Native Fish Forum 2017

There’s a new video out that explains how native fish in the Murray ̶ Darling Basin respond to flows and what it means for recreational fishers.

Following on from the Native Fish Forum 2017, we’ve been working with the NSW Department of Primary Industries Fisheries to produce the video which you can view here.

There are also some great infographics that help tell the story about native fish and flows available from the DPI Fisheries Fish and Flows webpage.

Help spread the word by promoting these new communication products among your networks and contacts.

The presentations from the MDB Native Fish Forum are now on YouTube.

Check them out and share with your colleagues.

Native Fish Forum on YouTube

The 2017 Murray-Darling Basin Native Fish Forum was a great success!

Thank you to our sponsors, and all of the attendees, presenters and organisers for making the forum such a great event.

Congratulations to Rod Price (NSW DPI Fisheries) and Kate Scanlon (MDBA) on their excellent coordination of the forum.

Thanks also to the organising committee: Rod Price, Craig Copeland (NSW DPI Fisheries), John Koehn (Arthur Rylah Institute), Qifeng Ye (SARDI), Damian McRae (CEWO), Michael Hutchison (Qld DAFF) and Heleena Bamford (MDBA); and the communications group: Rod Price, Boni Brown (OzFish), Terry Korodaj (NSW OEH), Katrina Willis, Beatrix Spencer and Stu Little (MDBA).

Don’t forget to keep an eye on this site for videos of the presentations and new stories and links to native fish info from around the Basin. Keep the conversations going by using #mdbnativefish and sharing information with others.

In the meantime, check out Rod's thoughts on the forum (video on right) and some of the feedback we captured on the day (click on the article title to open this story in full):

Comments are welcome on any of the content on this site, and anything you heard at the forum.

Lamprey are an eel-like fish that spend most of their adult life at sea, moving into rivers and migrating upstream when it’s time to spawn.

Lamprey numbers in the Murray-Darling Basin have declined due to barriers to migration and reduced river flows. When there is no flow through the Murray barrages during winter and early spring, they can’t swim in from the ocean and up the river.

Fishways installed at the barrages and the locks and weirs along the River Murray have provided lamprey, and other migratory fish, with a continuous path from the sea to Hume Dam or from the sea to Menindee Lakes.

But we don’t know where lamprey go to spawn. When we do, we can work out how to manage river flows to support lamprey breeding.

The South Australian Research and Development Institute, supported by the MDBA and Basin governments, is using the PIT (Passive Integrated Transponder) receiver system installed on each fishway to track lamprey movements.

This work is showing that lamprey move hundreds of kilometres upstream. The PIT system, however, can only tell us which fishways lamprey have passed through, it cannot tell us if lamprey have swum up a tributary or into an anabranch.

Acoustic transmitters and listening stations are now being used to provide a better picture of where these mysterious creatures go.

During July and August, pouched lamprey (Geotria australis) have been trapped at the barrages, acoustic tags have been attached and the lampreys released.

A network of receivers will record the signal of each tag and scientists will analyse the data to determine where lamprey may be heading to.

The network of receivers is also helping scientists understand fish movement in other regions of the river. A number of tagged fish from other studies have been detected in the Murray and Darling rivers, having moved hundreds of kilometres away from where they were being studied.

Flows to support lamprey are included in the 2017 environmental watering priorities prepared by the MDBA. For further information on basin-wide environmental watering priorities, visit:

https://www.mdba.gov.au/managing-water/environmental-water/priorities/native-fish

Golden perch travel thousands of kilometres across the Murray-Darling Basin (MDB) during a lifetime and their ear bones can tell us where they were born and where they’ve been.

Understanding their movements can help us manage flows to better support healthy populations of golden perch, one of the most popular recreational species in the Basin.

Otoliths are a bony structure within the ear of fish. Because they are made up of daily deposits, like tree growth rings, they can help us understand how old a fish is.

Water flowing in different rivers has a specific chemical signature and these chemicals are absorbed into the otolith’s structure. As a fish moves, the chemical signature of the otolith also changes.

Otoliths of golden perch are telling us a very interesting story thanks to the work of the South Australian Research Development Institute (SARDI), funded by different government agencies including by MDBA.

Changing chemical signatures in golden perch otoliths show that:

• eggs and larval golden perch drift hundreds of kilometres downstream, hopefully washing into nursery habitats

• when flows are right, young fish swim upstream or downstream for hundreds or thousands of kilometres over months to years

• once young fish become adults, they may migrate upstream to lay eggs and start the cycle again.

Just prior to the end of the Millennium drought high flows in the Darling River led to a major golden perch recruitment event in the lower Darling region. Subsequent flooding across the whole basin the following year triggered young golden perch to disperse in many directions.

Fish with lower Darling origins have been found in the mid-Murray River, the Goulburn River, the Edward-Wakool, and the lower Murray, including the Lower Lakes

A similar, large-scale breeding event has occurred in the Darling River in 2016-17 (keep an eye out for an upcoming story about this).

The 2017-18 environmental watering priorities look to capitalise on these large-scale events by providing dispersal flows in the major rivers and tributaries of the southern MDB.

For further reading on the golden perch otolith research, visit:

http://www.finterest.com.au/natives-and-introduced/fish-detectives-investigating-the-secret-life-of-golden-perch/

For further information on basin-wide environmental watering priorities, visit:

https://www.mdba.gov.au/managing-water/environmental-water/priorities/native-fish

It turns out that most silver perch in the Murray River live a whole decade less than previously thought.

This means they have less time to breed, making it important to create the right conditions to support them as often as possible.

Silver perch are nationally listed as critically endangered but they were once the most widespread of the native fish species in the Murray-Darling Basin.

Like many plant and animal species in the Basin, their numbers have declined dramatically due to river regulation, storages and increased water consumption for towns, agricultural and other economic activity.

Scientists thought silver perch lived up to 17 years of age in rivers and creeks but new research has found that most fish in the Murray River live only to seven years of age.

Silver perch reproduce from three years old. Now we know the window for breeding is so much smaller it means that if conditions are unsuitable for more than a year or two in a row, silver perch in the Murray would be under serious threat.

When this new research undertaken by the Arthur Rylah Institute and funded by the MDBA emerged earlier this year, we recognised the risk and acted. The 2017 environmental watering priorities include the need for suitable flows for silver perch every year.

The 2017 priorities also include additional flow measures that can help distribute and build silver perch populations in other suitable habitats.

Environmental water holders and water management agencies are working together to deliver the flows silver perch need for healthy populations. For example, flows in the Campaspe and Goulburn rivers have been effective in dispersing silver perch to new habitats.

For further information on basin-wide environmental watering priorities, visit:

https://www.mdba.gov.au/managing-water/environmental-water/priorities/native-fish

Flow has a major influence on the life cycles of native fish, and different species respond differently to different flows.

Flow triggers spawning, fish movement along rivers, and breeding. Flow isn’t the only thing needed but without the right flows at the right time, fish populations can’t be sustained.

Returning suitable flow conditions is a key action that can help native fish.

The environmental water planning team here at the MDBA work closely with scientists to understand the flow and connectivity requirements that will benefit native fish, and build strong populations across the Murray-Darling Basin.

To help water managers deliver suitable flows for fish, we have identified three Basin-wide environmental watering priorities.

The priorities aim to:

• reinstate flows that promote life cycle processes across the southern connected Basin

• improve flow regimes and connectivity in the Barwon–Darling river system

• support threatened native fish and build on opportunities to expand the area in which they occur

For further information on basin-wide environmental watering priorities, visit:

https://www.mdba.gov.au/managing-water/environmental-water/priorities/native-fish