The state Office of Parks, recreation and Historic Preservation says it's lost so many officers to other agencies and retirements that it cannot safely hold the event.
The display had been an annual event for 15 years.
Parks spokesman Dan Keefe says the issue won't be resolved unless more officers are trained. He says there's no decision at this time to hold a police academy class. The last one was in 2008.
In the meantime, the agency is talking to the Department of Environmental Conservation about having its officers help to patrol the parks.