Flora in the Torndirrup Area

 

‘Some 500 species of plants grow in the Torndirrup National Park which is less than 4,000 hectares.  For such a small coastal area the range of vegetation types shows unusual diversity …   From a distance the vegetation appears to be composed of low heath or stunted woodland, yet there are groves of very old trees with enormous girths to their weathered trunks …‘The diversity of plants is largely due to the variety of areas where different vegetation types can grow. The plant communities often indicate the underlying soil structure and type. Thus Peppermint, Woolly Bush and Acacia Littorea are mainly associated with the alkaline sands derived from weathered limestone. Open woodlands of Holly-leaved and Slender or Coastal Banksia, containing patches of melaleuca shrublands and interspersed with eucalyptus thickets, are generally over deep sand.  Areas of low Oak-leaved Banksia heath occur in less well-drained localities.  Swampy bogs contain distinct plants like the Swamp Banksia and the Albany Bottlebrush and the insectivorous perennial, the Albany Pitcher Plant. ‘    Vic Smith, (1991: 19).

  
Isopogon Formosus

Isopogon Formosus Torndirrup Heath

During the wildflower season (September to January) the usually undifferentiated heath around Torndirrup and Frenchman Bay becomes first a mass of white and yellow flowers followed by swathes of blues, purples, oranges, reds, pinks and purples – the magnificence and timing of each season dependent on the climactic  conditions of each year.

Karri Forest Goode Beach

Karri Forest Goode Beach

A delightful ‘miniature’ pocket of ‘Karri Tall Open Forest’ exists high above Goode Beach ‘which appears to have close floristic affinities with the Karri forests in the Denmark Walpole – Manjimup area…’

(Sandiford & Barrett 2010:74)

CHALLENGES AND THREATS:

With 143 species identified as under threat of extinction in WA, about $1.6 million currently was allocated in 2012 to WA’s Natural Resource Management programme for critically endangered flora recovery. It is considered that unless timely conservation action is taken, many of these plants are estimated to have a 50 per cent probability of extinction within the next 10 years. Measures to establish new populations and to control invasive weeds, feral animals and disease are some of the strategies currently utilised to conserve these precious species into the future.

 

Dieback, photograph by Sally (Lillepod)
* Little Blue Wren in plants affected with Dieback photograph by Sally (Lillepod)

 The impact of Phytophthora cinnamomi (dieback), aerial canker, loss of habitat, commercial exploitation, inadvertent recreational damage, changing fire regimes as well as the potential ravages of hydrological change and climate change/variation, challenges and severely impacts ecosystems and the survival and interactions of species within them. In a recent survey of Albany’s vegetation status it was stated with regard to the significance of climate change:

‘Predicted climate change is a future threat to the vegetation …[and] terrestrial habitat as a result of climate change due to the anthropogenic emission of green house gases has been identified as a key threatening process in the Australian environment (EPBCn Act 1999, Environment Australia 2001b). In the south-west of Western Australia there has been a significant decrease in autumn and winter rainfall since the mid 20th century and mean annual temperatures have increased during the 20th century (Hennessy et al. 1999; IOCI 2005). … These changes are likely to result in reductions in water tables, increased evaporation and a prolonged dry season, with impacts on vegetation predicted to include changes in relative abundance, range contractions, changes in community composition, changes in flowering times and increased vulnerability to stress induced factors such as Phytophthora dieback (Hughes 2003)’.

  E.M. Sandiford & S. Barrett, (2010: 34)

Banksia brownii plants ready to be planted back into the wild. Photo: Sarah Barrett, DEC
**Banksia brownii plants ready to be planted back into the wild. Photo: Sarah Barrett, DEC

 In the Torndirrup area for example, the population reduction of Banksia brownii (or Feather-leafed Banksia) has been a matter of real concern due to threats from the mould Phytophthora cinnamomi and from frequent fire.  Spraying plants with a fungicide, implementing an appropriate fire management plan, collecting & conserving seeds to recreate populations are all part of an integrated conservation strategy employed by the Department of Environment and Conservation (DEC) to conserve the species.   In 2010 DEC undertook plantings in the Torndirrup National Park to re-build dwindling populations.  This project and others like it, involved researchers from the WA Threatened Flora Seed Centre [i]. To date these activities appear to have been successful – as have similar translocation plantings recently undertaken in the Stirling Ranges which have shown an encouraging 86% survival rate.[ii]

Another important example of an endangered plant, is the beautiful Blue Tinsel Lily (Calectasia cyanea) – which was thought until relatively recently, to be limited to a single population of plants within the Torndirrup National Park  With approximately only 180 mature plants identified in 2003, Calectasia cyanea was declared as Rare Flora under the Western Australian Wildlife Conservation Act, and ranked at that time as ‘Critically Endangered’.  Although some additional mature plants have since been found, the species no longer meets all aspects of this criteria – but because a single population can easily be damaged or destroyed by a single event such as an inappropriate fire regime – it currently retains this status. [iii].

Among other endangered species is the Isopogon uncinatus or Albany Cone Flower, first described by Robert Brown in 1830 from collections made from King George Sound area by William Baxter in 1828.  Although  some small populations of this relatively rare plant survived fire in the summer of 1997, it still remains threatened from diseases such as ‘dieback’ and canker, as well as fire regimes, recreational activities and potential climactic events. [iv]


MAJOR REFERENCES

(2010) E.M. Sandiford and S. Barrett, Albany Regional Vegetation Survey: Extent, Type and Status, South Coast Natural Resource Management Inc. and City of Albany for the Department of Environment and Conservation.

(1991) Vic Smith with Michael Bamford (illus.)., Portrait of a Peninsula: The Wildlife of Torndirrup, Wallace Smith.

PHOTOGRAPHS

*Photograph of Little Blue Wren in shrubs affected with Dieback, taken by Sally (lillepod), Flickr Commons available at:http://www.flickr.com/photos/64250623@N08/6663914435/in/photolist-b9SiAt-e1Y3fM-d63VCf-hFzXUn-d6d9CU-9x7ogV-e4eh6e-81e4GM-7JVUzp-8Sp2Se-dvwC2N-dvqW58-duSEw5-8R1fk2-9T7NHi-ifNSwA-ifNSt9-ifNSvJ-duLVGc-duM1QD-9TaBK1-9T7NJc-dkW2Mb-9VcsPM-csmoLS-csmoZw-ejAxoT-9Gw3U3-88GvS5-8xoTxc, under license: Attribution-NonCommercial-No Derivs 2.0 Generic

**Photograph of Banksia brownii plantings by Sarah Barrett DEC, Flickr Commons, available  at: http://www.flickr.com/photos/71670801@N06/7933434314/in/photolist-d63VCf, under license: Attribution-NonCommercial-No Derivs 2.0 Generic

NOTES

[i]It’s an ongoing cycle of collecting the seeds from the bush; storing them in the seed bank; germinating a portion of in seeds in the lab; and then re-introducing the seedlings into a safe environment with ongoing monitoring systems in place to ensure their survival.’ Information also derived from the caption associated with the photo by Sarah Barrett (DEC) attributed above. See: http://www.abc.net.au/local/audio/2010/09/06/3004291.htm

[ii] DEC, [media statement], May 9, 2012 ‘Rescue Effort for Critically Endangered Flora’

[iii] Department of Environment and Conservation. (2009). Blue Tinsel Lily (Calectasia cyanea) Recovery Plan, DEC, Western Australia; and http://www.environment.gov.au/biodiversity/threatened/publications/recovery/calectasia-cyanea.html