Document ID: chunk:federal_register_of_legislation:F2022L00677:reg:12:p17
Version: federal_register_of_legislation:F2022L00677
Segment Type: reg
Provision Reference: reg 12 (pt 17/33)
Character Range: 50020–53426

elevated levels of various contaminants around southwestern Australia, including Mercury in Cockburn Sound and Selenium in the Albany waterways (Dunlop et al. 2013). At the remote Abrolhos Islands, the binders in fabricated plastics (phthalates) were present in the preen gland secretions of 49 per cent of the Australian Fairy Terns sampled (Dunlop 2018). Phthalates are potent pseudo-oestrogens capable of interfering with sexual development and reproduction.

         2.2.8     Hybridisation
   Hybridisation has been recorded between Australian Fairy Terns and Little Terns in South Australia (Cox and Close 1977), Victoria (Norman et al. 1996), New South Wales (Ross et al. 1999) and Tasmania (E.J. Woehler unpubl. obs.). Further interbreeding may diminish the genetic distinctiveness of both species (Ross et al. 1999).
   Interbreeding between Little and Australian Fairy Terns is particularly problematic in New South Wales where Little Terns are listed as Endangered under state legislation. Appropriate management interventions are required to discourage hybridisation, predominantly in New South Wales.

                   2.3            Threat prioritisation

             Each of the threats outlined above has been assessed at expert workshops to determine the risk posed to the Australian Fairy Tern population using a risk matrix. This, in
             turn, determines the priority for actions outlined below. The risk matrix considers the likelihood of an incident occurring and the consequences of that incident. Threats may act differently in different parts of the species range and at different times of year,
             but the precautionary principle dictates that the threat category is determined by the subpopulation at highest risk. Population-wide threats are generally considered to present a higher risk.

             The risk matrix uses a qualitative assessment drawing on peer reviewed literature and expert opinion. In some cases the consequences of activities are unknown. In these cases, the precautionary principle has been applied. Levels of risk and the associated priority for action are defined as follows:
               •       Very High – immediate mitigation action required
               •       High – mitigation action and an adaptive management plan required, the precautionary principle should be applied

               •       Moderate – obtain additional information and develop mitigation action if required

               •       Low – monitor the threat occurrence and reassess threat level if likelihood or consequences change

             TABLE 2 Risk prioritisation
                 Consequences
Likelihood of
occurrence
Not significant  Minor         Moderate  Major      Catastrophic
Almost certain   Low           Moderate  Very High  Very High     Very High
Likely           Low           Moderate  High       Very High     Very High
Possible         Low           Moderate  High       Very High     Very High
Unlikely         Low           Low       Moderate   High          Very High
Rare or Unknown  Low           Low       Moderate   High          Very High

Categories for likelihood are defined as follows:
     •       Almost certain – expected to occur every year
     •       Likely – expected to occur at least once every five years
     •       Possible – might occur at some time

     •       Unlikely – such events