Cracked Eggs Need Careful Decisions
From Gia written with permission
I was checking a nest this evening, and I removed it from the nestbox...five lovely eggs. As I was putting it back in, the side of the nestbox that opens for monitoring came down (gently) and nudged one of the eggs. It was enough to crack it (I feel terrible!), but the crack seems to be only in the outer layer of the egg and did not pierce all the way through.
Unsure of what to do, I left the egg. Based on what Linda Violett mentioned in an earlier message, eggs pierced by wrens that have drippings need to be immediately removed, but looking at this egg, I think it might be ok? But I don't know what will happen once it is rolled around etc., by mom. I also thought that I remembered reading about someone on the list who found eggs that had been pecked by wrens, but at least one wasn't badly damaged and the chick hatched?
Any advice is appreciated. Of course I will keep an eye on it, and of course I will be MUCH more careful.
From Keith Kridler written with permission:
Keith Kridler Mt. Pleasant, Texas
Linda Violett mentions repairing the cracked egg with finger nail polish. A LOT of web sites report using this. I have NOT seen % wise how successful these patch jobs are. Normally these repairs are done on VERY rare parrots laying eggs in captivity where the eggs will go into incubators and NOT go back under the hens.
Below is a link to the first webpage that pulled up with a Google search on "repairing cracked eggs". If you read this repair procedure you will see how involved it is to repair an egg! You already learned that simply brushing a bluebird egg with the door of the nestbox or simply touching them with a long fingernail can do the same thing!
NOW you would have to remove the nest, search for the damaged egg. Remove it and replace the nest while you haul this egg to the kitchen table to work on it. Do the repairs let the patch dry and then haul the egg back to the nestbox. Then again remove the nest and eggs and replace the egg all because you damaged one egg by removing the nest once just to LOOK at it:-))
Egg shells protect the membrane of the egg from damage. The membrane protects the contents of the egg from bacteria and other pathogens. BOTH of these protective layers regulate water loss from the developing embryo but they need to breath or allow Oxygen to enter through them to the developing chick and also to allow the build up of Carbon Dioxide to escape.
Covering too much of the shell with any product will cut down that percentage wise of the breathing area of the egg! Again these egg shells allow air and oil flow through the shells. Take a good whiff of fingernail polish and remember that this is what the developing chick will be exposed to till the product dries. A skin will form on the outside of the coating of fingernail polish and the rest or at least part of the volatiles will be forced to go through the porous shell and into the embryo.
We sometimes need to learn from our mistakes and QUIT while we are only ONE dead egg behind! I see little chance of me being able to do a good patch job and a GOOD chance of losing one of more of the remaining four eggs!
This to me is where it would not hurt us to intentionally damage or dent some House Sparrow eggs and then we could ALL practice on doing repair jobs with various products to see what works the best or how much area of the sparrow eggs you could cover with fingernail polish and expect the eggs to hatch. The link below is to the copied text below that. KK
Repairing Cracked Eggs
Published in Bird Breeder Magazine, Breeder Q & A, February1996
� 1996 Howard Voren
The contents of this web page, including all text and photographs are copyrighted material. No part of this page may be reproduced, in whole or part, without the express permission of the author, PO Box 152, Loxahatchee, FL 33470
Q: We occasionally need to repair eggs that have been damaged. We have sought advice as to what materials to use to make these repairs. It seems that everyone we talk to recommends something else. What do you recommend?
A:Although there are many things that can be used with equal success, I use simple Elmer's Glue-All�. If I am dealing with fine hairline cracks, I will "paint" a very thin layer of glue over the crack. If I am dealing with a break that has caused an indentation in the shell, I will use a single ply of facial tissue as a support webbing over which to paint the glue. Many times, as the glue dries, the weight of it will force the indentation to extend further in the egg. The tissue acts as a support to help prevent this.
The easiest way to proceed is to first cut a piece of tissue that is shaped like, but a little bigger than, the indentation. Then separate the two plies, and place one over the indentation. Paint the edges with a thin layer of glue. The glue that seeps through the tissue should be enough to make the overlap stick to the edges of the indentation. Once this is done, paint the rest of the tissue with glue to create an airtight seal. If I am not satisfied with how well it sticks, I will paint more glue around the edges of the tissue. If I am not happy with the strength of the tissue webbing, I will place the second ply on top of the first piece. The existing glue should be sufficient to make the second ply stick to the first.
