cant keep duck, what to do? help!

My bf came home with a duck during Easter time bc this lol black chick was being picked on... It's been 3 months now, ducky is big,quacks a lot and getting a little too much to handle for us :( ducky is always innthe backyard with other dog kodak ( they get along) he's free to fly away whenever but just remains at our place...I feel bad that it must be very lonely, and not the best to be stuck in our back yard. My bf wants to drop him off to our local nice big park with other ducks but is that gonna help? Or should we turn it into our local animal shelter for farm use.... Please let me know what you think :)
   
thx!!