Open mouth breathing in canaries could mean a number of things but probably not that he's dim-witted.
If you've watched the TV series "Stranger Things" on Netflix, you may remember hearing the term "Mouth Breather".
It's meant as an insult to someone who's not too bright. (It's a great show by the way, I highly recommend it.)
But with our canaries, "Mouth Breather" has a completely different meaning AND can be a bad sign something is wrong with our bird's health.
Below is a short section of the LISTENING report ...
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....8. A healthy canary breaths with his mouth closed.
Open Mouth Breathing In Canaries
Your canary will breathe with an open mouth if he is excessively stressed. Such as when he is held by you or aggravated by an unruly cat.
I currently have a cat (who now stays outside, by the way) who, when he was a kitten, would jump on top of the cage trying to get at my poor house canary. He stressed my canary out enough that the bird would breathe with his mouth open for a minute or two.
And me too! Especially after chasing that cat around the house with a broom!
And your canary normally breaths quickly but watch for excessively rapid breathing. This might be a sign of air sac mites or a respiratory infection.
Open mouth breathing in canaries or panting can also be caused by overheating. Another sign of overheating is wings spread open while standing on his perch...."
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You also might see open mouth breathing in canaries accompanied by listlessness and puffiness, like this...
And you might hear clicking sounds too.
There's a lot more info in the LISTENING report.
In fact, it covers 27 symptoms that every canary owner MUST KNOW how to watch for PLUS discusses how your canary bird's body language is "speaking to you".
Don't be a mouth breather,
Darren :)