Looks like they are using a sup though 
http://www.shockmansion.com/2013/06/02/video-meanwhile-in-australia-son-takes-his-paralyzed-mother-surfing-by-duck-taping-her-to-his-back/
www.seabreeze.com.au/forums/Stand-Up-Paddle/SUP/Must-see-Duct-tape-surfing/
(edit) I noticed the SUP, that's still a good effort regardless of the board...and I don't think that's her son either.
I definitely see and advertisment for the duct tape coming up with captions like ???????
Don,t leave home without her!!!
In a sticky situation you can always turn to mum...
Mums always there when you need her.........
Sorry could n,t help myself 
Its great what this guy has done....
For sure.....must need her to have a whole lot of trust in the person she is duct taped to
