This time last year north coast communities were already experiencing the devastating impacts of severe bushfires. Little did we know that by early November 2019 Nightcap National Park would also come under siege. On 7th November the Mount Nardi fire in Nightcap National Park commenced and burned for 71 days before being declared out on the 18th January.
One of the more significant impacts of the bushfire was the loss of some of the population of the critically endangered Nightcap Oak (Eidothea hardeniana). The Nightcap Oak is a medium to large sized tree in the Proteaceae family and is representative of genetic lineages which date back 110 million years; providing a living connection to the flora of the Gondwana supercontinent.
The only population of Nightcap Oak occurs in a small area of core rainforest in Nightcap National Park, with the population extending into Brush Box rainforest and the edges of the wet sclerophyll forests with rainforest and eucalypt emergent. This limited distribution places the species at particular risk from bushfires. The low number of individuals and the even lower number of adults contributing to reproduction, exposes this critically endangered species to a high risk of extinction.
Research indicates that there are fewer than 390 individual Nightcap Oaks, of which approximately 125 are mature adults. From these adults, only ca.25 contribute to geneflow and survival of the species’ limited population.
Dr Robert Kooyman, with the NSW National Parks and Wildlife Service (NPWS), continues to assess the Nightcap Oak, gathering data on the species response following the 2019-2020 bushfires.
The NPWS reported last month that 71 individual Nightcap Oaks were burnt to varying levels during the recent event. Of these, 17 individuals are showing signs of recovery. These initial results were discussed in the recent Saving our Rainforests from Fire panel discussions.
Although there have been some positive indicators, Dr Robert Kooyman, a leading ecologist and member of Big Scrub Landcare’s team of scientific advisors, says, “It is still unknown how many individuals impacted by the fire were part of the species breeding population. What we do know is that loss of any individuals will impact on the species survival and its evolutionary potential.”
Almost one year on from the bushfire, the results of scientific assessments indicate some resprouting of rainforest trees, including a few individuals of Nightcap Oak. Overall the recovery of the rainforest is very slow, and in some cases the forests continue to decline. The loss of canopy trees will take centuries to replace, but the good news is that much of the core area of Gondwanan rainforest survived, hidden away in deep time moist forest refugia areas. Despite the impacts of fire and climate change there is hope for their survival into the future.
Contributed by Dr Robert Kooyman