That would not go down well in Nottingham, where everyone is a duck, as in ay oop mi dook. 
Nevertheless, I would love to know the backstory to that. 
So would I; I just saw it on Facebook.
Hey Claude, make me a picture of a duck standing by a door, with a sign on the door that saysâŚ
I suspect.
I donât know why but that place looks like Blackpool
I might have to pull the discussion to another thread. But, yes, I have my suspicions as well. For one thing the tape goes over the corners of the sign and the natural thing for the shop owner to do would be to tape the sign to the inside of the window so, from the outside, youâd see a gap in the tape. The reflection (or lack of) suggests that the sign is on the outside of the door though.
Also the sign is identical to this photo
Alternatively there is a bloke going around with a sign and a duck, taking amusing âDo NOT let the duck inâ photos.
But then, thereâs this photoâŚ
A meme in the makingâŚ
Itâs raining.
Which is why @billybutcher might, I say might, have the wrong end of the stick if there is an awning, the windows in each case are dry. But I agree, the multiplication is suspicious although wouldnât the duck prefer to be outside, nice weather for ducks etc.. 
I vote for genuine - the two signs are not identical, though may have been written by the duckâs owner. Duck is double underlined in one, not in the other.
Right, this debate is getting a bit long winded for the humour thread.
That one looks more obviously AI - there is a reflection of the duck in the window so the sign is on the inside, yet we see the duck (see what was done there) tape on the side of the sign facing us.
For the first two images the sign is identical, right down to the fact that the middle of the cardboard has a rough edge
from the first image
and
from the second.
The fold in the board also runs through the O of âDOâ identically as well.
Which, as I said, suggests there might be someone going around with a sign and a duck, taking photos. The reflected legs of the photographer also look similar.
Spoiler alert: hereâs Googleâs explanationâŚ
The phrase âdo not let the duck inâ is a common, humorous internet meme often paired with images of ducks attempting to enter homes or looking ominous, symbolizing a chaotic or chaotic-neutral entity that, if allowed entry, will cause mayhem. It is often a humorous take on preventing a âMilkshake Duckâ scenario.
- Origin Context: It stems from general internet meme culture highlighting that ducks, while cute, can be unruly, messy, or aggressive creatures if they enter a human-occupied space.
- âMilkshake Duckâ Association: It is frequently used in reference to the âMilkshake Duckâ phenomenon, a term coined by Twitter user @pixelatedboat in 2016. This term describes a person who becomes popular online, only for their dark past to be revealed shortly after, ruining their reputation.
- The Meme Concept: The phrase represents a plea for caution, suggesting that allowing the âduckâ (the seemingly innocent or entertaining trend/person) in (into the spotlight) will inevitably lead to regret.
Youâre all quackers
Personally I think the duck just wanted to get out of the fowl weather.
Itâs a shame we donât have a âgroanâ emoji. 
It must have refused to pick up the bill.
The angle of the photos would not allow the photographers legs to be seen. The small variations while retaining key features point very strongly to a synthetic image.
Just trying to weed out the fakes. 
Itâs getting harder.
Generated with Firefly in Photoshop, using one of the existing duck images as a reference - I had to copy and paste the sign across as AI canât do text properly.
I canât help feeling the duck should be getting royalties.
Whoever took the original duck photo should.
At least with Adobe Firefly we photographers get a fee for allowing our stock photos to be used by Firefly for generative images.