Did you know that in 1986, NSW Fisheries found that there were zero native fish in the Yass River?

This is the issue Ross Webster, along with NSW Environmental Trust, Yass Landcare Group and Yass Valley Council aim to rectify, an issue caused by invasive plant and fish species along the Yass River and Manton Creek. A total of two kilometres of invasive plants were recently cleared from the area, with a celebration BBQ held at Hardwicke for their efforts. Ross Webster, co-organiser of the events, reached out to the Yass Valley Times to discuss the ongoing issue and what has been done so far. 

 

“It’s ongoing work, an ongoing battle to keep them from spreading…They’ve just swamped our native environment.” 

 

The invasive flora removed included commonly found plants, such as Basket Willow, a tree-like plant, as well as Hawthorn, a fruit-bearing shrub, Wild Plum and Blackberry bushes from the Yass River and Manton Creek systems. Local government sectors assisted with finance and direction, with NSW Environmental Trust, Yass Valley Council and Yass Landcare Group actively involved. 

The removal of these species amounted to a four-week effort, thanks largely to C J and M M Beck Tree Removal Specialists. The plants were stacked for burning, adhering to a strict policy imposed by Local Government to ensure the safety of the river’s stability.

On the invasive fauna, with Basket Willow in particular, Ross said,

“They are exotic to the Australian environment, and are classed as weeds, invasive weeds. The willow, for example, takes a huge amount of water from the system because it’s such a big tree with lots of foliage on it, and it excludes the sunlight from the banks of the rivers, so it creates a lot of problems in that nothing will grow near them” said Ross, commenting further that the issue has the potential to spread.

 

“The drop seeds stretch hundreds of miles through the water — They’ll end up extending all along the waterways. They exclude a lot of things.” Ross is concerned not only by the extent to which the invasive species can travel but with how easy it could be to do so, requiring little effort. 

 

“It propagates and spreads very easily, through cross-pollination, drop offs, and then just grows in the water and lodges in the banks”, explained Ross. 

 

The CSIRO estimates it only takes five litres of water to sustain it for a half-sized willow, hence the urgency behind removing these invasive species. The removal of willows is being carried out right across NSW, especially in the waterways that lack water. Ross states these efforts have “Returned 12 megalitres of water from removing the willows.” 

 

Native fauna is not the only group at risk from the presence of exotic fish and plants, as the introduction of European and Asian Carp has destroyed the local fish ecosystem, a problem also shared in other areas such as Canberra. Commenting on the risk posed to fish and animals in the area, Ross explained;

   “The Murray Cod, Yellowbelly fish  and native other species, they lay their eggs around and against the red river gum or our native woodwork. They don’t propagate in areas that are infested with willows”, said Ross. 

 

The celebration BBQ was held in thanks and acknowledgement of the teams’ efforts, with Ross quoting around twenty-five attendees present at Hardwicke.

Restoring the Riparian Corridor of the Yass River & Manton Creek Celebration BBQ

Commenting on why the issue was important to him and the others, Ross said,

“It’s basically landcare, I’ve been involved with landcare for thirty years, and its been an ongoing commitment to restore our systems to the way they used to be” 

 

Griffin Palen