Agencies put their hardy heads together
Four Victorian agencies have been working quietly in the north of the state to stave off the extinction of one of Australia’s most endangered native fish, with impressive results.
Since 2014, the North Central Catchment Management Authority (CMA), Department of Environment, Land, Water and Planning (DELWP), the Arthur Rylah Institute (ARI) and the Victorian Environmental Water Holder (VEWH) have been carefully managing Lake Elizabeth near Kerang, using water for the environment to create suitable habitat and conditions to allow for the establishment of the Murray hardyhead.
Murray hardyhead is a small native fish that was once widespread in rivers and wetlands of the lower Murray-Darling Basin.
“The species has suffered a severe decline, with less than 10 populations remaining in the Basin, and the world,” North Central CMA Project Officer Amy Russell said.
“Only two of these remnant populations exist in Victoria, one in the Swan Hill region and the other near Kerang.
“We are trying our best to prevent further localised extinctions, and to increase their numbers by finding new wetland habitats for the species.”
In 2015, a small number of fish were moved to Lake Elizabeth in an attempt to establish a viable population.
“Lake Elizabeth’s elevated salinity and abundant plant life provided us with an opportunity to create beneficial conditions for them,” Ms Russell said.
“Before any fish could be placed into Lake Elizabeth, we needed to get the habitat conditions and salinity levels right.
“Through deliveries of water for the environment, we were able to bring the salinity level down considerably, but still keep it high enough to keep predators such as carp out.
“This has also promoted aquatic vegetation growth and increased the amount of zooplankton present, an important food source for Murray hardyhead.”
Water for the environment was first delivered to Lake Elizabeth in 2014, and fish were placed in the lake a year later.
“Murray hardyhead only live to about 18 months, so it was important we had conditions right for them to breed once they were released into the lake,” Arthur Rylah Institute Fish Ecologist Daniel Stoessel said.
“We were not sure how long it would take to see if the relocation worked. It’s a huge lake, the fish are tiny and we only released a small number.
“When we visited in April this year, we were surprised at what we found. We quickly put a net in and immediately found 24 Murray hardyhead. That is an outstanding result and one we are all very excited about.”
Ms Russell said the results couldn’t have come at a better time.
“Everyone has been working really hard over the past four years, and this result shows how successful relocation can be,” she said.
“This has given us even more impetus to work together and keep this critically endangered species from extinction.”
Water for the environment is prioritised by the Victorian Environmental Water Holder (VEWH) in line with its Seasonal Watering Plan. The VEWH Seasonal Watering Plan is available for download from www.vewh.vic.gov.au, with regular watering updates posted on the North Central CMA website here.