My Amano's have had eggs in their saddles for months now, but they never lay. Is there a reason why??
I was told how to sex these things, but I still can't tell the difference. I have 8 or 9 shrimp, could I have all females??
Amano shrimp--- eggs in saddle, but they never lay
Moderator: Mustafa
Re: Amano shrimp--- eggs in saddle, but they never lay
My guess is that they do lay the eggs. However, if the eggs are unfertilized, the female will drop them.Shanna wrote:My Amano's have had eggs in their saddles for months now, but they never lay. Is there a reason why??
Yes, especially if you got them from an importer.I have 8 or 9 shrimp, could I have all females??
I am absolutely sure no shrimp has ever layed eggs. I know this for two reasons:
1) I would see the eggs. There is nothing in the tank that would eat them.
2) When the shrimp became mature, they developed eggs. Te eggs have never disappeared---- they are ALWAYS in the shrimps saddles.
Come to think of it, I haven't lately seen a shrimp that DOESN'T have eggs..... so maybe they are all females. I read that the way to tell the difference is in the second row of spots........ the males are perfectly round and the females are a broken line. Is this correct? I have tried to look, but they all look the same to me.
By the way.... I bought them at an independantly owned pet store.
1) I would see the eggs. There is nothing in the tank that would eat them.
2) When the shrimp became mature, they developed eggs. Te eggs have never disappeared---- they are ALWAYS in the shrimps saddles.
Come to think of it, I haven't lately seen a shrimp that DOESN'T have eggs..... so maybe they are all females. I read that the way to tell the difference is in the second row of spots........ the males are perfectly round and the females are a broken line. Is this correct? I have tried to look, but they all look the same to me.
By the way.... I bought them at an independantly owned pet store.
-
chlorophyll
- Shrimp
- Posts: 218
- Joined: Wed Feb 16, 2005 1:22 am
- Location: Hawaii - USA
So... it might actually be true that algae eating shrimp don't lay eggs unless males are present? I suspect this, but haven't strongly looked into it.
This often referred to page does an excellent job of showing and describing the difference between males and females.
http://mikes-machine.mine.nu/breeding_yamato.htm
Another way to end up with all females is if the shop worker had a tendency to go after all the larger specimens for you.
On the other hand, maybe your tank temperature is just not good for breeding. What is yours? I don't know the exact optimal range, but I know mine mated in ~26 C water temperature.
This often referred to page does an excellent job of showing and describing the difference between males and females.
http://mikes-machine.mine.nu/breeding_yamato.htm
Another way to end up with all females is if the shop worker had a tendency to go after all the larger specimens for you.
On the other hand, maybe your tank temperature is just not good for breeding. What is yours? I don't know the exact optimal range, but I know mine mated in ~26 C water temperature.
Mt emperature is EXACTLY the same as yours; 78F/26C!
I read that article too, and I have tried to sex them using this method, but they all look like females too me. Then I think I'm just not doing it right----- ALL FEMALES???-- Out of 10 shrimp (yes, one died)??!!
Another weird thing.... there eggs (in the saddle) seem to shrivel up and disappear once in a while, but they quickly make more...... and never lay.
I read that article too, and I have tried to sex them using this method, but they all look like females too me. Then I think I'm just not doing it right----- ALL FEMALES???-- Out of 10 shrimp (yes, one died)??!!
Another weird thing.... there eggs (in the saddle) seem to shrivel up and disappear once in a while, but they quickly make more...... and never lay.
As Brad said it above it's not unusual to find all females among imported shrimp. And as he also said, they "lay" the eggs, but drop them if they unfertilized. When they drop them depends on the species. With most Atyid (i.e. most of the "algae eating" shrimp) species they seem to drop them very quickly so most hobbyists don't even get to see them. I have seen one small Caridina species from India though that would carry the unfertilized eggs for several days before dropping them.
On the other hand I had a Macrobrachium female living by herself who carried her unfertilized eggs around for over a week.
Hope this helps somewhat.
On the other hand I had a Macrobrachium female living by herself who carried her unfertilized eggs around for over a week.
Hope this helps somewhat.
-
GunmetalBlue
- Shrimpoholic
- Posts: 263
- Joined: Sat Apr 16, 2005 11:10 am
- Location: CA
The shrimp most likely eats them and is probably good for them too. Or at the least, picks through them, just like how they might pick through molted exoskeletons. By the time you notice, they're gone or unrecognizable as dropped eggs.
Some Macrobrachiums seem to hold their unfertilized eggs longer, at least for a couple or more days. When mine used to have unfertilized, soon to drop eggs, I used to watch her very carefully as she cleaned herself. I would see her very quickly nudging around in her pleopod with her appendages as if she were sorting/cleaning her eggs and... I tried to catch her and see if in reality she was checking to see which ones were about to drop so she could literally take it out and eat it. Alas, the movements were too quick and the eggs too small to actually confirm one way or another if she was taking them directly from her pleopod and eating them one by one. But the number of eggs she had would slowly decrease.
