The Cat's Claw Creeper has been listed as a weed of national significance causing serious damage to vulnerable riparian zones – so why is this weed such a massive problem? In this episode, you will learn why the Cat’s Claw Creeper can be considered a contemporary land and water management issue and why it is listed as a noxious weed.
WARNING – Aboriginal and Torres Strait Islander viewers are warned that the following video may contain images and voices of deceased persons.
[Screen reads – Environmental Weeds. Any other plant that causes or has the potential to cause negative environmental, social or economic impact]
Narrator – Environmental weeds are subtle invaders in the natural ecosystems and often are not adequately recognised as a significant threat to Australia's biodiversity. Second to habitat loss, alien species such as weeds and pest animals are in the greatest cause of biodiversity decline in Australia.
[Screen reads – Biodiversity decline is the loss of variety in living systems. Australia has experienced the largest documented decline in biodiversity of any continent over the past 200 years.]
Species and ecosystems have complex and important interrelationships. Some species play important roles in the maintenance of ecosystems
[Screen reads – Riparian Zones. The interface between land and a river or stream]
Riparian zones are particularly susceptible to invasive plants species due to the natural processes associated with flooding and the favourable conditions of vegetative growth.
[Screen reads –Focus question: What are the natural processes of river systems, and how does the Cat’s Claw Creeper impact on them?]
[Screen reads -Riparian zones, particularly the vegetation adjacent to waterways, are experiencing particular decline across Australia. Riparian systems are important to maintaining both terrestrial and aquatic biodiversity.]
[Screen reads – Environmental weeds. Any other plant that causes or has the potential to cause negative environmental, social or economic impact]
The Cat's Claw Creeper is considered a major environmental weed in Australia. It was introduced to Australia as an ornamental vine but is now classified as a weed of national significance and a noxious weed.
[Screen reads – Cat’s Claw Creeper is a week of national significance and a noxious weed in Australia]
Prolific in South East Queensland and Northern New South Wales, the plant is conservatively estimated to cost $15 million to eradicate. The Cat's Claw Creeper has been included in the Global Invasive Species Data, the GISD, 2008. It has been listed as a noxious weed in South Africa and Australia.
Terry Moody [CEO and weed expert, Upper Clarence combined Landcare] – Now the cost of weeds to Australia is estimated about 10 billion dollars per year. Cat's Claw has a different impact. Most weeds that we recognise as weeds is because they interfere with something we do. So whether it be agriculture and agricultural productivity or just the sheer cost of controlling it.
[Screen reads – Ecology. Biology that deals with the relations of organisms to one another and to their physical surroundings]
It impacts agriculturally a little bit, but primarily it's impacting on the ecology and it's impacting on the rivers and the river systems, the water holes because once the trees go, the bank goes as well.
[Screen reads – Sediment. Matter that settles to the bottom of a liquid]
So you end up with all the sediment in the water holes, and your whole water ecology changes as well.
Narrator – Cat's Claw Creeper smothers tall trees, shrubs and ground cover, resulting in vegetation collapse and competition for resources. The plant is distributed efficiently by seed pods in the wind and water, making it especially problematic in river catchment areas where seeds can travel downriver. Persistent undergrowth tubers make physical removal difficult in well-established infestations.
Terry – Cat's Claw is a very large but still continuing-to-grow issue in most of the east coast of New South Wales and Queensland. So it actually goes from Gympie all the way down to the south coast of New South Wales, some in outlying places such as Melbourne and the Kimberley, would you believe, in Western Australia. So this is a vine that was introduced back into Australia in about the 1880s as a garden plant, which is common. Most of our weeds are actually garden plants that have escaped. It originally came from Mexico down to tropical South America.
[Screen reads – Cat’s claw creeper was introduced to Australia in the 1880’s as a garden plant]
So it's a vine that's quite happy in that area, and it is kept under control by the native insects and the native pests that it has in the area, but when it came here, it didn't have those pests. So it just started to go mad and it quite literally has gone mad in some areas and here is a case in point where it's actually climbed up all of the trees over the years. So it's quite an aggressive vine. It's called Cat's Claw Creeper because it has little cat's claws on it, and it'll stick and hang onto anything. Just amazing little three-fingered cat's claws on it.
So it'll grow up a tree, totally right up the trunk. It will go over then out all the branches and the sheer weight of those vines on the branches break the branches off the tree and you end up with a telegraph pole covered in vine. Then the weight of that eventually pulls that over because it dies because it can't photosynthesise anymore. So it dies, falls over, takes the creek bank with it. So that's why Cat's Claw is a weed.
Narrator – The main reason the Cat's Claw Creeper is a concern in riparian zones is the nature of its spreading. The vines and seed pods spread easily. Riparian zones are the areas where Cat's Claw Creeper are most likely to spread. It is in these areas managers will need to focus land management and control strategies.
List of sources and acknowledgements:
- Image – Map of Cats claw distribution. Based on map created by Weeds of national significance
- Video – Drone Footage of The Everlasting Swamp. We would like to thank The Everlasting Swamp National Park and Jessica Robertson Photography and Design for contributing their beautiful drone footage
- Narration – Voice over by Robert Llewellyn, New Soul Projects
- Acknowledgment – We wish to thank Father Pop Harry Walker, Annabelle Walker, Roy Bell, Jubullum Local Aboriginal Land Council, Steve Walker, Marty Walker, David Foley, Upper Clarence River Landcare, Terry Moody, Steven Ross, Frederick Ellis]
End of transcript