Eucalyptus gunnii spp. gunnii or as its commonly known Miena Cider Gum is an endangered species of Australian tree endemic to the Tasmanian highlands coldest and most spectacular areas. For 25 days I took part in and documented the most comprehensive distribution study of the tree ever. The study was undertaken because of the rapid decline of the species over the last 30 years.
Gunnii is thought to be a climate change indicator species as it is the most frost tolerant Eucalypt species only growing on the boundaries of frost hollows in Tasmanias highlands. Even in the middle of summer night time temperatures can regularly drop below -5 degrees celsius and winter maximums rarely above 15. Gunnii manages to survive in these frost hollows because of its unique adaption of having a very sugar rich sap. Sugar is a natural anit-freeze so while the other eucalyptus in the area are at best dormant Gunnii thrives, or at least that's the evolutionary idea.
However, more than 60% of the know population of this tree has expired in the last 30 years with the primary cause being global climate change. Long droughts followed by warmer winters are the primary cause of its rapid die back as well as the impacts on soil from sheep and cattle grazing in the area. With much of Gunnii's theoretical distribution laying inside private land owned by Gunns, Tasmanias biggest logging company, its true numbers were highly speculative and until this survey largely unknown.
The vast majority of the known population is in close proximity to the town of Miena 140km from Hobart hence its common name Miena Cider Gum. The other half of the name "Cider Gum" refers to historical accounts of its unusually sweet sap being fermented and drunk as an alcoholic beverage by local aboriginal groups. Exacting scientific accounts of its traditional alcoholic use are nonexistent but there is abundant hard evidence that they did at least harvest the sweet sap. I had the opportunity to taste the sap straight from the trunk of a tree we discovered during the survey and it is as sweet as honey but with a slight eucalyptus flavour.
While the population close to Miena has has been carefully studied the properties further into the wilderness owned by Gunns have never been surveyed due to Gunns obvious economic interest in not knowing. However the recent acquisition of many of Gunns properties by the Tasmanian Land Conservancy (TLC) allowed ecological scientists access for the first time. These photos are from that first round of surveys covering 63 sites on 7 different properties and covering a very large area of the Tasmanian highlands.