Hello XXXXXX, I hope there haven't been any more losses to your aviary. Have you got nest boxes in the enclosure ?
Any climate control methods at all ?
XXXXXX, if these birds were hatched in this climate and always outside, they may be able to handle it; however, it sounds like pretty extreme temps for even a more hardy variety.
Heated perches may have their benefit, but more extensive modifications need to be made to outdoor aviaries for weather like this and even summers.
Not just nest boxes that they actually use, but the ability to cover the aviary and shelter them from winds, rain, snow. An outdoor heating method - in an aviary, electric is safest to avoid toxic fumes - should be considered, but it has to be safe from shorting itself out or starting a fire.
Summertime temp modifications would include partial covering of the top and a side for shade opportunity all times of day and shelter from rain if any bird decides not to use a nest box.
A misting system helps cool the surrounding air down in particularly sweltering temps.
At this point it would be my choice to bring them inside for the entire season and work on making their aviary more climate controlled.
They should also be vet checked for any disease that this might be. That is a very prudent move given that you've lost multiples. It would be ideal if you found a vet to come to you and double check your aviary.
If you can't find one, then take one or two of the survivors in for a genetic/DNA blood screening for the more common diseases as the vet feels warranted in your particular area.
Let me know how you do - I'll try to support you all the way on this ok?
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