How to tell if eggs are fertile

[Kholbrook1]

I have two society finches that have laid eggs two times now. I’m not sure on their genders. First clutch had 9 eggs, all ended up not being fertile and I disposed of them after 4 or 5 weeks of waiting. With this clutch there are 11. We’ve been going on 4 weeks now and nothing has changed. I took them out (carefully) and checked with a light. Some look like they might be fertile but I didn’t see any red veins in any. I tried them in warm water to see if I could see any bob. Three actually sunk and those are ones that I thought may have something. The rest floated but didn’t bob, one completely floated on top so I think that one is definitely dead or non fertile. So my question is, how do I really know when to dispose of them or if I should wait another week? They kind of look like they may be starting to form red veins but they are already 4 weeks old. Is that normal? I’m new to all of this but have done some research on what to look for. I don’t want the eggs to rot in their nest. I think I may have two females because their clutch is so large. What are peoples insites?

 

[Zara]

Welcome to the Avenue,

First, it´s not a good idea to put any eggs in water. It can drown the eggs if they are fertile.

how do I really know when to dispose of them

Once the average incubation period is up, give it a few extra days to be on the safe side, then remove them. I do not know how many days this will be for society finches but Google says it is 14 days (hopefully another member can confirm that). So I would never keep eggs more than 21 days after brooding starts.

I think I may have two females because their clutch is so large.

Try separating the birds for a while, see if they lay?

 

[finchly]

If you want the eggs to hatch, please don’t handle them much. The oils from your fingers can transfer to them.

And as Zara said- don’t put them in water!

11 is a big clutch. It does sound like you have 2 hens. But I had a clutch of 10 awhile back so it’s not unheard of.

 

[Mizzely]

I am not a finch expert either, but I did find this image on Google for candling finch eggs:



And this video seemed to be really informative! It does say you should wait at least day 5 to candle to prevent harming the developing embryo.

 

[Kholbrook1]

Thank you everyone! I only handle them once, and when it’s been way over 14 days. I checked with a light and the first time around none had embryos so I threw them out. I was going to do the same with these but it looks like some have embryos, like the first image of the freshly laid egg. Some of them look like image 3, 3rd day of incubation. Pretty much like image 4, early embryo death but the whole egg isn’t yellow still has white. I didn’t want to dispose of them if they were alive so I put them back in their nest. The birds are still sitting on them thank goodness!

Do birds lay a new clutch if there is one clutch already in the nest? Could that have happened? Maybe that could be why some look to have freshly layed embryo?

i read that you can also check for alive eggs by the way they bob in the water. Is that not recommended anymore?

 

[Mizzely]

The only water test I have seen is for seeing if eggs are fresh before you eat them.

It i definitely possible for them to lay more than one clutch, especially if the 1st clutch did not hatch. Or you have two females, and one laid much later than the first. So it i very possible that you could have duds mixed in with embryos.

 

[finchly]

Yes they can and will lay more eggs. But if you’re in there doing things like messing with the eggs and putting them in water, you were in a big chance of them abandoning the eggs. I don’t know if people are recommending water or not – I just would never do such a thing. Egg shells are very permeable and water could get in there, even if you have lotion on your hands or something it can affect an egg. I can’t stress this enough.

Society finches are usually great with their eggs. Just leave the clutch alone and they will raise a great bunch of babies for you.

Hete are my most recent rascals, errr, society finches.

 

[finchly]

PS see in the photo that one baby is much younger than the others? Lol it’s most likely from another hen.

 

[RatKave]

There will normally be development by 5 days of incubation. If you are sure they are not alive (after 10+ days) you can open them and check the yolk for a white bulls eye. If there is none they were not fertilized. If there is, but no development It could mean they died or was never viable. If you get consistent pattern of no bulls eye you most likely have two females. (They may just not be breeding.) I have had females who lay together, and rotate incubation while the other eats.