Passport to Recovery:

Using citizen science to monitor post-bushfire movement of Koalas on Kangaroo Island

01 / 08

Koalas (Phascolarctos cinereus) were introduced to Kangaroo Island in the 1920s. Eighteen animals from Victoria were released in Flinders Chase National Park as part of a national attempt to protect the species after it was in danger of becoming extinct due to extensive hunting .

Numbers expanded rapidly on Kangaroo Island and by the 1940s there was significant over-browsing impacts on native vegetation (DEW 2020).

In 1997, the South Australian Government initiated the Kangaroo Island Koala Management Program to reduce the island’s introduced koala population to a sustainable level to prevent over-browsing of native vegetation.

The program has involved relocating koalas, managing koala habitat, monitoring koala density and tree condition, and sterilising koalas. A population survey has been conducted every five years to estimate the size of Kangaroo Island’s koala population. In addition, tree condition is monitored annually.

Since the program began 23 years ago, more than 12,500 koalas have been sterilised, making it one of the largest fertility control programs in the world. About 3,800 of these koalas have been relocated to the state’s South East.

The reduction in koala densities through this active management has resulted in improvements to the health of Kangaroo Island’s unique vegetation communities and ensured the sustainability of the koala population itself (DEW 2020).

The summer of 2019-20 saw unprecedented bushfire events across Australia. Kangaroo Island was seriously impacted, with almost half of the island burnt (DEW 2020).

Prior to the bushfires, the Department for Environment and Water (DEW) estimated the Kangaroo Island koala population at 48,000.

Following the bushfires, DEW estimates that approximately 8,500 koalas remain, based on the assumption that most koalas within the area impacted by the bushfires perished (DEW 2020).

In 2019-2020 bushfires also devastated much of Eastern-Australia and have lead to koala's along the east of Australia being listed as endangered.

In South Australia koala's are still abundant and my serve as a insurance population to assist in the recovery of the endangered populations in the east.

Passport to Recovery is a citizen science program aimed at getting visitors and locals involved in the post bushfire monitoring of Kangaroo Island.

The Passport to Recovery Koala Compass project, collects data on the number of Koalas on the island and monitors their movement back into bushfire affected areas.

Below is a map of koala sightings from citizen scientists in the Passport to Recovery program

Click on a koala icon to see information associated with that sighting and any photos taken by the citizen scientists who submitted the recording.

It turns out that some citizens are a little confused by the definition of koala. See if you can find the vocalising dog and the crochet cake records!

Koala Compass map

An explanation of bushfire severity/intensity calculations

Higher Bushfire intensity values are correlated with more green vegetation destruction in that area during the fire.

The delta Normalised Burn Ratio (dNBR) is calculated by subtracting the NBR of the Island's vegetation extracted from Landsat 8OLI satellite imagery taken on the 20th February 2020 from the NBR of the Island prior to the fires in November of 2019, using the formula (NIR -SWIR)/(NIR +SWIR). Near Infrared (NIR) electromagnetic spectrum (0.65 - 0.94 micrometres/microns) values recorded by the satellite sensor 705km above the earth's surface are higher in healthy green vegetation due to their leaf structure and its ability to reflect high levels of atmospheric NIR radiation. After fire, leaves are often destroyed or become brown from heat effects, reducing the NIR reflectance back to the satellite, leading to much lower values of NIR after the fire, until the vegetation regenerates. Depending on what type of vegetation has been burned, these values may remain low for years if tree canopy has been destroyed, or recover quickly in teh case of grass and the more fire-resilient species such as Grass Trees (Xanthorrhea semiplana). ShortWave InfraRed (SWIR) radiation (1.55 - 1.75 microns) is sensitive to moisture content in vegetation and the underlying soil, thus will have higher values recorded by the satellite sensor after fire has scorched the ground.

Some of the koala sightings from our wonderful citizen scientists!

These sightings from citizen scientists indicate that koalas are yet to fully move back into areas that were most severely impacted from the 2019/2020 bushfires, particularly in the Flinders Chase National Park area.

Keep checking back in on the map for more updates on KI koala movements from our dedicated citizen scientists!