Found indian ringneck hissing

[Sof11]

Hi!

I found an Indian RingNeck Lutino a few months ago. It was being attacked by 3 magpies so we chased them off and saved it. We could not find it's owner after 2 weeks of looking so we kept it. It was very hungry when we found it but a stunning bird! It is not hand-tamed though and we are not sure if it's wings are clipped (We are still in the process of building a bigger split avery - we already have budgies and cockatiels in an avery but do not want to mix them due to stories of IRN's biting budgies feet off… So when it is done we will know). It has taken a long time to get this shy bird to trust me (which is completely understandable). When I used to walk up to its cage it scurries over to the other side of the cage and climbs around the cage (although it's eyes do not pin). It's current cage is not big enough for it to fly in but it does fly a bit (when spooked). My dog who likes jumping up on our bird cages also does not help… Now though if I keep the dog inside it comes up to me when I whistle! Progress!
My problem is we have no idea how old it is. We had assumed it was a female as it does not have a ring on it's neck but if it is younger than 2 it could be a male. It's tail feathers are very long but all that tells me (from what I have researched) is that it is older than 6 months.
Yesterday though, (as I have said it is not hand tamed) when I was putting fresh carrot in its cage, it hissed at me (it has developed a love of carrot which it did not like when we first found it!). It was only once and I thought I had misheard (Ironically I found a cat sneaking around my yard latter that evening). However today when I put more fruit in its cage it hissed at me twice. It was standing meekly over on the other side of the cage but it was hissing at me. I googled it and saw that it is related to a stage they go through. I couldn't find anything about whether they hiss at other stages of their life or not…
I am not sure if this is relevant but it was also yawning a lot when I was whistling to it this morning.
We have had it for months and I haven't heard it do this before so does this mean it is less than 2 years old? Or can they hiss at any age?

Thank you in advance for your help!

Sof.

[AJPeter]

I cannot be much help but perhaps the hissing is saying "Not fruit again?" My Bird Billie won't eat pellet food and is very fussy over her seeds but she also yawns, l thought that she had some stuck in her throat but it is just something they do.
Any ways welcome to IRN
AJPeter

[Doodlebug]

Hi Sof, I'm afraid I can't really help with answering what age they hiss or if both sexes hiss, but mine does this too at times (I'm sure he's a boy as he does the male wing display thing but he is unsexed so don't know for sure)

If he is feeling particularly aggressive he makes a sort of hiss noise, the sound of air coming out through his nostrils and beak when he lunges, or just warning off, that sort of thing? I did wonder myself if it was a female thing to hiss but I'm still unsure of this. Mine is almost 8 months old now but he did it from quite young.

[AJPeter]

Billie does not hiss Doodlebug, even when she lunges so is your bird a male? Is it only males who hiss?
AJPeter

[xxsalxx786]

My bird hisses at me when I try yo touch its wing

[sanjays mummi]

They yawn to "pop" their ears, apparently.