Pest control experts say they are finally starting to make a dent in New Zealand's exploding wallaby population, as a battle to stop them destroying native forests rages on.

The government last year allocated $27 million towards culling wallabies as part of its Job for Nature programme.

Among those to receive funding is Dr Tim Day, a pest control expert working in the Bay of Plenty.

Wallaby numbers have been growing in the area in recent times, and Day describes them as a "little known villain".

"A lot of people wouldn't have seen a wallaby in the wild, and they're used to actually seeing them in the Australasian exhibit at the zoo, so they're kind of perceived as being a bit cute and furry when actually they're just as nasty a pest as any of the others we have."

Day has been working on a farm in the backblocks of Rotorua, tracking and poisoning wallabies that are slowly spreading further afield.

His efforts have seen almost all the wallabies eliminated from the immediate area, as well as hundreds of possums, which are often killed as a byproduct of the wallaby eradication.

It's good news here, but across the country, wallabies are wreaking havoc.

While Day says it's often estimated there are 70 million possums in New Zealand, it's much harder to measure for wallabies.

"It's definitely tens of thousands of wallabies, I wouldn't know if it's hundreds of thousands or millions.

"It's very hard to put a number on, we just simply haven't historically had the resources, funding, to do the basic research."

Wallabies were first introduced in New Zealand in the 1870s, and they have gone from strength to strength.

It's estimated up to 1.5 million hectares in the South Island and up to half a million in the North Island are infested.

While possums and rats are often the poster pests for our predator-free 2050 goals, Day says wallabies are just as dangerous.

"The problem is they very quietly go about eliminating seedlings. It's just kind of this creeping disease in a way, over time they can completely stop regeneration of a forest."

But what has long felt like a losing battle is slowly starting to seem hopeful. The recent government funding means poisoning, shooting, tracking and culling can now take place at a much larger scale.

There are now 22 people employed by the national wallaby management programme: 16 in the Waikato/Bay of Plenty and six in Canterbury.

Bay of Plenty Regional Council wallaby programme leader Ron Kayzer says he has high hopes for 2021 after controls had been moving relatively slowly for the past 15 years.

"Each regional council's been putting in a limited amount of money, because they've only had a limited amount of funds, and this is quite a big boost that means we can actually start to get some real runs on the board.

"I would suggest there will be quite a few busy contractors out there and there's hopefully going to be a whole lot of dead wallabies on the ground."

Among those contractors are conservation dog handlers Gus Knoopers and Kim Tiri.

Tiri's job was created as a direct result of the Jobs for Nature programme, which the government estimated would create 11,000 jobs over four years.

So far it's fallen well short of that - just 801 people have full-time jobs.

Projects have been approved which are estimated to create 2229 jobs in their first year and 5410 jobs over the project lifetimes.

Knoopers is hopeful they'll get more two more dog handlers as they scale up their work.

"Any young person that's keen and wants to learn anything about wallabies, this is the time to do it."

Day says he expects wallaby conservation efforts will quadruple over the coming years - but he warns elimination is a long way off, with control likely to continue right through to New Zealand's predator-free 2050 target.

"Wallabies live in a lot of places where people do a lot of recreation, walk their dogs and all that sort of thing, so we're going to have a lot of challenges about how to build control techniques that also suit what we as a society want to have going on - the reality is if we don't do the control, there'll be nowhere to do the recreation because those forests will collapse.

"We have to do something about it, but we're going to have to get smarter about how we do that over time."

-RNZ/Nita Blake-Persen.