Elassoma Gilberti

I found some excellent information right here on the NANFA site: http://www.nanfa.org.../elassoma.shtml

E. Gilberti is not on the list, only E. okefenokee, E. evergladei, E. alabamae, and E. zonatum. The time till the eggs begin to hatch in these four range from 82 to 110 hours, four to five days tops. I don't suspect a lot of difference with Gilberti.

Here's what it says about nest guarding:

Vegetation and Egg Deposition
Most of the eggs fell into the fine-leafed Ceratophyllum, where they would stick in small clusters; however, it was common for one or two eggs to drop through to the bottom of the aquarium. After both participants rested briefly, the male chased the female from the spawning site, as she would cannibalize her own eggs. The entire spawning act lasted from 5-6 minutes.

Depending on the species, the male continued to guard the eggs for the next 72-100 hours. If another individual approached, it was confronted by a Sidling Threat Display and chased from the area. When the eggs were being collected for observation, it was not uncommon for the male to bite on the end of the pipette; if that failed to stall collection efforts, he would eat his own eggs. Once the eggs were removed from the spawning site, the male would renew his efforts to spawn with another female.

So the male does defend the eggs, and will apparently eat them if they fail, such as with the pipette. In fact this says removing the eggs will result in the male essentially immediately be ready to spawn again. There's a lot more detailed information on that page I need to think through.

Rotifers:
I would be really surprised at anybody that could actually see them. Back when my eyes were that good I never found anybody that could see them like I could. I could even see the guts in motion. Yet even I either had to put them on a glass I could back light, or in an aquarium simply focus at a given distance into the water and wait for them to drift in and out of focus. Looking through aquarium glass it was an extremely narrow distance range from my eyes that I could actually see them. I could not actually follow them in an aquarium. Seeing them at all is probably out of the question for most people. A set of magnifying glasses from Wal Mart can get me close to what I used to see, but not completely. No matter how clean the imperfections in the glass always limits them.

I did not see Drew's post before posting. It takes me awhile to to post when I am reading up on the information going into the post. That article was the best I have seen yet on Pygmy Sunfishes though.

Here is the breeding behavior data condenses from the American Currents, Winter (Feb.) 1998 reprint, as it pertains to parental "care". Many of the observations provided lacked explicit inclusion of the observational context, leaving room to keep certain extended questions open.

Spawn sequence (general for four members of the genus Elassoma, lacking Gilberti):
(1) Spawn time plus brief rest: 5-6 minutes
(2) Male chases female from spawn.
(3) Guarding continues for 72-100 hours (Sidling Threat Display).
(4) ? - Courting of females resumes (Wiggle Waggle Display).
(5) Start of hatching: 72 to 110 hours.

Presummably the end of the guarding period is observationally triggered by the resumption of the Wiggle Waggle Display, hence (4) is presummed. The statement that females "would cannibalize her own eggs" was not explicitly provided with observational context. I speculated on a male refractory period following a spawn, in which usual territorial behavior while lacking female courting was mistaken for egg protection. The evidence suggest true egg guarding through.

Indicators of true egg guarding:
1: While eggs were being collected with a pipette the males would often bite it in an attempt to deter it.
2: Failing to deter the pipette the male would often respond by 'eating' the eggs, so the eggs are not simply being ignored.
3: Once the eggs are removed the male will return to courting females, step (4), falsifying a refractory period theory.

Open Questions:
*1 Given Gerald's observation of fry being spit back out, it leaves open the possibility the male is not intending to harm the eggs when the authors observed males eating eggs after failing to chase off the pipette.

*2 The article states: "Gravid females could travel through a male’s territory unmolested, another male or non-gravid female would illicit the Sidling Threat Display." Does this also apply to gravid females during the egg guarding period? It would seem that gravid females have the most to gain by eating eggs a male is guarding, because losing the eggs apparently makes the male receptive to spawning. As well as potentially replacing part of the population with her own offspring. Though there is another beneficial effect described below.

Since the males will go back to courting as soon as the eggs are lost females may eat them in a strategy to get the male receptive to her next spawn, or to require the male to invest in the cost of spawning. The effects of the two closely related strategies have slightly different effects. From an evolutionary perspective, for the male to fail to protect the eggs is the same as failing to attract females. This female strategy forces the male to invest more heavily in the offspring to successfully propagate, while freeing the female to produce more offspring. It appears that the main effect of this mating strategy is to relieve the female of much of the cost of spawning, by offloading some cost on the males, in order to increase the total spawning rate of the genus. With a fecundity range between 20 and 70, and a egg survival rate around 50%, averaging 20 to 25 viable eggs per spawn, this turnover rate in spawns would be particularly important when predators are added to the mix. A superficially similar strategy would simply be to benefit maternal genetic heritage and require the females to favor eating fry not likely to be their own.

