The second largest freshwater crayfish, the second largest in the world, once inhabited a lot on the longest river Australia. We have regained it.

The crayfish on the Malay river is always completely protected, and if you catch it, you have to return it to water immediately. Credit: South Australia
Malay crayfish used to prosper in the southern part of the Malay Darling Basin. This kind was seen everywhere, from the headwaters of the Australian Alps and the headwaters of the Malan Biji River to Wellington, South Australia.
For thousands of years, indigenous people have managed the harvest in a sustainable way. However, after the reconciliation in Europe, crayfish inventory has fallen. This was partially due to commercial and entertainment harvesting that began in the late 1860s. At the peak of 1955, 15 tons of Malay crayfish were captured from the River in New Southwales and sent to the Melbourne and Sydney market.
In Southern Australia, commercial fisheries became impossible by the 1960s, and this species was no longer targeted. In the 1980s, Malaye Slayfish became a state protection species. However, the damage has occurred.
The problem was not only overcharge. Malay crayfish is struggling with the use of dams and weirs to adjust the flow of the river to adjust the flow of the river. Poor water quality, including pesticides and other pesticides, worsened the situation.
Malay crayfish has disappeared from South Australia at the past 40 years. A five -year -old survey could not find anywhere in the state.
However, the situation has changed in the winter of 2023, when the re -introduction program began. Currently, we are preparing for the third release of crayfish, but there are significant signs that many crayfish from the previous release are still performing well.
Seeds that require support
Like many species of the genus youthacas, which is very extinct crisis, Malay See crayfish grows slowly. It takes almost 10 years for a female to mature sexually, and the number of eggs to be laid is small. Shake is also limited. For this reason, recovery of the population is difficult in both numbers and range.
In response to recent evaluations, EUASTACUS Armatus species are expected to be listed as an endangered species under the Australian Nature Protection Law.
In order to help the species recovery, it will be necessary to maintain a reconstruction and other preservation activities.
A long time has passed, formed by adversity
The idea of returning Malaye crayfish to the river in South Australia is not a new one.
The Adelaide University ecologist, the late Keith Walker and Mike Gedes, proposed this for the first time in the 1990s. They even put crayfish in a cage to show that some of the rivers are suitable for crayfish habitat.
And in 2007, the idea of re -introduction emerged again. This was one of the major recommendations in the report that identifies the gap between knowledge about this species.
However, this idea gained momentum after the disaster. From 2010 to 2011, a wide range of floods occurred in the southern part of the Malay Darling Basin, causing a “low oxygen black light” phenomenon. This is a place where fallen leaves and rubble in flooded prones flow into the river, reducing oxygen levels, causing mass death of fish and crayfish.
This has influenced further research on crayfish genetic, recovery, and preferred habitat. This was a guideline for the 2019 strategy that outlined how this species would succeed in re -introduction. The five -year trial re -introduction program in this kind of New Southwales has helped to sophisticated strategies.
Later, from 2022 to 2023, another Malay black water event occurred in New Southwales and Victoria, and crayfish was pushed up from water to riverbank.
The community responded by seeing a dying crayfish out of the water and seeing the predators to be eaten or being hooked by humans. Under the guidance of fisheries and fisheries protection charity, they rescued crabs and kept them safely at fishery farms until they returned to wild.
Many of these crayfish were later returned to the original river. However, as part of a new re -introduction program, a small number was pending to be released to SA.
As a true cooperative initiative, Nature Glainelg Trust, a small environmental non -profit organization, cooperates with natural resource management agencies, indigenous communities, three states, and private fishery aquaculture facilities. Is realized. 。
Signs of positive crayfish due to the release of crayfish
Malay crayfish was first released to South Australia in the winter of 2023. This was a big moment for those who have defended this kind of resurrection for many years.
In the winter of 2024, 200 crabs were released.
Each time it was released, some crayfish had tracker tags. We provided the world’s first movement and activity information. This indicates that all the tagged crayfish are regularly detected, indicating that crayfish is prosperous.
In a seasonal survey of each season in the re -introduction area, it has been confirmed that this species is alive, and it will be Malay crayfish that has been discovered for the first time in more than 40 years.
Resurrection of totem and symbolic seeds
The re -introduction of Malay crayfish in Riverland, South Australia, is also culturally important both culturally and ecologically important.
This indicates that the important totems have returned to the Erwiling tribe in this area and provide a way to connect to this species.
Retunging this kind of individual group in Southern Australia, where the hypoxic black water phenomenon was not so serious, it is also an insurance for extinction.
This species is considered to be a keystone species, meaning that it plays a major role in ecosystems. Therefore, returning to the river may result in greater greater ecological benefits.
The first step of many steps
Successful re -introduction programs require continuous initiatives. In the next few years, it will be necessary to add it to the individual groups that will re -introduce crayfish.
The re -introduced individuals will continue to be monitored to confirm that the number is increasing and the range is expanding. It will continue to be protected from fishery by local fishery authorities.
If successful, further re -introductions may occur in other regions in South Australia.
Providing the Kanbacation
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