As you all will know some anglo concertinas have two novelty duck type call buttons was this limited to one maker or did other makers have similar .

Definitely not limited to a single maker, since I've had a couple of Lachenals with novelty buttons, but the Wheatstone ledgers also list several. In the Wheatstone ledgers a "cock crow" and "bird whistle" seem to be "standard". On Lachenals I've also run into what I would call "baby cry". Not sure about "duck call". I've heard tell of "dog bark" and "train whistle", but I've never experienced them... on a concertina.

Aw shucks. I thought this was about big buttons you wore. You know, like political badges only with concertinas on them. Oh well.

Or smiley faces?
Before the internet or Post-its, smiley faces on small buttons were a cool thing, and some people would draw them in handwritten letters. But it's the buttons I remember. I think I still have a few in a box.

I have some of the old political buttons, too, but nothing recent.

"Cock crow" and "bird whistle" are the names by which I have long known them, but I think the other names are just different people's attempts to describe the same things. I have seen such buttons mainly on concertinas by Lachenal, but also on ones by Wheatstone, Jeffries and Jones, and not only on anglos, they are sometimes to be seen on Englishes, and also on duets.

I have an old "Gloria" 10-key melodeon that is rather overloaded with novelty effects, not only does it have a cock crow and bird whistle, but also a cuckoo and a vox humana ("tremelodeon") stop.

many thanks for the replys would there have been a time span for this feature?

From the instruments I have seen, I would reckon from about the 1870's up until the 1930's.

They can be used to produce different sound effects, depending on how you move the bellows. Some people simply refer to them as a "whistle" and "squeaker".