Bugs reveal poor river health
A snapshot of river health in the north central catchment region has found a number of rivers and streams are in poor ecological health.
About 50 volunteers measured the condition of the Little Murray River, Loddon River, Gunbower Creek and Box-Pyramid Creek, creating a baseline snapshot of the health of the waterways.
The comprehensive wide-scale citizen science monitoring project measured the health of the four waterways by measuring the kind of waterbugs present.
North Central Catchment Management Authority project manager Nicole Bullen said the type of waterbugs in a river told us a lot about its health.
‘‘If there is a large diversity of waterbugs, the river is generally in better shape,’’ Ms Bullen said.
‘‘Low numbers of certain waterbugs can indicate an ecological disturbance, and we can also get an indication of pollution levels by what sort of bugs are present.’’
Nine sites were monitored in the lower Loddon River and overall scores indicated the system did not meet agreed standards for ecological health.
Macroinvertebrate communities in the lower Loddon River have likely been affected by a highly altered flow regime, decreased over-bank flooding, poor water quality (such as high turbidity and low dissolved oxygen levels), degraded habitat from infilling of pools with sediment, and poor riparian condition through past clearing and stock access.
Though in-stream woody habitat densities upstream of Kerang Weir are near natural levels, there are areas downstream of the weir that have been channelised and desnagged in the past.
Where riparian improvements have been delivered in the Loddon system, the water quality and macroinvertebrates may take time to recover to a good condition.
Ms Bullen said Waterwatch volunteers, as well as recreational anglers, took part in the monitoring.
‘‘The data provides a baseline assessment of river health with fish in mind,’’ she said.
‘‘Healthy rivers mean healthy bugs, which leads to healthy and abundant native fish, and we know a century of regulation has changed fish numbers dramatically.
‘‘We know that years ago people were asking which kind of native fish their family would like for dinner before they went fishing and the Murray River Fishing Company was pulling tonnes of fish out of the river every week.
‘‘Things have changed, and this snapshot has shown that these waterways are in poor health, with all but one recording a unanimous severely impacted rating.’’
Ms Bullen said the snapshot will now be used as baseline data to measure the impact of the North Central CMA’s Native Fish Recovery Plan, a plan to restore the quality of the waterways and their native fish populations.
Ms Bullen said it was important the local community continued to be involved in monitoring the sites.
‘‘We want to hear from anyone keen to help out and become volunteers. We will provide them with training and all the equipment they need,’’ she said.
‘‘They will help us make a big difference to the quality of their local creeks and rivers.’’ ■ To volunteer, phone 5448 7124 or email: firstname.lastname@example.org
Help needed . . . North Central Catchment Management Authority is looking for volunteers to assist in monitoring river health in the region.