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Home , Cambridge Gulf, Carcharhiniformes, Northern river shark, River shark, Speartooth shark

This Conservation Advice was approved by the Delegate of the Minister on 11 April 2014

Approved Conservation Advice for Glyphis glyphis (speartooth )

(s266B of the Environment Protection and Biodiversity Conservation Act 1999)

This Conservation Advice has been developed based on the best available information at the time this Conservation Advice was approved; this includes existing and draft plans, records or management prescriptions for this .

Description

Glyphis glyphis (), family Carcharhinidae, also known as Bizant shark and , is a medium-sized whaler shark characterised by a short snout, broadly rounded in dorsoventral view, bluntly pointed in lateral view; tall second , height 67–76% of first dorsal-fin; 26-29 triangular, blade-like upper teeth and 27-29 tall narrow lower teeth. It has a slate greyish coloration dorsally and is abruptly white below, with tonal junction extending just below the and a total vertebrae count of 213–222 (Last & Stevens, 2009; Compagno et al., 2008). Based on limited data, speartooth are approximately 50-60 cm at birth and are believed to grow to over 2 m when mature (Stevens et al., 2005; Pillans et al., 2008).

Conservation Status

Speartooth sharks (Glyphis glyphis) are listed as critically endangered under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). The species is eligible for listing as critically endangered as it satisfies criterion 2 (geographic distribution), 3 (population size and decline in numbers or distribution) and 4 (population size) of the eligibility criteria (TSSC, 2001). The species was listed as critically endangered in 2001 based on its limited geographic distribution and the estimated total number of mature individuals being extremely low and likely to continue to decline (TSSC, 2001).

In the the species is listed as vulnerable under the Territory Parks and Wildlife Conservation Act 2000 and as a ‘no take’ species under the Fisheries Act 1988. In Queensland the species is listed as a protected ‘no take’ species under the Fisheries Act 1994 and Fisheries Regulations 2008. In Western the species is listed as a totally protected under the Fish Resources Management Act 1994. In New South Wales the species is listed as presumed extinct under the Fisheries Management Act 1994.

The species is also listed as endangered (status C2a(i)) on the IUCN Red List of Threatened Species (IUCN, 2013).

Cultural Significance

Fishing of elasmobranchs is a part of traditional fishing practices and historically makes up an important part of the diet of coastal indigenous communities. Indigenous Australians are allowed to take and eat speartooth sharks for personal, domestic or non-commercial communal needs.

Distribution and

Speartooth sharks are elasmobranchs capable of living in and moving between freshwater and . Juvenile and sub-adult speartooth sharks utilise large tropical river systems as their primary habitat (Stevens et al., 2005). Based on physiological and life history similarities with bull sharks ( leucas), it is assumed adult speartooth sharks may live outside of in the coastal marine environment (Stevens et al., 2005; Pillans et al., 2008). Speartooth sharks have been recorded in tidal rivers and with turbid waters, fine muddy substrates and temperatures ranging from 27 to 33°C (Pillans et al., 2009).

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Data on the short-term movement patterns of a small number of neonate and juvenile speartooth sharks in the Adelaide and Wenlock Rivers indicates that individuals have a tidally influenced movement pattern, moving up and downstream with the flood and ebb , and primarily swim well above the bottom (Pillans et al., 2008). Surveying shows that individuals repeatedly utilise small sections of the available habitat (Pillans et al., 2009).

Within Australia, speartooth sharks are known to occur, or have historically occurred, in four geographically distinct locations. These are: 1) Cambridge Gulf, ; 2) drainage, Northern Territory, including the Adelaide River, South, East and West and Murganella Creek; 3) Port Musgrave, Queensland, including the Wenlock and Ducie Rivers; and 4) the area of Eastern Cape York (Field et al., 2008, Pillans et al., 2009). However, it is likely that speartooth sharks are extirpated from several Queensland river systems in which they were previously found, with no confirmed records from Queensland’s east coast since 1983. Remaining populations are often isolated, raising concerns about their viability.

Outside of Australia, speartooth sharks are only known to occur in Papua New Guinea from Port Romilly and the Fly River (Compagno et al., 2008). The relationship between the Australian and global populations is poorly understood. It is currently unknown what percentage of the global population occurs in Australia.

There has been no genetic research into the population structure of speartooth sharks, which makes it difficult to determine if the identified populations mix and, if they do, the extent of their mixing. Additional data on speartooth shark distribution, and population genetic analyses, are needed to determine the degree of fragmentation and/or connectivity between populations.

