Despite esteemed leaders posing with koalas at the G20 for publicity, as a nation we still take for granted one of Australia’s great animal icons (one which is widely recognised overseas).
Koala numbers are quickly declining due to loss of habitat and an increase in encroaching human activities.
Let’s stop taking koalas for granted and realise we need to protect those remaining from harm. We need to halt their decline and work hard to grow their numbers.
The koala (Phascolarctos cinereus) is an Australian marsupial. It’s the only surviving animal from the Phascolarctidae family.
Its closest relative is the wombat. Bet you didn’t expect this.
Both the koala and the wombat have pouches that face backwards. This is okay for the ground-dwelling wombat, but koalas need pretty strong pouch muscles to ensure the safety of their young ones, which are called “cubs”.
Breeding for the koala
In Queensland, koalas breed from August to January. Young are generally born in summer, but some can also be born in autumn.
Adult males use an interesting bellowing / grunting noise to attract their mates (and tell other males to get lost).
Safety and protection during this breeding season is vital. Any high-level human activity during this time can greatly affect koala breeding cycles.
Koalas come in a range sizes. Adult males can be between 4kg to 14kg and females can be between 4kg to 10kg.
Why the amazing size variation? Northern koalas – those from northern NSW through to northern Queensland are much smaller than their southern counterparts.
Where koalas live
Koalas generally live most of their lives in trees (they’re arboreal animals) and use the ground to move from tree to tree (which is when they’re most vulnerable).
Koalas are mainly found along the eastern seaboard of Australia from Queensland to Victoria and including South Australia.
They live in eucalypt sclerophyll forests and woodland areas. Their range depends on the size of their habitat and the quality and suitability of the food contained within that habitat.
Their habitat can range from 2 hectares to several hundred hectares. Not surprisingly, koala numbers differ depending on the size of the forest supporting them.
Koalas generally live in open woodlands comprising eucalypts.
Their diet is based mostly on the leaves from a number of Australian eucalypts. Their limited and very focused diet means koalas don’t get a lot of nutritional or caloric content from their food, a reason for their extremely snoozy habits – they sleep for up to 20 hours per day (so don’t expect a lot of conversation).
Here are the names of some of the trees from which koalas eat leaves:
1. Blue Gum (Forest Red Gum) Eucalyptus tereticornis
2. Tallowwood microcorys
3. Grey Gum propinqua, E. punctata and E. major
4. River Red Gum camuldulensis
5. Swamp mahogany robusta
6. Flooded gum grandis.
Threats to the koala’s existence
Koalas appear on the Australian Government’s EPBC Act* as vulnerable and Queensland’s NCA** as regionally vulnerable.
Koala numbers have dropped by some 43 per cent in Queensland, with South East Queensland koala numbers falling from 25,000 to between 4,000 and 2,000 in 10 years.
This is due to the massive reduction of their already limited habitat along the east coast of Australia .
Around 80 per cent of the eucalypt forests koalas rely on for their food have been affected.
The remaining 20 per cent of forest left is not protected and a large portion of it is in private hands, meaning anything can happen to much of the remaining habitat. This further threatens the existence of the koala.
Reasons for the decline in koala numbers:
1. loss of habitat
2. increased disturbance by humans
3. injury or death from traffic
4. injury or death from dogs and cats
5. effects of garden pesticides getting into waterways
6. increased competition for food and territory because of overcrowding
7. increased stress on animals, making them more susceptible to disease
8. bushfire, which can completely wipe out fragmented forest pockets
9. forest dieback from land degradation, soil nutrient leaching, erosion and exposure to weather.
List from the Koala Foundation: Threats to the koala
Koala numbers in the Tamborine Mountain Escarpment Protection Precinct rely heavily on the preservation of the remaining eucalypt forest. Koala numbers are at risk if clearance of key koala habitat occurs.
In November of 2014, the National Parks Association of NSW held the national Great Koala Count to document koala sightings throughout Australia.
Some 308 citizen scientists participated in the count, recording more than 1,000 koala sightings. This was a 54 per cent increase from the 2013 number of koala sightings recorded.
The Scenic Rim citizen scientists (some of whom were on Tamborine Mountain) took on the challenge of counting koalas in the region. There were 12 citizen scientists in the Scenic Rim – more than any other local government region in Queensland barring the Gold Coast (who had 66 citizen scientists).
The koala count for the Scenic Rim reached 26 (low compared with the Gold Coast and Sunshine Coast, which reached 218 and 61 koalas respectively) and on par with Moreton Bay and Logan.
Author of the 2014 Koala Count Report: Dr Grainne Cleary, Wildlife Ecologist.
Great resources on the koala
Qld Department of Environment and Heritage Protection: Koala maps
The Koala: All about koalas
Australian Koala Foundation: Save the koala
Australia Zoo: Mammals: Koalas
NSW Environment & Heritage: Koala
Australian Koala Foundation: Enlisting in the koala army
*EPBC Act: Environment Protection and Biodiversity Conservation Act 1999
**Queensland’s NCA: Nature Conservation Act 1992