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Summary

• Current Species Status
• Habitat Requirements and Limiting Factors
• Recovery Objectives
• Overall Objective
• Specific Objectives
• Recovery Criteria
• Actions Needed
• Estimated Cost of Recovery
• Biodiversity Benefits

Current Species Status

Endangered on ESP and ANZECC lists. Categorised as Endangered in Action Plan (Wager & Jackson, 1993), currently listed as Endangered on IUCN Red List, assessed as Critically Endangered against 1994 IUCN criteria by Wager & Jackson (1993) and Brown et al, 1998. Area of occupancy has declined by greater than 80% within the last three trout cod generation intervals.

Habitat Requirements and Limiting Factors

Stream positions occupied by trout cod are characterised by a high abundance of large woody debris in the immediate surrounds and extending up into the water column, in water that is comparatively deep, comparatively close to the bank and to the maximum river cross-sectional depth. These requirements are more specific than for other large freshwater species in the Murray River. As a result of desnagging, this habitat type is patchily distributed and limited in availability. The availability of appropriate snag habitat is considered to be the primary limiting factor for trout cod. The absence of well developed strategies for re-introduction is a major factor preventing effective restocking of suitable habitat to establish populations of a size and density that can become self-sustaining.

Recovery Objectives

Overall Objective

To obtain down-listing of trout cod from Critically Endangered to Vulnerable within 25 years

Specific Objectives

1. To manage and manipulate habitat conditions in the Murray River to stabilise the existing population at a self-sustaining level.
2. To increase the species' distribution by re-establishing populations of suitable size and density within available habitat areas within its former range in the Murray and Murrumbidgee systems.
3. To manipulate the Seven Creeks population by relocation of individuals within the system to enable continuing trout cod recruitment within suitable habitat areas.

Recovery Criteria

1. Within 8 years, Murray River habitat availability has been improved, the population is stable and displays the characteristics of a self-sustaining healthy population.
2. Within 6 years, the range of the species in which breeding occurs has been extended to include an additional 4 sites within the Murrumbidgee and Murray river systems.
3. Within 5 years, trout cod recruitment occurs throughout suitable habitat areas of Seven Creeks.

Actions Needed

1. Management of Recovery Program
2. Planning for multiple species recovery
3. Population and Habitat Viability Modeling
4. Management of the Murray River, Seven Creeks and re-introduced populations
5. Captive breeding and re-introduction
6. Rehabilitation of instream habitat
7. Community and interstate co-operation

Estimated Cost of Recovery

Biodiversity Benefits

Trout cod in the Murray River and its major tributaries is part of a fish community in which several members are under threat. The development of population and habitat models for trout cod will provide important benefits for these species. Equally, the development of effective procedures for re-introducing trout cod will have major benefits for Murray cod, golden perch and Macquarie perch. Continuing investigation of the environmental requirements of trout cod in the Murray provides additional data on the sympatric species.