The information, obtained by the Herald through an Official Information Act request, has revealed that as of October there were 827 people in the Wellington Police District on the National Gang List (NGL) - which records prospective and patched members.
This has risen from 449 in October 2016.
As well as this, offences in which a gang member has been identified as the offender has increased sharply from 495 in 2016 to 812 in 2020.
In a statement, Wellington District commander superintendent Corrie Parnell said gang membership is generally increasing around New Zealand, and this was not an issue specific to Wellington.
"The reasons for this are many and varied, and include socio-economic factors, health and educational issues, pressure from others, and drugs.
"What we are seeing is that gang membership country-wide continues to increase, but by the same token seizures and forfeitures of assets are also continuing to increase."
University of Canterbury's Criminal Justice director Dr Jarrod Gilbert told the Herald we can't rely on this data to be 100 per cent accurate.
"These data are the same as the general gang data and that suffers from some very specific methodological problems and that is that it's easy to get on the list and very difficult to get off."
He said what this does shows is a general indication of growth - but exactly the numbers we just don't know.
"The gangs for some part have just come back into vogue all of a sudden - they're coming off a very low base."
Relatively quickly Gilbert said we have seen this turnaround, something which he said was as simple and as complicated as changes in fashion.
"The gang scene is much more complex than we've always given it credit for, but more so now than any other time in our history. We've got groups on one hand that are hard-core drug dealing organised crime groups, then on the other hand we have other groups that are genuinely trying to make the lives of their members better."
The Wellington Police District covers the southern part of the North Island with its northern border stretching from Peka Peka in Kapiti, across the Hutt Valley and over the Tararua Ranges to the Wairarapa.
It also includes the Chatham Islands.
Echoing a similar sentiment to Gilbert, Parnell said Because gang membership is fluid by nature it can be difficult to quantify and information held is only as good as the day it was collected.
"In saying that, increases in Wellington District are due to more robust recording methods to validate gang membership, resulting in the formal identification of previously unconfirmed gang members."
Multiple gangs are established in the Wellington region, these include the King Cobras, Rebels MC, Black Power, Head Hunters MC and the Mongrel Mob.
Late last year the Herald revealed the Aotearoa gang scene had exploded with new faces and rapid growth.
Data obtained by the Herald found for the first time, there were more than 7000 gang members - an increase of 50 per cent in just three years.
However, Gilbert said gangs were not all alike and there were chapters up and down the country attempting to break the mould and the groups that are moving in that more social direction aren't going to require the same response.
"When we're talking about organised crime we need to talk about organised crime, not talk about gangs, because there are a number of gang members that aren't involved in organised crime, and there are huge numbers of people that are involved in organised crime that aren't in gangs."
Gilbert said the gangs are one thing and organised crime is another - and we need to distinguish between the two because while they sometimes intersect, they're not synonymous.
In October six people were arrested following a four-month long investigation into gang-related offending which culminated in seven search warrants across Wellington and Upper Hutt.
Those involved were charged with a number of offences, including receiving stolen property and unlawful possession of an imitation firearm.
About 60 police staff were involved in the operation.
Parnell said gang offending is not an issue that police can solve alone and it requires a multi-faceted approach because of the many factors at play.
