Starting Monday, 42 California Men’s Colony correctional officers will be temporarily transferred to prisons elsewhere in the state in need of staffing, in the wake of a mandated drop in the inmate population here.

The move is part of an ongoing effort by the California Department of Corrections and Rehabilitation to juggle staffing at prisons statewide amid a budget crunch and the implementation of realignment legislation that has sent nonviolent offenders to county jails.

But the cuts to staffing, including a planned level of 100 officers by the end of the year at CMC, are causing concern among prison staff.

“Safety is the main issue that’s making me stay up at night worrying if I’ll have to visit someone in the hospital because we don’t have the proper security in place,” said Herschel Keel, the president of CMC’s chapter of the California Correctional Peace Officers Association.

The state has transferred some employees permanently from facilities where officials feel staffing is at a surplus to others where vacancies exist. The temporary transfer program is meant as a stopgap measure that will allow workers to return to their permanent institutions.

Those starting temporary work Monday at state prisons such as Corcoran, Chowchilla and Pelican Bay have a right to return to CMC after 60 days, Keel said.

But already, more than 30 correctional officers have permanently transferred from the prison and more could be forced to relocate, Keel said.

CMC plans to reduce the number of correctional officers to 680 by the end of the year compared with about 770 now. The cuts could come through attrition, transfers, fewer hours for on-call officers and possibly layoffs — which the prison has avoided thus far for officers.

“I think that’s a really fast timeline for something like this,” Keel said. “I think people need to keep in mind that many of these guys committed heinous crimes to get in here.”

CMC’s spokesman could not be reached to comment Friday.

But state prison spokes-man Jeffery Callison said that it’s common sense to adjust staffing as California officials relieve overcrowding at state prisons.

“Security of the institutions is our No. 1 priority,” Callison said. “We owe it to the people of California to keep people safe and reduce overcrowded prisons. It’s common sense that if inmate numbers drop, staffing drops.”

A tally showed that the CMC had 5,397 inmates on July 11 compared with 6,216 in September 2011, shortly before the implementation of the AB 109 legislation that transitioned many nonviolent offenders from state custody to county jails.

Statewide, in the same time frame, the total population of inmates in California’s 33 prisons dropped to 120,628 from 144,138.