-GB
Some Macrobrachiums seem to hold their unfertilized eggs longer, at least for a couple or more days. When mine used to have unfertilized, soon to drop eggs, I used to watch her very carefully as she cleaned herself. I would see her very quickly nudging around in her pleopod with her appendages as if she were sorting/cleaning her eggs and... I tried to catch her and see if in reality she was checking to see which ones were about to drop so she could literally take it out and eat it. Alas, the movements were too quick and the eggs too small to actually confirm one way or another if she was taking them directly from her pleopod and eating them one by one. But the number of eggs she had would slowly decrease.
-GB
-
chlorophyll
- Shrimp
- Posts: 218
- Joined: Wed Feb 16, 2005 1:22 am
- Location: Hawaii - USA
I guess you must have all females, huh? 
About them eating the eggs, I find that likely too. These shrimp seem to have larger appetites than others. And I wouldn't be surprised if they don't drop the eggs but just take them right off their tails. The eggs are also extremely tiny... each one probably less than 0.25 mm in diameter.
I had a problem with my first hatch this weekend where I may not have been providing enough food for the isolated female. But Saturday the eggs (which were ready to hatch) were all gone and I couldn't find any larvae swimming or dead on the ground. I'm not sure what happened, but it seems the female quite thoroughly eliminated the evidence.
Over this same weekend though, I had an explosion in activity and at least 3 more females now have eggs. One more in my 26 Celsius tank (actually this is the same female I was talking about above... she had a one day turnover) and two in 23.5 C. A 4th berried female (from the 26 C) now has 20+ day old eggs..
About them eating the eggs, I find that likely too. These shrimp seem to have larger appetites than others. And I wouldn't be surprised if they don't drop the eggs but just take them right off their tails. The eggs are also extremely tiny... each one probably less than 0.25 mm in diameter.
I had a problem with my first hatch this weekend where I may not have been providing enough food for the isolated female. But Saturday the eggs (which were ready to hatch) were all gone and I couldn't find any larvae swimming or dead on the ground. I'm not sure what happened, but it seems the female quite thoroughly eliminated the evidence.
Over this same weekend though, I had an explosion in activity and at least 3 more females now have eggs. One more in my 26 Celsius tank (actually this is the same female I was talking about above... she had a one day turnover) and two in 23.5 C. A 4th berried female (from the 26 C) now has 20+ day old eggs..
-
chlorophyll
- Shrimp
- Posts: 218
- Joined: Wed Feb 16, 2005 1:22 am
- Location: Hawaii - USA
I personally don't know why some importeres might only have females. The others sound like they know more about this. I don't know if it's deliberate or what. All I can think of is that it's a size issue, and when they fish out the largest individuals to export, then most likely they're female.
You should go back to the store and see for yourself if you have the ability to spot a male. If the markings on the shrimps' bodies are well visible, you should be able to spot non-females if they're there. Otherwise, see if they will catch the smaller individuals for you, which will more likely be males but not necessarily will be.
My second berried female is releasing her babies a bit better than the first. But I may be putting my Amano larva rearing project on hold.... just got another type of shrimp to try the larvae thing with. They've likely taken priority.. how fickle of me, I know.
(It's possible I can do both at the same time though...)
You should go back to the store and see for yourself if you have the ability to spot a male. If the markings on the shrimps' bodies are well visible, you should be able to spot non-females if they're there. Otherwise, see if they will catch the smaller individuals for you, which will more likely be males but not necessarily will be.
My second berried female is releasing her babies a bit better than the first. But I may be putting my Amano larva rearing project on hold.... just got another type of shrimp to try the larvae thing with. They've likely taken priority.. how fickle of me, I know.
(It's possible I can do both at the same time though...)-
chlorophyll
- Shrimp
- Posts: 218
- Joined: Wed Feb 16, 2005 1:22 am
- Location: Hawaii - USA
They're opae kuahiwi or Hawaiian Mountain Shrimp (Atyoida bisulcata). Hawaii's only native stream Atyid shrimp, and badly declined in numbers on my island. I promised some very nice government stream specialists/researchers (who delivered a group of them to me) that I'd keep them informed if I can successfully rear the larvae to PL and do my connected research as planned.
They are actually kind of similar (to me) to Amano shrimp in form and climbing tendacies, but are probably very different in many ways too. (beside the clear fact that they're Atyoida, not Caridina, and they filter feed)
Another poster has some 'Atyoida pilipes' ... apparently closely related and they have similar body markings, but kind of different face and body shape. (the Hawaiian ones are not quite as colorful as the A. pilipes appear to be, either. But I love the bisulcata's anyway!)
viewtopic.php?t=781
On the other hand, my professor became intrigued by the Amano larvae I just had hatch. So I won't be tanking on that project just yet either.
They are actually kind of similar (to me) to Amano shrimp in form and climbing tendacies, but are probably very different in many ways too. (beside the clear fact that they're Atyoida, not Caridina, and they filter feed)
Another poster has some 'Atyoida pilipes' ... apparently closely related and they have similar body markings, but kind of different face and body shape. (the Hawaiian ones are not quite as colorful as the A. pilipes appear to be, either. But I love the bisulcata's anyway!)
viewtopic.php?t=781
On the other hand, my professor became intrigued by the Amano larvae I just had hatch. So I won't be tanking on that project just yet either.