Last year, Southern's two AOS squads responded to 89 callouts, a 20% increase on the year before, which was already higher than average.
The Invercargill squad almost averaged a callout every week with 51, and Dunedin's squad was called on 38 times in 12 months.
It comes against a backdrop of increasing drug use and activity in the criminal fraternity.
Last year, the number of offenders in court in Otago and Southland for illicit drug offences rose by 16% compared to the previous year.
The number facing prohibited weapons charges in the regions increased by 20%.
AOS commander Inspector Kelvin Lloyd said increases in instances of weapons falling into the wrong hands and rising methamphetamine use in the Southern district had created a more volatile criminal environment for police.
Earlier this month, the Otago Daily Times reported a mobile meth lab was discovered earlier this year in Invercargill.
"Methamphetamine is a risk factor that we didn't have in previous years,'' Insp Lloyd said.
That risk factor meant police were being encouraged to use AOS squads more often when executing search warrants or carrying out other operations.
"Off the top of my head, it would be one of the higher periods for demand for our services,'' he said.
"There is a tactical option there, in the form of the AOS, if it's needed.
"Everyone is well aware that there are a lot of firearms in the community that have been obtained illegally and that elevates the risk for our squads.
"Everything we are hearing suggests methamphetamine use is on the increase.
"Methamphetamine use is a big concern to us, both in terms of how it affects people in terms of criminality and the health effects that come with it. People on meth are unpredictable.''
He believed the squads - which were part-time and drawn from other areas of police - were resourced to cope with the increase in demand.
Southern police had a large area to cover, he said.
"They have got a substantial rural component and in rural areas there is a higher number of firearms.''
Firearms had been targeted during burglaries. Twenty-three pistols, thousands of rounds of ammunition, four military-style semi-automatic rifles and a shotgun were stolen from a Dunedin address last year.
Members of Hells Angels and the Bandidos motorcycle gang were contacted in regards to buying those stolen weapons.
While police did not keep collated statistics on firearm thefts, Insp Lloyd said anecdotally there appeared to be an increase.
A recent report by Parliament's Law and Order Select Committee said the primary source for firearms for criminals was burglary of licensed firearms owners.
"Rural properties are often targeted as a source of illicit firearms because of the high availability of firearms and their remote location,'' the report said.
Firearm ownership rates in the Southern district - New Zealand's largest and most sparsely populated policing district - are some of the highest in the country. Information released under the Official Information Act shows about 10% of residents in the district hold a firearms licence.
Insp Lloyd said law-abiding firearms owners were not the problem.
"We reinforce the safety and security measures and in general, I think, they are pretty good.''
The select committee has made 20 recommendations to the Government to reform gun laws and crack down on illegal firearms. The recommendations are being assessed by two independent advisers and police.
