If flute players are flautists, why don’t tin whistlers have a term?
According to the dictionary, a whistler is someone whistling with their mouth, not an instrument.
Place your suggestions here.
[ Post edited. - Mod ]
My wife has a word for folks who play the tin whistle. And it’s not pennywhistlers.
I just say whistler.
Flageoletist! 
I don’t care what they call me as long as they don’t call me late for supper.
Welcome to the neighborhood.
Feadoggie
Wouldn’t that be “flageoleur”? Or maybe that’s someone who eats beans.
That’s ‘flatulist’! His nickname was Le Pétomane.
Bob
Nope, I seen it in a dictshunary once, don’t ya know.
And it has nothing to do with Opus Dei either.
Mongo like!
Feadoggie
Fipple Flautist
Not so much.
Nancy Toff says in The Flute Book:
"Once a week I’m asked whether I’m a flutist or a flautist. My answer is a vehement “flutist!”
People may call me a fluteplayer, or a fluter, but please don’t call me a flautist (consider the negative connotation: the verb flaut means to jeer or mock).
Since the English ‘flute’ is obviously related to the French, it follows that the player would be ‘flutist’ (the term, in English, dates to 1603).
‘Flautist’ did not appear until 1860 when Nathaniel Hawthorne used it in The Marble Faun."
In short, ‘flautist’ was invented for a poem.
Flute, fluteplayer; whistle, whistleplayer.
Flute, fluter; whistle, whistler.
“Whistler” has been around for centuries. Why reinvent the wheel?
How about “feadogger” or “feadogist”, based on the Irish word for whistle? I think it makes sense, because “flautist” is based on the French word for flute. Or then again, maybe not. It does lend itself to other terms though: feadogism, feadogology, feadogaphobia.
Whistlist. 
Sigh. Someone has to be the damn pedant around here, so it falls on me. It’s spelled “flout”, and in our time it means to defy, refuse to comply, treat with disdain. Of course it implies contempt, but one doesn’t flout a person; one flouts convention, rules, fashion, desires, common sense. Like that. It’s much more than just merely making fun of something; it’s contravening behavior or opinion.
Pedantry is just an excuse to flaunt your knowledge. 
I agree with some on here I have always referred to myself as a Fluter, never a flutist or flautist and have always called those who have a love of shrill dog whistles, weak arms and small hands “whistlers”.
Ha. I see what you did there. Points to those who get StevieJ’s veiled admonition.
If every whistlist has a whistle wishlist, for how many whistles would a whistlist wish?
Feadoggie
Where do you live? I have a few friends that would like to stop by later today.
Feadoggie
Okay, just to give pancelticpiper his due: “flout” indeed used to mean to mock or jeer. But it’s an archaic meaning that has fallen out of use, and would sound strange and wrong according to modern convention. But it’s a convention, so feel free to flout it. If you get converts, you can flaunt them.
Thank you.
Pedantohedron
I’m a might partial to “whistleblower” myself . . . although that might be trademarked.
Anybody have Ed Snowden’s number?
Well, whistlepig has been mentioned around the forum before so I’m proud to be oinking all day long! Groundhog - Wikipedia
And I’m confident that I’m not the only one.
You’ve all been oinked! 
Or Deliverance 1972 