Dad eating unfertilized eggs vs eat eating dad.

[Option]

As I'm watching my male PK tend to his nest on day 2, I've noticed that he is still spitting up a large number of eggs into the bubble nest repeatedly. Doing a great job of picking up the eggs that repeated fall day in/day out. But I've also noticed that his belly is much bigger now (he had lost weight from no food during the days of courting prior to the actual spawn) and I can only assume he has eaten some of the eggs during all of his time tending to the nest and falling eggs.

A question that comes to mind is, he is clearly not an egg eater as there are still hundreds of eggs in the nest and he is clearly still picking up and spitting the eggs back into the nest. So I'm curious as he picks up the egg in his mouth, is he able to discriminate whether the egg is infertile (based on a taste or smell) and then proceed by swallowing the infertile eggs vs spitting back up the developing fertile eggs?

[Myates]

He is cleaning the eggs to help prevent fungus from growing :)

I don't know exactly how they can tell, but maybe he can feel movement of the developing fry, or the size, etc..

[indjo]

Not sure how they know, but it seems they do. Often, bettas nowadays prefer small number of eggs/fry. I have lots of these kind of males. But either way you will still end up with lots of fry.

[Option]

So then do we know for sure that it's only the infertile eggs they are swallowing?

[louisvillelady]

We don't know for sure how or why they decide to eat the eggs they do eat if they are not egg eaters. The more you get to know your individual fish, the more you will be able to determine or rather form an opinion of why he is eating certain eggs. I had one dad that always ate most of his eggs. At the same time that I was using him, I changed my breeding practices and started breeding straight in the grow out tanks. This male started leaving what I assume was most of his eggs. His spawns grew from 50-100 fry to 150-200. So I can only assume that he felt he didn't have enough space.

I think the dads know way more about the eggs/fry than we can ever know with out some high powered magnification and extensive education into what it is we are actually looking at. They have to be able to detect fertile eggs from non fertile by taste and possibly movement. When the fry are free swimming, they are just little blackeyes to us, but I'm certain Dad can actually see their development. Just my opinion of course. But I think a good Dad knows best.