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Just curious if isopods will eat frog eggs? I've noticed that they will eat their dead... Just curious if that's a concern??
no, tads are deposited in water, eggs usually on surfaces like brom leaves ,film canisters, ectDont most darts lay their eggs in small pools of water like broms? If so they are perfectly safe from the iso's. Isos are crazy little buggers, i've seen them take down a like eurycantha nymph lol
I have significant doubts that the frogs can damage eggs (particularly newly deposited eggs) by "stomping".... There are a number of descriptions of the resilence of anuran eggs in the literature that include picking them up individually with forceps and squeezing them (see (not free) Xenopus laevis In Vitro Fertilization and Natural Mating Methods) The vitelline membrane of anuran eggs is surprisingly resilent to pressure and while it may allow deformation, it has been shown to withstand up to 5 atmospheres in pressure so the idea that a dendrobatid "can stomp" eggs into being non-viable is at direct odds with the tests in the literature.If the eggs got stomped instead of eaten, or there was anything left over in them I could see the isos going to town! I've rarely ever caught frogs in the act of eating or stomping eggs... I can think of only 3 cases over 13 years... and one of those was an anthonyi and they are so bold that almost doesn't count LOL. This is one of those things that is not "aggression" directed at another animal, but something they do to reduce reproductive competition (wanting that male to take care of HER eggs, or limited tadpole sites so reducing competition for HER tadpoles). Not saying that's the case, but I'd believe that before isos eating eggs. I'm not even sure they can get through the gel without it already having degraded. Degraded gel that is hosting fungus and debris? Iso buffet!
Another theory of egg eating - stress. Either being in the tank in general or messing with laying spots.
If the eggs got stomped instead of eaten, or there was anything left over in them I could see the isos going to town! I've rarely ever caught frogs in the act of eating or stomping eggs... I can think of only 3 cases over 13 years... and one of those was an anthonyi and they are so bold that almost doesn't count LOL. This is one of those things that is not "aggression" directed at another animal, but something they do to reduce reproductive competition (wanting that male to take care of HER eggs, or limited tadpole sites so reducing competition for HER tadpoles). Not saying that's the case, but I'd believe that before isos eating eggs. I'm not even sure they can get through the gel without it already having degraded. Degraded gel that is hosting fungus and debris? Iso buffet!
Another theory of egg eating - stress. Either being in the tank in general or messing with laying spots.
I had a couple of Varadero eggs/tads that were ready to be transported. I was lucky enough to be in the right place at the right time. I witnessed the male stomping the tad like crazy to finish breaking him loose from the gel. It took a lot of stomping. I was surprised at how rough he was being with them but they were fine. I think they may be in Zookeeper Doug's collection now.I have significant doubts that the frogs can damage eggs (particularly newly deposited eggs) by "stomping".... There are a number of descriptions of the resilence of anuran eggs in the literature that include picking them up individually with forceps and squeezing them (see (not free) Xenopus laevis In Vitro Fertilization and Natural Mating Methods) The vitelline membrane of anuran eggs is surprisingly resilent to pressure and while it may allow deformation, it has been shown to withstand up to 5 atmospheres in pressure so the idea that a dendrobatid "can stomp" eggs into being non-viable is at direct odds with the tests in the literature.
Ed
I have significant doubts that the frogs can damage eggs (particularly newly deposited eggs) by "stomping".... There are a number of descriptions of the resilence of anuran eggs in the literature that include picking them up individually with forceps and squeezing them (see (not free) Xenopus laevis In Vitro Fertilization and Natural Mating Methods) The vitelline membrane of anuran eggs is surprisingly resilent to pressure and while it may allow deformation, it has been shown to withstand up to 5 atmospheres in pressure so the idea that a dendrobatid "can stomp" eggs into being non-viable is at direct odds with the tests in the literature.
Ed
I have some significant skeptism that we are correctly interpreting this behavior as well... It takes less than ten minutes a day for a male in the wild to wet the eggs (which could in part account for a lack of observations of it), but the behavior often described as "stomping" is the same behaviors that males engage in when wetting the eggs. Given that this behavior begins with deposition, I'm suspicious that "stomping" to get the tadpoles out of the egg is a correct interpretation. The assistence to the tadpoles may simply be incidental to wetting the eggs... If the tadpoles actually required assistence to escape the egg, we should see more issues with artificial rearing...I had a couple of Varadero eggs/tads that were ready to be transported. I was lucky enough to be in the right place at the right time. I witnessed the male stomping the tad like crazy to finish breaking him loose from the gel. It took a lot of stomping. I was surprised at how rough he was being with them but they were fine. I think they may be in Zookeeper Doug's collection now.
Infertile eggs behave and look this way. They don't undergo the rotation in which the "vegetal pole" ends up on the bottom which leaves you with the yolk distribution which can look like they are swirled.G
So the situation is this... eggs usually 48 hours old or under, and when you pull the eggs they are not those tight round little spheres, but rather look like a little slurry from a blender injected into the gel. They are usually gray like infertile eggs would be in color, but I usually saw shades of gray swirled, much like if you were dealing with eggs that hadn't solidly turned one solid color yet (expected given the age of the eggs) and ran through a spin art machine. I usually saw this in female heavy tanks (mostly recently I had this often with a group of 1.3 auratus) the future.
OK, I'll buy that. I didn't stick around long enough to see the whole thing as I didn't want to interrupt him. The next morning one had been transported and I simply assumed.I have some significant skeptism that we are correctly interpreting this behavior as well... It takes less than ten minutes a day for a male in the wild to wet the eggs (which could in part account for a lack of observations of it), but the behavior often described as "stomping" is the same behaviors that males engage in when wetting the eggs. Given that this behavior begins with deposition, I'm suspicious that "stomping" to get the tadpoles out of the egg is a correct interpretation. The assistence to the tadpoles may simply be incidental to wetting the eggs... If the tadpoles actually required assistence to escape the egg, we should see more issues with artificial rearing...
Ed
OK, I'll buy that. I didn't stick around long enough to see the whole thing as I didn't want to interrupt him. The next morning one had been transported and I simply assumed.