Help us save shining nematolepis
As a result of the devastating bush fires in South East Australia during February 2009, shining nematolepis (Nematolepis wilsonii) became extinct in the wild with the only known site for the species completely and severely burned. You can help Kew safeguard this plant for our future by adopting a seed for yourself, or as a gift for £25.
Fighting for survival
Before we collected its seed, shining nematolepis (Nematolepis wilsonii) was confined to a single population of a few hectares in the upper catchment of the Yarra river, about 80 km east of Melbourne, Australia. Prior to the Black Saturday fires on 7 February 2009, it was also the subject of a translocation program that sought to establish several new populations of shining nematolepis in secure sites nearby.
Due to the same drought that caused this to be such a severe fire season, shining nematolepis seedlings were not planted in the areas chosen to be their new home during the spring of 2009, as originally intended. 173 people lost their lives on Black Saturday and over 2,000 homes were destroyed. Nearly half a million hectares were burnt, destroying the habitat of countless plants and animals such as Victoria’s faunal emblem and the endangered leadbeaters possum. We are yet to assess the full impact on threatened plants in the area, as many roads and tracks are still closed.
Following some welcome autumn rains, over 150 rooted cuttings and seedlings of shining nematolepis were planted in four new areas to establish 'founder' populations. These areas have been fenced to exclude curious wildlife. Follow-up monitoring will continue to help us detect differences in survivorship between cutting-grown plants and seedlings.
Threats to shining nematolepis
The native habitat of shining nematolepis (Nematolepis wilsonii) is in a narrow ecotone between a tall eucalyptus forest, dominated by the world's tallest flowering plant mountain ash (Eucalyptus regnans) and a cool-temperate rainforest, dominated by southern myrtle beech (Nothofagus cunninghamii). The area from where it was known forms part of the protected water catchment that supplies Melbourne, the second largest city in Australia, with a population of around 3.8 million people. Melbourne’s water supply has been steadily dwindling through increasing population and decreasing rainfall and currently capacity hovers at only about 30% and is steadily heading south.
Climate change projections suggest that the water supply to Melbourne threatens the viability of this city and the government is seeking alternative supplies from other catchment areas and from desalination of seawater. Both alternatives involve massive pipeline construction and both have been the target of strong public opposition. One consequence of the fires that have burnt about 30% of Melbourne’s catchment area, is that the post-fire regenerating forests will consume up to 50% more water than the mature mountain ash forests they will replace. Many of the original forests included trees that were around 300 years old and these are the sort of timescales that are required for run-off rates to return to their pre-Black Saturday levels.
Alongside the challenges posed by Melbournes water supply needs and the ever-present possibility of summer bushfires, another threat to shining nematolepis are sambar deer, native to southern Asia (including India and Sri Lanka). Sambar deer were introduced to south-eastern Australia in the 1860s by the Victorian Acclimatisation Society, who sought to ‘improve’ the impoverished Victorian bush by adding plant species regarded as valuable for food, recreational hunting or other resources such as timber.
The past few decades has seen an explosion of sambar deer numbers in the area, alongside an expansion into new sites. While shining nematolepis isn’t a favoured food plant for sambar deer, their stems offer just the right texture and resistance for the stags to ‘de-velvet’ their new antlers each spring. As a result, sambar deer are removing the bark from sapling and mature instances of shining nematolepis. Unfortunately, this plant species is preferentially sought out by sambar deer for this activity and up to 10% of plants had already been killed or damaged by samba deer, prior to the fire in 2009.
After the fires
Previously collected shining nematolepis (Nematolepis wilsonii) seed, has been lodged at the Victorian Conservation Seedbank in Melbourne and duplicated to Kew's Millennium Seed Bank, located at Wakehurst, West Sussex. Some 18,000 seeds are available to help restore this plant species and this precious resource will help the process of growing new instances of the plant from cuttings in nurseries, where more seed can be produced to ensure its survival.
Like many of our capsular-fruited Rutaceae, we have so far had limited, but promising success in germinating shining nematolepis, so the principal material for translocation was grown from cuttings from 31 parent plants. Once Meg Hirst, the seed technician at the Victorian Conservation Seedbank, had developed a successful method for germinating shining nematolepis, seedlings were included amongst the plants used in the translocation.
In the wild, seedlings are usually seen only on ground disturbed by mammals such as the native wombat (Vombatus ursinus) and the introduced sambar deer (Cervis unicolor). If the seeds behave in nature as they do in the lab, we might expect any residual seed in the soil at the burnt site to germinate after overwintering.
Unfortunately, there was no seedling growth six weeks post-fire. In many sites, the humus-rich soil had burnt to depths of nearly 1 m, so any seed in those areas is unlikely to have survived. Any natural germination from soil-stored seed may occur in areas less severely burnt, such as the fringes of the original stand of shining nematolepis. Should germination not occur at the original site by spring 2012, more plants being grown at the Royal Botanic Gardens Melbourne nursery, using seedbanked seed, will be repatriated to the site.
Story and photos by Neville Walsh, Royal Botanic Gardens, Melbourne
You can adopt this seed for yourself, or as a gift for £25.
When you Adopt a Seed, you'll receive a personalised certificate, featuring your plant species, as a downloadable PDF document you can print off, and regular updates over the year from the Millennium Seed Bank.
For an additional £2, you can have an Adoption Pack posted (either to you, or direct to a gift recipient) featuring a certificate and a full colour picture of your species (UK only).
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