Summary

Despite being the basis of a popular recreational fishery in many areas, and a threatened species across much of its range, little research undertaken on the biology, status or potential threatening processes of Murray crayfish has been published. This scoping study reviewed and assimilated all available published and unpublished knowledge on the species, identified key knowledge gaps and made recommendations relevant to its sustainable management.

A large volume of unpublished data on many aspects of Murray crayfish existed and were summarised, including data on morphology, systematics, distribution, population genetics, habitat requirements, environmental tolerances, movement and migration, daily and yearly activity patterns, diseases and parasites, population biology (such as breeding biology, the sex ratio, growth, age and mortality) and the population size structure and abundance of several populations. Less information on the impact of various threatening processes is available, generally because the declines occurred several decades ago. However, although some threatening processes which may have resulted in declines in the past are no longer impacting on Murray crayfish populations, others continue to affect populations, either resulting in continuing declines, or limiting the recovery of Murray crayfish populations that declined historically. The study also reports on a series of consultations with representatives from Aboriginal communities throughout the Murray and Murrumbidgee catchments undertaken to document traditional knowledge and the use of the Murray crayfish by Aboriginal people.

Information on the current status or Murray crayfish throughout their entire range remains the most significant knowledge gap for the species. Other high priority knowledge gaps that may assist with appropriate management of the species include data on the habitats and biology of juvenile crayfish, the impact of habitat alteration and the effects of pesticides and sedimentation.

Management recommendations arising from the scoping study include, a review of recreational fishing regulations (with inter-state consistency), the establishment of an ongoing monitoring program for Murray crayfish, an enhanced community education strategy and a review of the national and international conservation status of the species.