Police data shows 43 armed offenders squad (AOS) callouts in Southland in the year to August compared with 20 in Otago.
Southern squads have also been deployed more often this year than those in Wellington or Auckland.
Police cannot say why that is the case.
Southern District prevention manager Inspector Joel Lamb said it was also difficult to pinpoint why there were more callouts in Southland than Otago so far.
He noted squads in the South were almost always deployed as a public safety precaution and saw action extremely rarely.
"I can't remember the last time they fired a shot."
In Otago, squads had been deployed in Dunedin 13 times so far this year, compared with seven times in the rest of the province.
Callouts peaked in 2016 with 83 in the Southern District, including 48 in Southland, 31 in Dunedin and four in rural Otago.
The number of callouts dipped in 2017 but has picked up again this year, which is set to be another big year for the AOS in the South.
So far this year the southern squad has been deployed 63 times, more than in Auckland City (19), Counties-Manukau (39) and Wellington (59).
The number of squad deployments this year in Canterbury has dwarfed any other police district in New Zealand at 122, followed by Bay of Plenty and Waikato (66 each) and Southern (63).
There are 17 squads nationally, made up of nearly 300 part-time members.
Armed offenders squads are deployed to deal with armed offenders and typically operate by cordoning, containing and appealing to the armed individuals.
Police national response and operations manager Superintendent Chris Scahill, of Wellington, declined to specify the number of squad members in the Southern District, or the number of squads, saying the information would be likely to "prejudice the maintenance of law".
However, the squad in the Southern District was considered to be adequately staffed, he said.
There was one female squad member in the South and 10 others nationally.
