Robyn R. Watson
[Update of EMR feature – Watson R. (2009) Restoring the banks of the Namoi on ‘Kilmarnock’: Success arising from persistence. Ecological Management & Restoration, 10: 1 pp 10-19 https://onlinelibrary.wiley.com/doi/10.1111/j.1442-8903.2009.00434.x]
Figure 1. Casuarina (Casuarina cunninghamiana), River Red Gum and a range of grasses established on river bank at Kilmarnock after restoration works. (Photo R. Watson)
Riverbank restoration began on Kilmarnock in early 1990 with fencing the river area and planting native trees, shrubs and grasses. A program of killing the weeping willows resulted in their elimination by 2000. Tree lines were planted to connect the river corridor to natural conservation areas around the farm and this has resulted in a gradual increase in native wildlife leading to great environmental benefits both for the farm and surrounding areas.
Prior to the works the riparian zones on Kilmarnock had degraded to the extent that the banks were slumping during floods, with loss of old trees. This had arisen from decades of clearing, grazing and weed invasion. Since 2009 we can report that the fenced-off river corridor has continued to recover with native grasses beneath the trees, particularly Phragmites (Phragmites australis) and Vetiver Grass (Chrysopogon zizaniodes) which are growing well on the steep river banks (Fig 1). As the trees in the riparian corridor grew, additional tree lines were planted throughout the farm to connect the riparian zone to retained native vegetation areas and other set-aside conservation areas. This has led to an increase in native birds, micro bats and beneficial insect numbers.
Wildlife have returned to the area, including Little Pied Cormorant (Microcarbo melanoleucos) and Pied Cormorant (Phalacrocorax varius) nesting in the River Red Gum (Eucalyptus camaldulensis) trees one year. Flocks of Budgerigar (Melopsittacus undulatus) and Spotted Pardalote (Pardalotus punctatus) have been observed in the trees along the riparian zones. Pink Eared Duck (Malacorhynchus membranaceus), Musk Duck (Biziura lobata)(, Eurasian Coot (Fulica atra) and Brolga (Antigone rubicunda) visited wetland areas on the farm. There has been a noticeable increase in the small birds such as three different wrens including Superb Fairy-wren (Malurus cyaneus) and Variegated Fairy-wren (Malurus lamberti) and Australasian Pipit (Anthus novaeseelandiae).
The planted irrigated cotton crop was not sprayed with insecticide for 12 years after the increase in beneficial insect and bird numbers. Nest boxes have been installed in the conservation areas for the micro bats. Fourteen species of insectivorous micro bats have been recorded on the farm since the rehabilitation work began. Stubble quail (Coturnix pectoralis) have been nesting in the conservation areas.
Figure 2. Log groins with planted native trees established on steep river bend near Boggabri through the Namoi Demonstration Reach Project (2007-14) coordinated by the NSW Dept of Primary Industries. (Photo R. Watson)
Further works undertaken nearby. After seeing the improvement on our farm some adjoining landholders have begun fencing off their river areas and introducing rehabilitation measures on their farms. In one outstanding collective example, 120 kilometres of the Namoi Demonstration Reach Project was established by the NSW Dept of Primary Industries both upstream and downstream of Kilmarnock, from 2007 to 2014. This This involved contractors, working with permission of a number of landholders, planting over eight thousand trees and shrubs along the river and constructing log groins at a badly eroding river bend near the Boggabri township. These groins have worked well and have withstood a couple of small floods. The trees planted on the steep banks have also established well (Fig. 2).
Figure 3. – Planted Phragmites saved the river bank from bush fire in 2017. (Photo R. Watson)
A major bushfire in 2017 spread across the river to the top of the banks on the Kilmarnock side of the river. Because of the planted Phragmites on the river edge there was no damage done to the toe of the river bank (Fig 3) and we were able to bulldoze firebreaks to protect the planted trees affected from the fire.) However, a number of the old River Red Gums were badly burnt. Many of the very old hollow trees were killed by the fire but less hollow ones have begun to grow again, although this growth has been slowed by the present drought.
With the 2019 drought conditions the Namoi River has dried out, exposing the river bed. This has given me a chance to observe the river bed. I have been able to photograph and document the debris on the sand banks and the remaining water holes and show that there are now substantial amounts of hollow logs and debris (Fig. 4) which can provide good habitat for fish and water creatures when the stream is flowing.
Our family has purchased more land downstream on the Namoi River and we have implemented rehabilitation on the river banks, tree planting and conservation measures on those farms.
Contact. Robyn Watson, Kilmarnock, Boggabri, NSW 2382, Australia; Tel: 02 67434576 Email: wjwatson@northnet.com.au
Figure 4. Hollow log and debris on riverbed provide fish habitat when river is flowing. (Photo R. Watson)
EMR Project Summaries 