Most of my primary questions are pretty much answered, with a few stray curiosities that could still be answered. Though there is little doubt that males do indeed guard the eggs in some fashion. There could still be a bit of difference in the specifics of the different members of this genus. E. gilberti was not represented at all in this article, merely assumed relevant. Overgeneralizing this genus could result in some false assumptions in particular cases.

Hmm. Interesting. Today the little male is again chasing away all of the females.

I remember back when the gilberti were in the 10 gallon, I was able to see the eggs laying on top of the sand on the very right hand side of the tank near the glass. I guess the reason why I didn't think he was egg guarding was because the male would stay in the middle of the tank, not hovering above the eggs at all. They sat there half a foot away from him, ignored. But it could be that he was keeping an eye on them. I didn't try to pipette them away. Maybe he would have made defensive measures if I had? I don't know.

Edited by EricaWieser, 01 February 2011 - 07:37 PM.

Photo of one of the males. I now count five of them, I think.
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Fuzzy pictures that are out of focus but have cute poses:
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http://gallery.nanfa...er/two.jpg.html
http://gallery.nanfa.../three.jpg.html

Edited by EricaWieser, 01 February 2011 - 09:50 PM.

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http://gallery.nanfa...resize.jpg.html . . . . . . . . . . . . . . . http://gallery.nanfa...ze_001.jpg.html
Different fish. The one on the left is very antisocial. I had to chase him down with my camera and still could only get three shots before he ran away. The one on the right posed and flared and danced for the camera, flash and all.

Hmm. Interesting. Today the little male is again chasing away all of the females.

I remember back when the gilberti were in the 10 gallon, I was able to see the eggs laying on top of the sand on the very right hand side of the tank near the glass. I guess the reason why I didn't think he was egg guarding was because the male would stay in the middle of the tank, not hovering above the eggs at all. They sat there half a foot away from him, ignored. But it could be that he was keeping an eye on them. I didn't try to pipette them away. Maybe he would have made defensive measures if I had? I don't know.

There was some interesting notes in that article concerning ground spawning, as a result of inconsistent reports in previous published articles. Apparently ground spawning only occurs in the absents of suitable plants. As the eggs are sticky, for clinging to plants, and the male will often attempt to remove the fine particles from the spawn location if they spawn on the ground. It might be that the location of the eggs in the 10 gallon was not where they were originally spawned. The eggs may have also been covered in fine muck due to there stickiness. Especially with kitty litter substrate.

It appears fairly clear that they prefer plant substrates to spawn in, and lacking suitable plants certain substrates are also unsuitable due to fine muck sticking to the eggs, which the male will attempt to clean before spawning if possible.

Elassomid eggs were always found attached to leaves of Ceratophyllum, except in cases where this plant was either not available or in a decomposing state, at which time the eggs were found on the bottom. Because of their semi-adhesive nature, the eggs would become covered with debris soon after they reached the bottom of the aquarium. In his efforts to clear away the debris, the male would clean an area that could be construed as a nest by those familiar with the bedding habits of centrarchid species. Photographs that lend support to this idea were given in Axelrod and Shaw (1967).

It looks like you present setup is ideal as the plant genus Ceratophyllum you are using is the primary plant in their natural environment. The fine leafs of this plants are ideal for catching and adhering to the eggs. The kitty litter substrate is far less than ideal in the event of a ground spawn, due to the particulates that can not be cleaned sticking to the eggs. Sand may fare much better from a ground spawn perspective unless the sand has a fairly large grain size, even then only marginally.

See if you can note how long this male continues chasing off females

It might be that the location of the eggs in the 10 gallon was not where they were originally spawned. The eggs may have also been covered in fine muck due to there stickiness. Especially with kitty litter substrate.

The 10 gallon tank had sand substrate, not kitty litter. When I saw the eggs laying on the substrate, they were laying on sand. This was in a tank absolutely stuffed with Ceratophyllum demersum. The Elassoma gilberti could have spawned in the plants if they wanted to, but since the eggs were on the ground, I'm going to say they're either not sticky or the Elassoma will occasionally ground spawn even with plenty of plants present. A couple of days later there were fry there instead of eggs, so I'd say ground spawning isn't necessarily a bad thing.

The kitty litter substrate is far less than ideal in the event of a ground spawn, due to the particulates that can not be cleaned sticking to the eggs.

Oh, boo, the kitty litter substrate is fine. It's probably pretty similar to the mud they spawn over in the wild.
And kitty litter substrate obeys granular techtonics just like any other substrate. The small particles fall through the bottom of the large ones, with the result that larger surface area particles sit on top.
Some of the recent land-slide areas (the substrate is sloped at about a 70 degree angle, up at the back and down at the front) is fine little particles, but most of the surface of the substrate are pebbles. Picture: http://gallery.nanfa...er/020.JPG.html Picture: http://gallery.nanfa...ze_002.jpg.html So it's not "muck", not by any means. It's more like soft intact clay balls.

