"We (permanent staff) are few," an official at one Amazon park, who asked not to be named, told Reuters.
As of Friday morning, 22 contracts for personnel for working on the national parks agency's Amazon reserves had been published via Colombia's national contracting agency.
Last year, at least 107 contractors had deals for work on Amazon reserves by January, data from the agency seen by Reuters showed.
The government of leftist President Gustavo Petro, who took office seven months ago and has pledged to lower deforestation, plans to initially replace annual contracts for national parks workers with four-year.
Five would-be park workers told Reuters the delays meant they had been forced to find other jobs.