Elassoma Gilberti

Here is a video of two of my new males having a territory squabble:


The defender:
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The invader:
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The confrontation:
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Aha. Upon closer examination of the "confrontation" photo, you can see a female hiding in the plants. That explains a lot.

Looking at the difference between the chase video and the clamped fin video, it looks like the clamped fin video was more of a timid territorial warning than an aggressive offense. Territorial species often display warnings that if heeded don't result in any sort of offensive action. In one form or another, this is not uncommon in territorial reptiles and mammals also. As a rule there is a preference to avoid actual offensive aggression. Attacks are dangerous and expensive for the aggressor as well, so displays which can achieve the same goal is often preferred.

It would be interesting to document these territorial behaviors with Gilberti in more detail. Is it possible the clamped fin video was a defense of eggs? I would suspect that the reactions and willing to pursue would differ depending on the circumstances under which a territory is being defended, as well as the response of the interloper.

It would be interesting to document these territorial behaviors with Gilberti in more detail. Is it possible the clamped fin video was a defense of eggs?

That male is the only one in the tank who still hasn't found his own territory yet and he keeps getting himself in trouble because of it. Because he doesn't have his own territory, whenever he tries to do a wiggle waggle display at a female he gets chased off, meaning he has never mated before and therefore does not have any eggs to possibly defend. Also, they do not defend their eggs. If they see their fry, they eat them. I've seen it happen. The females as well do not defend their eggs. I've seen the females eat fry.

Edited by EricaWieser, 27 January 2011 - 11:08 AM.

Which male was this without a territory, the clamped fin one or the one being chased in the second video? I don't know much about Gilberti but I was under the impression the male defended the eggs. Perhaps the source I read mistook a male defending territory with defending young. Do they also eat the eggs?

Eating small fry that fail to be skittish enough can confer a survival advantage to the future breeding population. Even eating fry in another territory that a male fails to defend can also have a long term fitness advantage. Yet I can't see this same advantage to a male eating their own eggs, only the fry that fail to be vigorous enough to escape. Of course I'm not talking with any specific knowledge about Gilberti, just very general principles of population genetics. There's almost certainly still a lot to learn about Gilberti.

Which male was this without a territory, the clamped fin one or the one being chased in the second video?

It's the same fish.

The fry that move too much too close to the adults get eaten. The fry that stay motionless near the adults get ignored or still get noticed and then get eaten. Eggs are ignored because they don't move.

I think the male was defending his female. You can see her in the plants he's defending in the "confrontation" photo.

Edited by EricaWieser, 27 January 2011 - 04:04 PM.

The rotifer eggs arrived in the mail! Yay! I am adding the eggs to the tank right now

Update: photo of tank with rotifer eggs floating on surface. That's just one of ten capsules.
If even half of those eggs hatch, it will be insta-pond. Just add water and mix, and poof! microfauna
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Edited by EricaWieser, 27 January 2011 - 05:58 PM.

Interesting. So the feeding triggers toward the young exactly mirrors their normal hunting and feeding style. Simple but effective strategy. It explains why they are so skittish and secretive by nature. You have said that the females attraction is dependent on whether the males are attracting or attacking them at that moment. Is there a pattern you have noticed to when the males attack or attract females, such as timing of previous spawns, female behavior or period since a given female spawned, etc?

I found where I got the idea the male defended the eggs. The wiki article on "pygmy sunfish" says: "Eggs are laid on or beneath dense vegetation, and the male guards the nest area until the fry hatch and scatter." Not a very definitive source, but this tendency to sometime attack and sometimes court females is likely behind nest guarding claim. Of course the same effect can be created by something as simple as a refractory period between spawns, such that the territorial male drives females away for some period after a successful spawn, while being basically oblivious to the eggs.

I know how hive intelligence works in certain species of ants, and what is often perceived as intelligence, or care in this case, is often triggers totally unrelated to intelligence or care. In the case of red harvester ant (Pogonomyrmex barbatus) the decision triggers that leads to 'apparently' intelligent decisions are the result of jaw droppingly simple rules requiring no intelligence, commands, or even communication in the usual sense whatsoever from individual ants. Anyway back to the Elassoma Gilberti, the point is you are likely right that there is no actual care or defense of the eggs involved. Yet it would still be interesting to know what triggers are involved with males attacking verses courting females. Testing the refractory period idea and other possibilities could be done, but would take a lot of work.

Is there a pattern you have noticed to when the males attack or attract females, such as timing of previous spawns, female behavior or period since a given female spawned, etc?

