The services' chief officer Andrew Stark, who will depart for an interstate role in mid-February, said some stations have had surplus applications with more than 500 volunteers signed up across the territory.

"Our membership here in the ACT is stronger than ever and we tend to take on recruits in the cooler months so we can train them for summer," he said.

Like most volunteer organisations there are some people who are there when you need them and then there are those who are the core of the organisation, who are there giving so much to the community."

Mr Stark said volunteers had a range of motivations for joining the service with many leaving after a year or two due to professional commitments.

"Some come to us because they want to give back to the community while others just want to pick up practical skills, like driving a truck or swinging chainsaws," he said.

"Some people also want the sense of teamwork and morale that comes with being with people who share your motivations."

It has been a relatively quiet season for Canberra based bushfires with the exception of bushfires at Mount Clear and Mount Taylor in mid-December.

Close to 40 firefighters and 12 fixed wing aircraft responded to the grass fires, with two bulldozers deployed to create a trail for fire trucks to access the area.

Mr Stark also warned Canberra residents against complacency with the threat of bushfires which could occur at any time.

"Historically, when we have El Nino conditions in Australia we tend to get very dry conditions with above average conditions in south east Australia," he said. "That's when you get those really harsh and dry conditions that lead to bushfires."

Australia has posted its hottest end to any year as the impact of one of the biggest El Ninos on record began to be felt across the continent.

Mean temperatures were 0.36 degrees above the previous record for the October to December period, capping what was Australia's fifth-hottest year since the Bureau of Meteorology began keeping national figures in 1910.

Spring was the standout season, with the past three September-November periods comprising the hottest trio on record. Such conditions have led to a busy fire season across southern Australia with a couple of months of summer still to run.

Among the major capitals, Sydney had its third-warmest year on record, just behind the record heat in 2013 and 2014. Statewide, temperatures were 1 degree above average, making it the seventh-hottest year since records began.

- with Peter Hannam