Hairy vs Downy?

Today's photo and text are by J:


When we lived in Toronto we frequently had black and white woodpeckers at our bird feeder.  They were indistinguishable by their plumage.  The larger ones were Hairy Woodpeckers and the smaller ones were Downy Woodpeckers.  Size alone was not enough to distinguish one from the other without additional context.  
 
After further research, I learned that Hairies are jackhammers and Downies weedle their way into the bark.  As a result,  Haries have short, thick beaks with a length about half the diameters of their heads, and downies have long needle-like ones about the same length as their head 
 
Along the quai under the Cité de la mode in the eastern end of the Seine within Paris there is an colonnade that has become a centre for Parisian street art.  
 
I took dozens of pictures today along the quai.  This is clearly a hairy woodpecker.  If you are my friend on FB, I have posted a bunch more photos there.  Any ichtiologists care to help me identify some fish?