GPS tracking technology is being used to monitor the movements of koalas in forests on the New South Wales mid-north coast in a bid to stop a severe decline in their numbers.

Koalas are being fitted with lightweight GPS tracking collars to determine how much state forest logging is affecting their movements, and to assess whether there are enough protection zones in place, and how much the animals use regeneration areas after harvesting.

The research is being done by the NSW Department of Primary Industries (DPI), the Port Macquarie Koala Hospital and the Forestry Corporation.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 44 seconds 44 s The Department of Primary Industries captured this video of a koala being released after being fitted with a GPS tracking collar

DPI principal research scientist Dr Brad Law said it formed part of the overall NSW Koala Strategy and the findings would be considered by the Natural Resources Commission.

"One of the key things we want to look at, is how much do they really need those areas that are retained and protected from logging, and how much do they use the young trees that come after an area has been harvested," he said.

"It's very hard to know how much of an area should be protected, " Dr Law said.

"Is there currently enough protection in place there for koalas?"

It is hoped the koala tracking project will help halt a decline in koala numbers in NSW and Queensland. ( Supplied: Bimbi Park )

Koala Hospital clinical director Cheyne Flanagan said the research was another step towards saving koalas from extinction in NSW and Queensland.

"It's all about conserving the species, and all about managing them in a better way," she said.

"Every bit of information that happens, no matter what field of research, with koalas out there, is all important to put the little pieces in the puzzle.

"Koala populations in NSW and Queensland are in serious decline, and under great threat of ending up not being sustainable.

"Victoria and South Australia are different, they have far more koalas than we do, but give it time, they will be in the same situation."

Where do koalas go and what trees do they use?

All koalas fitted with tracking collars are also given a complete health check — a clinic can even be run in the bush. ( Supplied: Department of Primary Industries )

As part of the project 10 koalas will be fitted with tracking collars and the monitoring will continue for around 12 months based on the expected battery life of the GPS collars, which transmit information.

So far, two koalas, Traecey and Dazza, have been captured, fitted with the technology, and released.

Dr Law said the first koala, Traecey, was released late last year and they had already received some interesting data tracking her movements through logged and unlogged terrain.

"So far, it's early days, she's got a little home range in between two gullies in the forest, but we are also able to get information on what sort of trees she uses," he said.

"She's using a whole range of trees, some we don't expect, they aren't typical koala trees for her to use.

"So particularly at the moment with the warm weather we are having, she is using trees with quite dense foliage, in the shade, trying to keep cool during the day.

"In those areas that do get harvested, some trees do get left behind for wildlife, so we can look and see what sorts of trees the koalas are using."

This map shows GPS tracking locations for koala, Traecey, revealing she has used logged and protected areas. ( Supplied: Department of Primary Industries )

Dr Law said they were also very interested to see how much Traecey used logged areas with young, regenerating eucalypts, compared to mature forests.

"She is actually using both parts of the landscape, those that have been logged, and those that have been protected," he said.

Koalas receive health checks in a bush clinic

Cheyne Flanagan, Port Macquarie Koala Hospital clinical director, and vet Irene Rodriegez give a koala a health check before fitting a tracking collar. ( Supplied: Department of Primary Industries )

The project will also provide information about the health of the koala population.

Staff from the Port Macquarie Koala Hospital are helping fit the collars and will conduct full health assessments for all the koalas involved, looking at their age and reproductive status.

The checks can be done indoors or outdoors.

"We have a mobile clinic we set up out in the bush, with a table and an anaesthetic machine and a portable ultrasound machine that was donated, and we can do a full assessment out there in amongst the trees and the birds," Ms Flanagan said.

"We anesthetise the koalas and give them a full health screen and then fit the radio collar on, the collars are really lightweight — they only weigh about 60 grams and are really good."

A volunteer cares for a koala at the Port Macquarie Koala Hospital. ( ABC News: Emma Siossian )

The first two koalas fitted with collars, Traecey and Dazza, were both treated at the Koala Hospital for the bacterial disease, ocular chlamydia, before being released.

The disease can cause blindness and infertility.

Ms Flanagan said the dry, hot summer had affected many koalas and made diseases worse.

"Koalas are in dire straits the same as everyone else. They are really dehydrated and suffering," she said.

"When it's very dry … it increases the incidence of chlamydia, it just seems to bring it on, because they're not coping."