The main problem that occurs with repaired eggs that are not killed by the trauma or contamination is extreme water loss. Many aviculturists use different repair materials and glue compounds because they believe that what they use will prevent water loss better than those that they have tried previously. I personally believe that success rate is more of a function of the number of hairline cracks that you do not see, rather than one type of material being much better than the next. Eggs with several unnoticed hairline cracks that go unrepaired will most certainly experience a greater water loss than those that have no "hidden faults." On the other hand, if you cover the egg too extensively with repair material, it will not allow the necessary water loss to take place. This, of course, will also result in the death of the embryo. I have never saved a damaged egg that has been damaged to the point that fluid has leaked out of it.
From Paula Z written with permission:
Good information, Keith. I have never damaged an egg of a native cavity nester, but if I accidentally did, I would probably remove the egg. If a damaged egg remains in the nest, its likelihood of remaining viable would be small AND that damaged egg could leak its contents onto the other eggs, making the nonviable as well.
I have opened nestboxes that have had eggs damaged by HOSP. What often happens is, even though some of the other eggs were not damaged, the albumen and/or yolk from the damaged egg sort of glues them in the nest, making them impossible for mother bird to turn and probably blocking the pores of the once viable egg shells, thereby ruining entire clutch.
Powell (Central) Ohio
Response from Gia:
Thanks everyone for responses and good information. I had already decided not to do the nail polish. I haven't used it for years (on myself), and I don't think the fumes in the nestbox would be a good idea at all. Based on Paula's advice, I am going over right now to remove the egg. Now, if only I could apologize to the mom.
MORE FROM GIA:
The depths of my inexperience/stupidity are immeasurable.
Here is what just happened:
I went over to my neighbor's nestbox to remove the "cracked egg" that I e-mailed about this morning. I did ever-so-carefully remove the nest because I thought this would be safer than using the mirror and feeling around with my fingers without really being able to see. Upon visual inspection, I saw that all five eggs had small cracks/fissures. I was heartbroken, and I really couldn't believe that the slight touch of the door of the house yesterday could have caused this. I removed the two eggs that looked the worst and brought them home. Then I cried.
Then I checked Bet's website to see if this could possibly be house wren damage. Then I inspected the two eggs I had removed. Upon gently touching one, it split apart, and there was a moving baby bird!
I left the egg split but intact around the baby and raced across the street to the nestbox and placed both eggs gently inside.
I knew that these eggs were at least a week old, but beyond that, I didn't know because it was my neighbor's, and when I first inspected it, there were five eggs. So, the cracking is the eggs hatching (which most people who hadn't been lobotmozied would have figured out), and I HOPE with all my heart that the little baby whose egg I cracked is ready to come out based on the fact all the other eggs are beginning to crack/hatch. The two eggs were out of the nest for probably 15 minutes, and once that egg cracked, it was back in the nest within one to two minutes...It is also a warm, dry day here...
In hindsight, I don't think that the door of the box coming down did anything to egg, but that happening and then me looking down to see the crack just caused me to assume...
Well, I am ready for all comments. I am sure there will be some criticism (deservedly), but man am I hoping for a good outcome on this one!
Comments from Evelyn:
An update from Gia tells me that the baby hatched from the egg that she thought she had broken. She said she’ll let us know if any of the other four hatch.
I have stated before that handling eggs is a most tedious and stressful thing. I just don’t do it unless it is absolutely necessary. They are so easy to break. If I should ever decide to do a repair, I would not do it unless I was sure how old the egg was and also scoop it up with a teaspoon and work on it in the spoon. You would have to make absolutely sure it was dry before returning it to the nest.
Breaking an egg in a nest with the others can be worse than just leaving it be.
Gia really beat upon herself and that is a normal thing to do when there true dedication. She is brave to write about her mistake and she learned from it and hopes others will. We learn early and fast most times that there’s heartbreak that goes with it!