See if you can note how long this male continues chasing off females

He's doing his happy dance today, wiggle-waggling at the ladies. I also see fry on that side of the tank, where I haven't before. I bet you're right, and he's spawning again because his eggs hatched. Neat

Edited by EricaWieser, 03 February 2011 - 12:05 PM.

The sponge over the intake of the filter is a success. I'm watching a tiny little fry hang out right next to the sponge, and it's feeling very comfortable in the amount of current there.

Picture:
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They express such a wide variety of colors during the course of their social interactions.
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Mine seem to spawn more on the bottom among leaf litter under the plants (Javamoss and Najas) rather than in the plants. The egg adhesiveness appears to be very weak, if at all. Maybe pH or minerals affects it??

Erica - do you think the fry scatter from the "nest" (egg deposition site) immediately after hatching, or do they stay there and wiggle awhile like Lepomis sunfishes and cichlids? I've never seen hatching occur, and when I do see newborms they're scattered around the tank, never at the nest site.

I keep thinking back to the clamped fin video, while thinking about the Sidling Threat and Wiggle Waggle displays and recalling that you said this male had no territory. Otherwise this looked like a Sidling Threat Display. Perhaps the clamped fin is a tell indicating a non-territorial Threat Display. Something to keep in mind for future observations, to see if this is repeatable.

Many social mammals, such as Meerkat, that have well constrained social restrictions on mating will often have rogue males outside the group that will attempt sneak mate. It would be interesting, however unlikely, to observe a male Elassoma making use of another males territory. It is at least possible, as it relieves that male of much of the usual spawning cost, but with the added cost of a low success rate and threats from territorial males. I doubt such eggs would be effectively guarded, if not eaten by the resident male. Roaming males make more sense in a natural environment where the population density is very limited. A dependence on suitable spawning media can increase local densities in the wild, even when the total population densities are low. Anyway, there is essentially always something new to learn with careful observation.

Something else I am curious about is how fast the turn around rate is for a female to become gravid again following a spawn, relative to the guarding period for the male. The faster this is relative to male guarding the more advantageous it is for females to offload spawning cost on males. Also the mean hatching period for the eggs, relative to the guarding period for the males, effects the evolutionary pressure on the fry to develop faster. The male to female birth rates would also effect these mechanisms, among other things. The article noted embryo development rates, but did not include specific guarding times to compare directly.

Sneaker males are very common in other nest-guarding fishes, such as Lepomis. Their presence in Elassoma is not at all unlikely.

Erica - do you think the fry scatter from the "nest" (egg deposition site) immediately after hatching, or do they stay there and wiggle awhile like Lepomis sunfishes and cichlids? I've never seen hatching occur, and when I do see newborms they're scattered around the tank, never at the nest site.

Yeah, the newly hatched fry do seem to stay where they hatched for the first few days. These fry that just hatched today are hanging out inside the myriophyllum. I saw two there near the sponge. And there were one to three fry on the other side of the tank that spent a few days in the same spot in the roots of the giant water lettuce. In the 10 gallon tank I noticed that the fry mentioned in the previous post stayed where they had hatched for the first few days. They're so tiny and can't move very well. I imagine they wait there as unmoving as possible and eat whatever floats too close to them. Their lack of movement means they're safe around the male. I watched him swim right over and around his fry earlier today, without noticing they were there at all and without them even twitching. They stay perfectly still.

Of course, when I poked the fry with the handle of the net (I wanted to make sure the thing I'd taken a picture of was a fry), it freaked out and swam three inches down and closer to the bacopa monnieri. It's not that they are territorial or emotionally attached to the spot where they first hatch, just that their instincts are all screaming at them not to move and to stay hidden. So since they happen to hatch in a fairly hidden spot and their inclination is to not move much, they tend to stay there. At least until they have grown a little bit and are stronger.

Reminds me of wild fish activity following a rain. Lots of wigglies in your tank .

Yes, there are lots of wigglies. I love the activity. There's so much life in this tank; it's just not necessarily all visible at any given time.

Tank update:
Just now I was about to use the magnetic algae cleaner to clean the dust off the glass. But first I looked at the glass before cleaning it. There are between 15 and 20 little embryo-type fry sticking themselves to the glass! They're super tiny (at first I couldn't see their eyes, and photographing them is impossible). And they're all on the side of the tank where I was shaking cladophora algae out of the ceratophyllum. I bet I uprooted them during cleaning (and I probably threw a couple away with the cladophora, oops). They're so tiny that I can barely see their eyeballs and their stomachs are huuuuge.

Just thought I'd share. Now I know to carefully examine the glass before scraping it with a magnetic algae sponge, because fry might be hanging out on the glass.

Update: there are rotifers in the water. It took me a while to see them because my eyes had to adjust to the scale of them (they're tiny!) but when I was looking at the mostly-belly embryo-fry on the glass, the rotifers moving around became visible, too. All of these tiny life forms are really neat to watch but I'm at a loss at how to share the experience with all of you on the forum because they just don't show up on camera. Sorry, folks.