Document ID: chunk:federal_register_of_legislation:F2022L00677:reg:12:p18
Version: federal_register_of_legislation:F2022L00677
Segment Type: reg
Provision Reference: reg 12 (pt 18/33)
Character Range: 53172–56682

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 are known to have occurred on a worldwide basis but only a few times

     •       Rare or Unknown – may occur only in exceptional circumstances; OR it is currently unknown how often the incident will occur

Categories for consequences are defined as follows:
     •       Not significant – no long-term effect on individuals or populations
     •       Minor – individuals are adversely affected but no effect at population level
     •       Moderate – population recovery stalls or reduces

     •       Major – population decreases
     •       Catastrophic – population extinction

   TABLE 3 Australian Fairy Tern residual risk matrix
Likelihood of  occurrence
                           Consequences
Not significant            Minor         Moderate       Major                                             Catastrophic
Almost certain                           Hybridisation  Native wildlife                                   Disturbance Invasive species
                                                        Habitat degradation and loss of breeding habitat  Climate variability and change
Likely                                                  Water management and increased salinity
Possible                                 Pollution
Unlikely
Rare or Unknown

               Chapter 3
Populations under particular pressure

             The eastern population that occurs in South Australia, Victoria, New South Wales and Tasmania has recorded significant decreases over the last 20 years (Garnett et al. 2011; Greenwell et al. 2021). The eastern population may be as low as 1,300–1,600 mature individuals. Conservation efforts should focus on the eastern population to facilitate an increasing population trend over the life of this Recovery Plan.

             3.1 Local conservation strategies

             Dunlop (2018) outlines a number of practical solutions for protecting colonies from human encroachment, predators and innovative ways to boost breeding success.
             One approach to improving Australian Fairy Tern breeding performance within local coastal populations is to encourage the terns to select secure or manageable nesting sites. This can be done using social facilitation techniques that involve the deployment of decoys (models of incubating terns) in configurations that mimic the early stages of colony formation and playbacks of colony noises (Dunlop 2018). The effectiveness of the decoy colonies can also be augmented with continuous playback of contact (flock) or advertising calls, although this may not be necessary in all situations.

             Decoy colonies have been used successfully on tern species that nest close together and do not retain nest sites between breeding attempts (e.g. Dunlop 1987). Social facilitation methods have been used effectively on Crested, Caspian, Sooty and Least Terns, and will probably be effective for Australian Fairy Terns (Dunlop 2018). The basic preconditions for attracting terns to a preferred location are an appropriate nesting habitat type, overflying terns in breeding condition and sufficient prey resources within the economic foraging range (Dunlop 2018).

   Preferred nesting sites for Australian Fairy Terns, whether natural or artificial,