Space won't be at a premium in northern jockeys' rooms between now and the end of the season.
Michael Coleman is the latest to join the list of senior riders who are unlikely to be in action again in the current racing season, which concludes at the end of July.
The 47-year-old, who rode his 2000th New Zealand winner in August Edition on his home track at Matamata last month, recently underwent successful knee surgery.
"I had some repair work done and I'll probably take the rest of the season off," Coleman said. "That may change, but at this stage I'm not in any hurry to get back."
Opie Bosson, Craig Grylls, Leith Innes and Jason Waddell are other senior northern jockeys who will be absent until the 2017-18 season.