Well, I don't know if I watch them spawn enough to notice patterns. It's just that sometimes after a male has danced a female close like he's going to mate with her, he pecks at her instead and she's like, "Ow!" and flees. He's a bit touched in the head; those attraction spawning dances sometimes end in him loving and sometimes end in him hating her. Sometimes both, one right after another. She doesn't flee very far when he pecks her.

Or sometimes she wanders onto his territory without being lured there, and he'll peck at her, but he's not really attacking her in particular, just sort of a "Get off my land" kind of thing.

Cute tiny baby Elassoma gilberti. I think this is the same one I saw the other day. It seems to have picked out a specific "spot" it thinks is safe. So I dropped microworms on its head.

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Here's another example of a website talking about males protecting the eggs.

http://www.fishchann...h-elassoma.aspx

Males will set up small territories around bundles of plants, or spawning mops, and attract females to them. A mating dance follows, at which time eggs are deposited in the plants. The male will generally drive the female away and then guard the cluster until hatching. The female may eat the eggs.

Again, I don't take this with any level of authority as people tend to jump to conclusions assuming anthropomorphized 'purposes' behind certain observations. Anyway establishing the actual behavioral triggers can be valuable information.

This may lead to a situation making the development of a domesticated, less fearful and secretive, line of Elassoma gilberti relatively easy. This secretive and cautious nature is apparently maintained to a large degree by parental, and other, predation on the young that weed out the less cautious members. By protecting these young and further by selecting the bravest of the young for breeding a more domesticated colony. This is done with Siberian fox in Russia by selecting for low "flight distance". Of course this would make them unfit for a natural environment.

Mywan, I agree, I and I have been trying to slowly socialize the fish. I raised this last batch of young with swordtail dither fish, which made them used to seeing fish their size swim out in open water. And over time I will keep the most flamboyant, visible gilberti, sending off the shy ones to other people when I have to sell them / give them away when they overpopulate the tank. I also have a hairbrained scheme in the back of my mind to introduce Dario dario (scarlet badis) to the tank to see if that will make the Elassoma gilberti more social. But Dario dario are prohibitively rare, expensive, and often sold in male-only groups (that I would boycot for its lack of sustainability) so that hasn't happened yet. But I might get them in the future, if I see a group of mixed gender Dario dario being sold on aquabid or something.

Also, yesterday I went and bought a bag of brine shrimp and dozens of bags of blackworms to add to the tank. I poured the brine shrimp into a next over a bucket (so the salty water didn't get in the tank) and put the net full of pink bodies into the tank. Photo of the result:
Fat gilberti:
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And now there's kind of a mound of worms, chilling in the tank, not going anywhere.
They don't seem to be rushing themselves to work their way into the kitty litter substrate.
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It looks to me like the males display at females, and if she's ready she comes toward him and they spawn. If she doesn't give a response of being receptive, then he attacks her, same as if she was a young male without color.
I have seen gilberti slurp up fry and then blow them out alive. They don't seem to be as predatory on their fry as most fish are. However, larger fry will intimidate smaller fry to where the small ones weaken and die unless there's very abundant food (like Erica's tank).

Would be interesting to put some of those rotifer eggs in a small glass dish and see if they really hatch. I imagine they'll die quick if there's not enough fine particle food (bacteria, yeast, etc).

It looks to me like the males display at females, and if she's ready she comes toward him and they spawn. If she doesn't give a response of being receptive, then he attacks her, same as if she was a young male without color.
I have seen gilberti slurp up fry and then blow them out alive. They don't seem to be as predatory on their fry as most fish are. However, larger fry will intimidate smaller fry to where the small ones weaken and die unless there's very abundant food (like Erica's tank).

Would be interesting to put some of those rotifer eggs in a small glass dish and see if they really hatch. I imagine they'll die quick if there's not enough fine particle food (bacteria, yeast, etc).

This is a new wrinkle in the observations. I suspected some cues from the female to be involved, but had no data to make a distinction or combination with a possible male refractory period following a spawn. Too many variables need tested, and the generalities often stated tend to simply select the easiest explanation. The females might even predate on the eggs to encourage there own spawns. A lot of guessing without much real information. Has a male been observed to spawn while there was still eggs present from a previous spawn?

