There are more than 6500 patched or prospective gang members across New Zealand - and that number is set to swell due to a resurgence in the scene making the criminal groups "cool" again.
Figures provided to the Herald under the Official Information Act reveal that there are 6535 "patched and prospect" gang members on the National Gang List.
The list is held by the Gang Intelligence Centre, a police-led agency set up in 2016 which draws on knowledge from several government agencies to build detailed information about the activity of gang members and prospects.
The information is used to reduce illegal gang activities and to identify and offer support to the members and associates who want out, both for themselves and for their children.
There are 10 main gangs in New Zealand: Head Hunters, Bandidos, Hells Angels, King Cobras, Black Power, Mongrel Mob, Tribesmen, Rebels, Devils Henchmen and Highway 61.
There are also a number of youth gangs including the Crips and Bloods, location-specific gangs such as South Auckland's Killer Beez and a recent influx of Australian-based gangs like the Rebels and Comancheros.
The national list shows that Bay of Plenty is the district with the most gang members, with 1359 on the list.
But the wider Auckland area - City, Counties Manukau and Waitemata - boasts almost the same, with 1328 patches and prospects counted.
Police refused to give the Herald a breakdown of specific gangs for each region, saying that "making the information available would be likely to prejudice the maintenance of the law, including the prevention, investigation and detection of offences".
They also cited privacy and an impact on the supply of information to police about gangs as reasons they would not be drawn further on the matter.
"Additionally, this information is withheld to prevent the possibility of disclosure leading to the provocation of inter-gang rivalry and an increase in serious offending," said National Intelligence Centre manager Trevor Benson.
New Zealand's leading gang expert, Dr Jarrod Gilbert, said the NGL was "incredibly important" and effectively backed up what he was hearing from the streets about gang numbers.
"For the last few years 5000 [gang members] has been the short line," he said.
"But what we've seen is some growth on that.
"Anecdotally from the street, it's quite clear that the scene is growing."
Gangs in New Zealand had not had such significant growth since the 70s and 80s, Gilbert said.
"The scene shrank significantly in the early 2000s and they failed to reverse that with their membership," he explained.
"Because of that, the scene also aged - but now we are seeing a reversal of that."
The resurgence of gang popularity in recent years could be put down to several factors, he said.
"When new people come into it and the scene seems vibrant and cool, that tends to attract new membership.
"One influence that may have sparked that is the Australian gangs moving in here - starting with the Rebels MC but certainly not ending with them.
"Also existing clubs have woken up from a slumber, they've upped their game because of this new competition.
"That has revitalised the scene."
Social media had also given gangs a never-before-utilised platform to spread their reach and draw in new blood.
The Comancheros and Head Hunters are two gangs who often publish on social media.
Gilbert explained why some areas had higher gang populations than others.
"Gangs breed gangs and they become embedded in parts of the country," he said.
"In a district the gang won't be prevalent everywhere, it will just be some suburbs - but boy oh boy, where it does exist, it exists.
"[Bay of Plenty] has always been a hot bed for the gangs - particularly the Mongrel Mob; it's their fatherland, it's where they started and so they've always had a fairly big base there," he said.
"It's a red area for sure, Mongrel Mob through and through."
The more prevalant gangs in Northland continued to be the Head Hunters, Tribesmen and Black Power.
Auckland was "very very crowded" with "everyone" vying for power.
"There is also a concentration of LA-style street gangs in Auckland like the Killer Beez," Gilbert said.
"Traditionally the South Island has been very different, but even that is changing.
"It used to be dominated by mainly Pākehā clubs - like the Road Knights or the Epitaph Riders - but it's also changed dramatically and now those groups are disappearing or shrinking and others that were traditionally in the North Island are moving in like the Tribesmen, Head Hunters and King Cobras."
The gang landscape across the country was "changing dramatically", he said.
"For decades after the big wars of the 70s and 80s the country went into a form of checkmate where everyone had their areas," Gilbert explained.
"Nobody could move on the board and the gangs tended to stick to their areas, no one was scrapping for turf anymore because it had all been divvied up so there was less violence.
"But those traditional territories have fallen away and now gangs are establishing themselves in other areas.
"New gangs are establishing themselves in some areas and established gangs are moving in where they didn't exist before.
"We're starting to see jostling and an increase in gang violence. It's like when a room gets increasingly crowded - people invariably get elbowed."
Gilbert said while gang numbers were set to rise, the general public should not be overly concerned.
It was easy for authorities to make gangs "like the bogeyman", he said.
"I think that gangs have traditionally been ripe for moral panic and political concern - often that's been not as warranted as someone might think," he said.
"But we need to keep gangs in perspective - whilst they are more criminal than your average Joe, we can tend to blame too much on them.
"There are other crimes within New Zealand that are far more significant, including family violence and white-collar crime.
"It's very, very easy to blow gangs out of proportion, particularly because when violence occurs it's alarming.
"But violence exists between gangs, they don't concern themselves with outsiders so unless you're entering their world, you're ok."
Police refused to comment on what specific information was held on the NGL and how it was gathered.
"The NGL is based on validated information and is continually examined," a spokesperson said.
"[It] holds information in relation to the 34 identified New Zealand adult gangs named in legislation - Prohibition of Gang Insignia in Government Premises Act 2013.
"We cannot share how we compile the numbers or how we validate someone."