Endangered, threatened and protected1 (ETP) species in WA are protected by various international agreements and national and state legislation. International agreements include:
• Convention on the Conservation of Migratory Species of Wild Animals 1979 (Bonn Convention);
• The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES);
• The Agreement between the Government of Australia and the Government of Japan for the Protection of Migratory Birds in Danger of Extinction and their Environment 1974 (JAMBA)2;
• The Agreement between the Government of Australia and the Government of the People’s Republic of China for the Protection of Migratory Birds and their Environment 1986 (CAMBA)2;
• The Agreement between the Government of Australia and the Government of the Republic of Korea on the Protection of Migratory Birds 2007 (ROKAMBA)2; and
• Any other international agreement, or instrument made under other international agreements approved by the Environment Minister.
Primary pieces of national and Western Australian legislation include the Commonwealth Environment Protection and Biodiversity Act 1999 (EPBC Act), the Western Australian Wildlife Conservation Act 1950 (WC Act), and the Fisheries Resource Management Act 1994 (FRMA).
A number of ETP species can be found within Shark Bay, including cetaceans (whales, dolphins and porpoises), marine turtles (Families Cheloniidae and Dermochelyidae), sea snakes (Families Hydrophiidae and Laticuadidae), elasmobranchs (sharks and rays), seahorses and pipefish (Families Syngnathidae and Solenostomidae), seabirds and migratory shorebirds (see Appendix G for a comprehensive species list including CITES listing).
1Note that being on a protected species list does not automatically indicate that a species is either threatened or endangered.
Marine Mammals
Shark Bay supports a variety of marine mammals including dugongs, whales and dolphins, with all of these species protected in Australia under the EPBC Act. The Bay supports one of the largest populations of dugongs in the world (approx. 10 000 – 12 000 individuals; DEC 2010b). These dugongs move seasonally within the Bay to stay within optimal water temperatures (Anderson 1986). Large numbers of dugongs and their young can be found on the Faure Sill and Wooramel Seagrass Bank and between Faure Island and Gladstone Bay during summer, while during winter they use the deeper water areas north of Peron Peninsula (Preen et al. 1997).
Cetaceans found within the Bay include southern right whales, Bryde’s whales and Indo- Pacific and common bottlenose dolphins. Shark Bay is also an important resting area for female humpback whales and their young calves as they migrate south along the WA coast to feeding grounds in the Antarctic (Jenner & Jenner 2000). Whaling and habitat degradation have been identified as the key threats to whales, and recovery plans for these species have been developed which establish objectives and actions to ensure the ongoing recovery of these species. The most recent recovery plans for these species are available at:
http://www.environment.gov.au/topics/marine/marine-species/whales-dolphins-and- porpoises/legislation.
Marine Turtles
Green turtles (Chelonia mydas) are the dominant marine turtle species in Shark Bay.
Carnivorous when young, they become mainly herbivorous on algae and seagrass as adults.
Loggerhead turtles (Caretta caretta) are less common in Shark Bay, but the Bay is believed to provide one of the most important breeding sites for this species in the state; approximately 70 % of loggerhead turtles in WA lay their eggs at Turtle Bay on the northern end of Dirk Hartog Island, Shelter Bay on the southern shores of the Southern Passage and the beaches of Dorre Island (Department of Envrionment 2003; DEC 2010a). Isolated individuals of hawksbill (Eretmochelys imbricata) and leatherback (Dermochelys coraicea) turtles have also been recorded in the Bay (CALM 1996). Marine turtles in Australia are protected under the EPBC Act. Threats to marine turtles have been identified as fisheries bycatch, customary harvesting, marine debris, shark control activities, boat strike, pearl farming and other aquaculture and defence activities. A recovery plan for these species has been developed by Commonwealth government and establishes objectives and actions to ensure their ongoing recovery. The most recent recovery plan for these species is available at:
http://www.environment.gov.au/resource/recovery-plan-marine-turtles-australia.
Sea Snakes
Shark Bay also supports a variety of sea snakes, with seven of the 22 known WA species recorded in Shark Bay (Storr et al. 2002). All seven species are tropical, with Shark Bay being the southernmost limit of their distribution (Storr & Harold 1990). Two species, the bar-bellied sea snake (Hydrophis elegans) and the olive-headed sea snake (Disteria major),
endemic to Shark Bay, where it is also very common. Occasionally, individuals of the golden sea snake (A. laevis), the spotted sea snake (H. ocellatus), the southern mud snake (Ephalophis greyae) and the yellow-bellied sea snake (Pelamis platura) can also be found in Shark Bay (Storr et al. 2002). Sea snakes are slow growing and have few offspring. As air breathers, they must come to the surface to breathe; however, they can spend from 30 minutes to two hours diving between breaths (Heatwole 1999). Consequently, many may survive being captured by trawl nets when trawl shots are short, i.e. less than 2 hours (Milton et al. 2009).
A study of sea snake survival following capture in trawlers in the Gulf of Carpentaria (Northern Territory) indicated that greater than 60 % of sea snakes survived capture in trawl nets (Wassenberg et al. 1994). It is likely that sea snakes captured in the SBPMF have a similar level of survival due to the short trawl times (50 – 180 mins) in the fishery.
Seahorses and Pipefish
Protected fish found within the bay include various sea horses and pipefish and sharks and rays, which are mainly found in the deeper waters (>10 m) of oceanic salinity (Kangas and Thomson 2004; Preen et al. 1997). Various species of syngnathids are found within the Bay, along seagrass beds and detached algal communities (Kangas et al. 2006). Some syngnathid populations may be particularly susceptible to pressures because their biology is characterised by relatively low population densities, lengthy parental care combined with small brood size limiting their reproductive rate, strict monogamy, sparse distribution, generally low rates of adult mortality, strong association with preferred habitat, and low mobility and small home ranges (Foster & Vincent 2004; Vincent 1996). However, although all members of the Syngnathidae and Solenostomidae families are listed marine species under the EPBC Act no species is currently listed as threatened. In shallower waters, pipefish and seahorses are a dominant group of fish and are important predators of benthic organisms such as mysids in the zooplankton and small amphipods. (e.g. Kendrick & Hyndes 2005; Martin- Smith 2008).
Sharks and Rays
At least 28 species of shark and six ray species occur in Shark Bay.
Seabirds
Shark Bay is also an important area for seabirds. Surveys by DPaW staff have recorded 14 species breeding in Shark Bay and another 50 species occurring in the Bay (CALM 1996).
Thirty-five of these species are listed in JAMBA, CAMBA and / or ROKAMBA. Shark Bay is internationally important for two species of shorebirds, the banded stilt and the eastern curlew, and is nationally important for five species of shorebirds: the wood sandpiper, the greenshank, the grey plover, the banded stilt and the eastern curlew (Watkins 1993). Areas in Shark Bay that are particularly important for seabirds and shorebirds include Faure Island, the eastern side of Dirk Hartog Island, Pelican Island and the spit on Salutation Island. Faure and
Pelican Islands and flats around them may constitute the most important area for migratory shorebirds in the Bay (Jaensch & Vervest 1990).