Predatory fish are often highly competitive and ruthless (if I can use an anthropomorphic term ). Their survival tends to depend on direct competition with and predation of other fish, which also tends to constitute a primary food source. The Gilberti's food source is generally various zooplankton, hence more dependent on secretiveness and quietly stalking the shadows. So the only real advantage to predation on the young, for Gilberti, is to promote the fitness advantage of stealth, with a limited value as a food source. If the adults actually spit the young back out, even a significant portion of the time, it changes things significantly. Have you observed both males and females doing this?

On the domestication issue, perhaps mimicking the flight distance approach used in canines would be best. Acclimatizing them to be less fearful in a given environment can alleviate the observation issues, but this learned behavior is not in itself a heritable trait. You might, however, be selecting heritable traits that are only exhibited under the right environment or training. The trick is to establish a quantitative test of the flight zone under identical conditions. I would wait till they reached sexual maturity, or very nearly so, and place them in a separate bare testing tank (flight tank) one at a time. Maybe one of those cheap plastic *SeaMonkey tanks. Use a cam, or whatever it takes to see the fishes response to your approach at a distance, and select the ones you got the closest to before they reacted. Maybe even use a scarecrow of sorts you can control from the computer, while watching the cam, to keep the flight triggers uniform. Perhaps several distance test averaged together to better control statistical testing variances. The idea is to select breeders based on characteristics which are not dependent on environment or training. Then a secure environment will only improve the results.

Has a male been observed to spawn while there was still eggs present from a previous spawn?

Their eggs are about the same size as a grain of sand, so accurately saying whether or not there are still eggs present from a previous spawn is basically impossible.

And about the last paragraph of your post, well, you don't need to remove the Elassoma from the tank and put it in a testing chamber to be able to tell whether or not it's going to flee. There are Elassoma that will hide at the first sight of your presence in a room and there are Elassoma who will spawn right in front of your big giant face. The difference is temperaments of individual fish is that dramatic. Literally, I'm looking at my tank right now and out of four males, one I haven't seen in three days, one I see hiding in plants staring at me, one I see displaying at a female from within the plants, and one I see nosing back and forth along the front glass. There's a big difference.

Their eggs are about the same size as a grain of sand, so accurately saying whether or not there are still eggs present from a previous spawn is basically impossible.

And about the last paragraph of your post, well, you don't need to remove the Elassoma from the tank and put it in a testing chamber to be able to tell whether or not it's going to flee. There are Elassoma that will hide at the first sight of your presence in a room and there are Elassoma who will spawn right in front of your big giant face. The difference is temperaments of individual fish is that dramatic. Literally, I'm looking at my tank right now and out of four males, one I haven't seen in three days, one I see hiding in plants staring at me, one I see displaying at a female from within the plants, and one I see nosing back and forth along the front glass. There's a big difference.

A few years ago I could see individual grains of sand from across the room. I could even see bugs small enough to crawl in between my fingerprints, or individual color pixels on the TV screen across the room. Nor did I need a microscope to see amoebas or paramecium. Today I am having increasing difficulty reading the text on this forum.

It's cool that the differences in temperament are that great. Apparently you shouldn't need to go to such lengths to get satisfactory results. I probably still would for those that weren't removed for more obvious poor performance, because testing in the worst possible conditions for the fish both maximizes the results and insures the results are independent of environmental factors.

... testing in the worst possible conditions for the fish both maximizes the results and insures the results are independent of environmental factors.

Hmm. No, I don't want to torture my fish. I like it when they're happy.

Speaking of, one of the females is sitting on the big mass of worms, just sitting on them. They haven't really noticed her or started caring yet, but I imagine they will the next time she gets hungry

New video of the Elassoma gilberti:
Male pygmy sunfish dances

Update:
So, I can't really see any rotifers. I'm not sure if you're supposed to be able to see them or not. Maybe I should try following the hatching instructions instead of just dumping the eggs directly into the tank.
Other than that, the fish are doing well. For mywan, the little male got annoyed yesterday at everyone and chased all the females away from his territory. I'm not sure if he's egg guarding or not, but now you've got me thinking that maybe they do defend their territory for the period of time until an egg hatches. Does anyone know how long it takes an egg to officially hatch? I can give my best estimates based upon when I start seeing fry, but I'm curious if there's an official hatch time known?

Does anyone know how long it takes an egg to officially hatch? I can give my best estimates based upon when I start seeing fry, but I'm curious if there's an official hatch time known?

http://nanfa.org/art.../elassoma.shtml

I don't know of any published data regarding hatch time specific to E. gilberti so I'd use the E. okefenokee data since they are so closely related.