I am sorry you lost some of your eggs! You probably know most of the ideas I toss out, but I might have something that will click as a reason... In my experience, Zebras tend to be excellent parents (never had a pair that didn't breed abundantly!) as long as they have the right nutrition. Many will risk their own health to raise their babies. So I bet you will have success soon. Here are a few thoughts on what may have occurred or is occurring to cause egg loss:
(1.) The eggs are infertile:
It is pretty common for any female finch to lay infertile eggs, sit on them, and then either abandon that nest or they throw away/eat the eggs. When they are incubating their eggs, they roll them and move them - stimulating the baby inside to grow. If there isn't a baby, then they will eventually have to get the infertile eggs out of the way to make room for the fertile ones. The lack of motion within the egg eventually will signal most finches to discard the eggs.
Depending on your Zebras' dispositions, you may be able to safely check the remaining eggs for signs of life without the finches abandoning the nest. Your scent is on all around them, so they are not likely to be overly anxious if you check the nest and even handle the eggs a couple of times. (I check my Blue Cap Cordons and Society eggs weekly and have to move the Cordon eggs to the Society nest preferably before they hatch.)
(2.) Privacy and Number of nests/nesting spots:
The finches I have owned have shown themselves to be great little carpenters and I try to provide at least two or three extra nests plus hiding places (fake plants) where they can build their own nests. Perhaps your Zebras will relocate because something about the current nest or its location is not to their liking? I don't know if you use cages or an aviary for your Zebras, but I have never met a pair that didn't build a nest wherever they could. (Food bowls often get used!)
My Blue Cap Cordons really like privacy and actually avoid the prebuilt nests. They make their own in the plastic/silk plants near a ceramic heat emitter I placed above the cage. My Societies, who are more like your Zebras in temperament, have shown interest in only one nest in their cage.
(3.) Calcium Deficiency & Cracked Eggs
Its not unusual for an egg to crack and leak into the nest and the parents will sometimes abandon a nest and/or eat the egg shell. With infertile eggs, you may find that they eat them even if they are not cracked. The female needs alot of calcium when making those eggs, so its vital to provide that extra boost of calcium in abundance through cuttlebone or crushed oyster shells. Calcium deficient females will eat their own eggs' shells for survival purposes. They will also lay eggs with thin shells more prone to breaking.
I have had the best results with the oyster shells for my Cordons as they are very soft-billed compared to Zebras. When I bred Zebras, cuttlebone seemed to be sufficient and they bred like rabbits.
Checking Your Eggs for Fertility:
If you hold an egg up with a light in the background, you can see if something seems to be in there. Yellow yolk should not be the primary color after a week or so. Sometimes, when the eggs have been kept very warm, its hard to determine if there is a baby or just that the yellow yolk has kinda gotten brown and more gel-like. I usually return any egg when in doubt. The yolks I will usually toss. I try to do this as quickly as I can (while being gentle of course! LOL) in order to keep stress levels low as possible for the parents looking for their missing eggs and/or nest. Once I am convinced there could be a baby inside, I stop checking. If it hasn't hatched after the birds are actively incubating it for around 3-4 weeks, it probably was just an infertile egg that turned brown inside.
Zebras are protective but not paranoid. In general, I have found they are not too quick to abandon their nests like the African Waxbills, and will allow a few checks on the eggs without getting too stressed. Of course, every pair is different.
I hope something in all that turns out to be helpful! I hope the remaining 2 eggs hatch and survive! If I can help ya with any info, feel free to email me at [email]skgserenity@aol.com.<br[/email] />
Shannon
(skgserenity@aol.com)
P.S. If none of this makes sense its cuz I writing it at 3:30am and in the middle of mega sleep deprevation!!!
