A Koala Corridor for Raymond Terrace (written by Raymond Terrace Landcare group)
Raymond Terrace Landcare Group started over twenty years ago as a volunteer Group with Port Stephens Council called Raymond Terrace Parks, Reserves and Tidy Towns. Working with the Council enabled us to undertake bush regeneration on Council land, and in return, we had access to support, such as advice and resources.
Over the past few years, our group has participated in Landcare events, such as Creating Habitat for Wildlife and Schools National Tree Day in Boomerang Park at Raymond Terrace. Hunter Region Landcare Network (HRLN) has also provided our group with excellent support, including information and submission-writing for our projects. Consequently, our group joined HRLN to continue receiving inspiration and assistance with our work.
National School Tree Day in the Park
The Group’s goal is to restore the wildlife corridor connecting Boomerang Park, Muree Golf Course, and Council land along the Grahamstown Canal, including Elizabeth Reserve, Martens Avenue and Anderson Oval. Once we have completed these sites, we will continue planting habitat along the full length of the Canal.
Map of Raymond Terrace Wildlife Corridor Restoration Project. (Source: Six Maps https://maps.six.nsw.gov.au.apps)
Key
Ongoing restoration sites (red)
Grahamstown Canal (blue)
Potential corridor restoration areas (yellow)
Wildlife underpass with koala posts over fences (pink)
Muree Golf Course (white boundary)
The decline of wildlife and its habitat
Boomerang Park and Muree Golf Course contain a preferred habitat for koalas and local birdlife. For example, Muree Golf Course has giant Tallowwoods and other native trees, making it a recognised koala sanctuary for the release of sick and injured koalas and other wildlife. Over the past sixty years, the community has regularly planted native vegetation as habitat in Boomerang Park.
The Australian Koala Foundation mapped preferred koala habitat along the Canal several years ago; however, at present, there are only about 10% of the mature koala food trees surviving in the low-lying wetland areas along the Canal, with about 60% being mature Melaleuca quinquenervia and 30% being mature Camphor Laurel and other noxious species.
The Grahamstown Canal fills the surrounding Melaleuca quinquenervia forest wetlands in Elizabeth Reserve with water for several weeks after heavy rain. This flooding killed about 50 Swamp mahogany trees planted by volunteers a few months earlier.
Grahamstown Canal in flood
Threats to this wildlife corridor include soil disturbance from the construction of the Grahamstown Canal, the Raymond Terrace Bypass, and the shared pathway. This disturbance has contributed to the infestation of noxious weeds, including Camphor Laurel, Narrow-leaf Privet, Castor Oil Plant, and Wild Tobacco trees. Unfortunately, the Camphor Laurel trees have invaded the root systems of mature Swamp Mahogany trees and have also prevented the regeneration of endemic species in the corridor, further reducing the area’s biodiversity. The presence of mature Camphor Laurels has created a vast seed bank that continually sprouts new seedlings.
Mature Narrow-leaf Privet has also invaded our project area. Unfortunately, Narrow-leaf Privet and the Camphor laurel can successfully grow close together and outcompete the regeneration of endemic species. The Narrow-leaf Privet produces prolific amounts of seed, which birds will spread to other areas. The seeds that drop in the forest will also contribute to the noxious weed’s seed bank.
Camphor Laurels invade a large Swamp Mahogany Tree
The Narrow-leaf Privet invades our Paperbark forest
In addition to the above weeds, you will find a high population of Wild Tobacco trees, Lantana, and Morning Glory, all of which harm the endemic ecosystem in the Reserve.
Morning Glory and Castor Oil Plants growing over and around Melaleuca quinquenervia trees
Furthermore, the bypass has fragmented the wildlife corridor, preventing 17 female koalas at the Muree Golf Course from breeding because male koalas were unable to cross the bypass. Consequently, koalas in the golf course died from old age with no offspring. The construction of the M1 Extension to Raymond Terrace has removed vast amounts of vegetation for the motorway. For example, the construction of the M1 removed vegetation 600 meters south of the wildlife corridor, including Eucalyptus parramattensis, a koala food tree, and Callistemon linareifolius, both threatened species.
Making a Difference:
Our group aims to increase biodiversity in this area by: a) removing fruit from weeds and binning them to prevent germination. b) pulling out weeds with minimal soil disturbance, or, if this is not possible, using a minimal amount of herbicide instead. c) conducting follow-up weeding of seedlings and suckers.
Volunteers are pulling out a wall of Lantana at the Martins Avenue Site while keeping the soil intact
The second step has been using the ‘Trees Near Me’ and the ‘Restore Trees NSW’ apps to identify indigenous fauna and flora for the corridor. Hence, selecting plants that will provide food and habitat for wildlife throughout the seasons, and replanting what we have lost, such as Callistemon linearifolius and Eucalyptus parramattensis. A licensed seed collector in our group obtained native seeds from the doomed Callistemon linearifolius in the path of the M1. These seeds were grown into plants and planted in the wildlife corridor by our volunteers.
Volunteers germinated these Callistemon linearifolius and planted them in the corridor
Volunteers at the Council’s nursery preparing trees in pots for planting on our project site
To improve koala habitat, volunteers planted Swamp Mahogany trees along the Canal and on the Golf Course
By considering the concerns described earlier, we have improved the survival rate of trees we plant by:
- Only planting larger trees in tree cages so herbivores can’t eat the canopy.
- We consider climate change by avoiding deep-stem planting in clay and placing the tree away from deep flood zones.
- Installing agricultural pipe around the roots when planting for deep and efficient watering.
- Applying a Mycorrhiza blend under the root ball when planting to promote root growth, improve drought and disease tolerance, and provide other benefits.
- Frequent follow-up watering, weeding, and removal of invasive grubs and insects in the first six months.
- Place wet cardboard around the plant when planting and cover it with wood chips to prevent weeds from growing.
To improve the functioning of the wildlife corridor under and around the Raymond Terrace Bypass twin bridges, we worked with Transport for NSW and Port Stephens Council to install four koala escape posts along the fencing around the twin bridges. These posts will help koalas access their preferred habitats at Muree Golf Course and Boomerang Park.
Recently installed Koala escape posts
Future Improvements:
- Expand the weed-control target area to the full length of the Grahamstown Canal.
- Given that we have hundreds of mature Camphor Laurels and Narrow-leaf Privet to control, we wish to acquire an Injector-400 – Di-Bak Tree Control Capsule Applicator with capsules and plugs from Adama Australia Pty Ltd. This Injector will reduce the amount of herbicide we use along the Grahamstown Canal by 30% and eliminate waste from non-target use and cleaning.
- Recruit more volunteers.
- Implement biocontrol methods as they become available. For example, it is possible that the lace bug could control Narrow-leaf Privet, provided future research does not detect that this bug poses a threat to native privet or other plants.
Everyone is welcome to attend our Friday morning working bees with morning tea.
Please call Coral on 0408 358 691 for more information.