Irenepharsus trypherus (Illawarra Irene) Recovery Plan

NSW Department of Environment and Conservation, 2005
ISBN: 1 7412 2145 5

Executive Summary

This document constitutes the formal Commonwealth and New South Wales State Recovery Plan for Irenepharsus trypherus (Illawarra Irene), and as such considers the conservation requirements of the species across its known range.  It identifies the future actions to be taken to ensure the long-term viability of I. trypherus in nature and the parties who will carry out these actions.

Irenepharsus trypherus is listed as endangered on the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 and as endangered on the NSW Threatened Species Conservation Act 1995.  It is an annual or short-lived perennial herb (family Brassicaceae) that occupies steep rocky slopes and cliff lines at the ecotone of sclerophyll forest and rainforest.  It is known historically from 17 sites in the Illawarra and Shoalhaven regions of NSW.  Ten of these sites are located on freehold land while seven sites are located within conservation reserves.

The total population size of I. trypherus is estimated to be 1120, comprising at least 267 mature individuals.  Considerable fluctuations in population size have occurred at individual sites over time, and these fluctuations are considered to be at least partially a natural response of this short-lived, opportunist species to prevailing environmental conditions.

Threats recorded at I. trypherus sites include habitat clearance, weed invasion, erosion, and herbivory and trampling by livestock and feral/native animals.  The extent and intensity of the threats operating at some sites remains poorly understood.  The failure to locate the species at four of the eleven sites surveyed during the preparation of this recovery plan indicates that recent local extinctions may have occurred.

The overall objective of this recovery plan is to provide for the continued and long-term survival of I. trypherus in the wild by preventing the loss of populations of the species.  The specific recovery objectives are:

  • To prevent the loss of sites through land-use change;
  • To identify and manage the threats operating at sites that contain the species;
  • To establish the extent of the current distribution of the species;
  • To provide the community with information that assists in conserving the species;
  • To raise awareness of the species and involve the community in the recovery program;
  • To promote research that will assist with the management of the species;
  • To implement an ex-situ conservation program for the species.

It is intended that this recovery plan will be implemented over a five year period.  The total cost to implement the plan is $81,500 over five years although this does not include site management costs, as these costs are yet to be determined.

Lisa Corbyn
Director General

Bob Debus MP
Minister for the Environment