Document ID: chunk:federal_register_of_legislation:F2022L00775:reg:18:p98
Version: federal_register_of_legislation:F2022L00775
Segment Type: reg
Provision Reference: reg 18 (pt 98/152)
Character Range: 310042–313143

for Seabirds 133
Species profiles

Sooty Tern (Onychoprion fuscatus)

  Life History and Distribution
  The Sooty Tern (Onychoprion fuscatus) is a medium-sized tropical tern, slightly larger than Bridled Tern and larger than the noddies (Anous spp.). The species has an extremely large range through most of the tropical oceans (del Hoyo et al. 1996). It breeds on flat, open, sparsely or heavily vegetated, oceanic or barrier islands of sand, coral or rock in productive tropical and subtropical offshore waters rich in plankton, fish and squid (del Hoyo et al. 1996; Surman and Wooller 2003). It is absent from cold current areas and generally avoids islands with terrestrial predators (del Hoyo et al. 1996). Outside of the breeding season, the species is highly oceanic, but generally avoids cold current areas (del Hoyo et al. 1996). Its diet consists predominantly of fish and squid (Surman and Wooller 2003), but it also occasionally takes crustaceans, insects and offal (del Hoyo et al. 1996). The species is reliant upon prey driven to the surface by predatory fish (e.g. tuna), especially when breeding (Higgins and Davies 1996).

  Population Estimates and Trends
The global population is estimated to number 21,000,000-22,000,000 individuals (Delany and Scott 2006). The overall population trend is uncertain, as some populations are decreasing, while others are increasing or have unknown trends (Delany and Scott 2006). Large populations occur in Western Australia (293,000–388,000 pairs; Burbidge et al. 1996), Queensland (King 1996) and the Coral Sea Marine Park. A 2019 survey of Ashmore Reef Marine Park found Sooty Terns to be the most abundant bird species at Ashmore with over 77,000 recorded (Cannell and Surman 2020).

  Conservation Concerns and Actions
Colonies have declined in line with observed increases in sea temperatures in Australia, in contrast to the fortunes of Bridled Tern, which have formed new colonies further south (Dunlop and Surman 2012). Variations in sea surface temperature have been shown to negatively influence the species' foraging success at breeding colonies, hence lowering reproductive success (Erwin and Congdon 2007). Previously, in some parts of its range, persistent large-scale egg-collecting has encouraged the species to move to suboptimal nesting sites, resulting in higher mortality and reduced reproductive success (van Halewyn and Norton 1984). Invasive species are threatening some populations.

  Recommended Management Actions
          Quantify the breeding population in Australia

          Regularly monitor breeding populations at index locations

          Determine non-breeding areas and migration routes

          Quantify and manage the potential impacts of human disturbance

          Control, or eradicate invasive species on breeding islands

      Implement best practice quarantine measures at breeding colonies to reduce the risk of any invasive species (re)establishing on islands

134 Wildlife Conservation Plan for Seabirds
Species profiles

 Little Tern (Sternula albifrons)

 Life History and