already pushing it with the landlord ? I have another 3-4 years of university if I get my masters, and that’s too long for the RTC to have to wait. After I finish schooling, I intend on getting a large property out-of-state where I’ll have all the room I want for my animal companions. Question: is it okay to swim with your fish in a large enough enclosure? (washing off all chemicals before-hand, of course) because that’s my dream.

TBTB: Another explanation came to my mind involving the known cichlid's tendency to hold feed in their mouth for a while after a feeding and the catfish might be smelling the feed and merely trying to get at it and hence "the tender loving rubbing" might actually be just hunger or greediness...
DP: I thought this was the case too, but he doesn’t do it to the greedy Vieja hybrid (he’s so thick!) or the gluttonous Oscar. BP Donald is probably the fish in the tank with the least extra food to store, courtesy of being deformed.

TBTB: Sounds like someone else is succumbing to the catfish bug. And rightfully so. Welcome to the choice of our poison club
DP: I’ve always loved them, I just never had the pleasure of owning any like these guys before.

TBTB: I believe you might be right. It doesn't look like a part of the anal fin rays, albeit the size of it throws me off a bit.
DP: it’s definitely a separate structure from the fin.
what’s abnormal about it?

TBTB: make this thread the "blog" on your nemurus, however regularly or not updated, but all in one spot. It'd be the most helpful and interesting for all, you included.
DP: that sounds like an excellent idea! I’ll be to keep the nemurus indefinitely, since like my other big fish, he should top out around a foot.

TBTB: Only in the name of amateur science but be discrete and respectful too please
TBTB: Looks more like rub-ups. Anyhow, our poodle used to love doing it to my leg too in the absence of a more worthy object of his desire. I didn't think it made me less of a man Or him less an animal male
DP: Hey, as long as he isn’t hurting anyone, I don’t care what he does. (Sidenote for canine behavior— they’ll do that when anxious/insecure/excited, or when socially awkward and trying to initiate play behavior. Sometimes dominance, but more commonly the aforementioned)

TBTB: Good eye, detective. That, logically, would reinforce the courtship explanation.
DP: yes, I think you and Dave are correct, as the behavior has subsided since the start of the post
* * *
TBTB: Between me and Dave, people of slightly older generation, I am sure we didn't get. Or perhaps Dave has but being a gentleman didn't say anything. I still am left out in the clueless timeout.
DP: it’s from SouthPark, so it’s crude humor, but given the topic, I couldn’t resist. I’ll DM it to you.

 

[Fishman Dave]

Great photos and you are most correct, IMO you have a male and hence the behaviour could indeed be courtship related. I
H. Nemurus appear to be one of the cats who sport a large genital papilla continuously.