What can I do keep morning doves off my deck I have dropping all Over?

https://www.youtube.com/watch?v=jcJDjcYp58Y

Roofers use rubber snakes to keep birds from picking at them. They're cheap and commonly available at discount stores and WalMart/KMart. Get a couple and place them strategically around your patio. Move them occasionally so the birds continue to think they're actual snakes.

Also the statue owls are really great for warding off quite a few "mess makers"

Our town has walking mall with the usual pigeon population. Many of the shops on the mall have fake, life-sized owls which seem to control the pigeon numbers, especially when they're moved on occasion. (I would think this would work for doves as they are related to doves.)

I purchased a fake owl to keep the birds out of my garden. Six weeks into it and it's working great. Way less birds for me. Good luck.