Bateman, 19, who was this week handed the number 11 shirt by coach Francis Cummins, injured his shoulder at the end of last season and was told rest would heal the problem, but on resuming contact during pre-season training, the injury flared up again.
He is due to have the reconstruction on Monday, and will be out for 12 weeks.
Meanwhile, Gale will have an ankle operation on Wednesday which will rule him out for eight weeks, which should see him recover in time for the Bulls’ first Super League game against Wakefield on February 3rd.
Cummins said: “It’s really disappointing for both players as well as the club. Pre season training is going very well and to suffer these setbacks is a blow. However it is better to find out now than at the start of the season and both players will be working hard to get back to full fitness as soon as possible.”
Gale, who suffered the injury while playing for England Knights, missed 10 games last season with an injury to his other ankle.
Bateman recently signed a three-year contract extension to keep him at Odsal until 2015.