Given the threatened status of this species, all river systems where speartooth sharks have been recorded are important. All populations are considered to be of high conservation value and hence the actions described below are designed to provide ongoing protection for speartooth sharks throughout their Australian ranges.

This species has been recorded in riverine and marine environments in three geographically distinct locations in northern Australia and is known to have occurred within most of the tropical IBRA Bioregions and Natural Resource Management Regions in the Van Dieman Gulf area of the Northern Territory and within the Cape York Peninsula IBRA Bioregion in Queensland.

The distribution of this species is not known to overlap with any EPBC Act-listed threatened ecological communities.

Threats

The main identified threats to speartooth sharks, are activities, , Indigenous fishing, illegal, unreported and unregulated fishing (IUU), and habitat degradation and modification (Department of the Environment, 2014).

Fisheries includes all non-target species caught while fishing. Speartooth sharks are known to be caught as bycatch in Australian fisheries, with the potential for interactions to occur in at least six fisheries operating in Australian waters. It is not an offence to catch this species while fishing but any captures need to be reported to the relevant state or territory authority or to the Commonwealth. However, logbook recordings of interactions with protected species often fail to identify sharks to the species level, and Glyphis glyphis is particularly difficult to distinguish from Glyphis garricki () in areas where both species co-occur. There is also evidence to suggest that interactions are often under- reported, with observer data from one fishery indicating that interactions with speartooth sharks may be significantly higher than the figures recorded in logbooks would suggest (DEEDI, 2010). Post release survivorship remains a largely unknown factor.

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The recreational catch of speartooth sharks is banned by legislation in Western Australia, Northern Territory and Queensland. Any sharks captured must be returned to the water unharmed and as quickly as possible. The impact of recreational fishing, accidental or intentional, is largely unknown. However, pressure on speartooth sharks may increase as recreational fishers increasingly access more remote parts of Northern Australia.

Native Title holders have legal rights to hunt and fish for personal, domestic or non- commercial communal needs. These rights allow for the harvest of speartooth sharks. Indigenous people are known to occasionally take Glyphis species during fishing activities but are not known to specifically target these species. The number of speartooth sharks caught by Indigenous fishers is currently unknown but likely to be low.

The primary IUU threat comes from foreign vessels illegally fishing in Australian waters for the shark fin trade. Such fishing has been documented (Field et al., 2009) but the magnitude of the threat is unknown. In 2005, it was estimated that the illegal foreign take of sharks in the was at least equivalent to the domestic legal catch (Pascoe et al., 2008), although these levels are thought to have since decreased significantly (Lack & Sant, 2008).

A wide range of habitat-based threats exist for speartooth sharks. These include: coastal development, removal of /sea grass and land clearing; barriers in rivers; water quality and sedimentation; interruptions to migration pathways; water extraction; and, destruction of benthic habitat through bottom trawling. The impacts of these threats are largely unknown and likely to be localised. It is expected that the impacts of habitat degradation will be greater on juveniles because they tend to inhabit , estuarine and inshore more than adults. Impacts on natural river flow are of particular concern (DSEWPaC, 2012). Dams and barrages across rivers can impede migration (Thorburn, et al. 2007) and significantly affect natural flow regimes.

Potential threats to speartooth sharks include marine debris and the collection of for display in public aquaria.

Marine debris includes: land-sourced plastic garbage; derelict fishing gear from recreational and commercial fishing activities; and ship-sourced, solid non-biodegradable floating materials disposed of or abandoned in marine, coastal and riverine environments (DEWHA, 2009). The likelihood of interaction between marine debris and speartooth sharks in northern Australia is largely unknown. However, other small coastal sharks, of the same family have been found with plastic debris collars (Sazima et al., 2002) and recorded in ghost nets.

There are currently only a very small number of speartooth sharks held in Australian aquariums. However, it is possible to obtain permits for the collection of speartooth sharks for display in aquaria in some Australian states and territories and the effect of removing even a few individuals from a sub-population is largely unknown.

Research Priorities

Research priorities that would inform future priority actions include:

• Investigate the magnitude of the impacts of fisheries bycatch, recreational fishing, indigenous fishing and IUU fishing on speartooth sharks. • Investigate post-release survivorship and the effects of capture and release on the health of speartooth sharks. • Determine precisely how speartooth sharks respond to the variety of habitat-based threats that impact upon them and develop tools to predict the response of this species to changes in environmental conditions. • Identify important habitats for all life stages of speartooth sharks, including connectivity between regions and, where possible, produce habitat maps detailing pupping, nursery, feeding and aggregation areas in Australia.

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• Identify risks to important speartooth shark habitats and identify measures needed to reduce those risks. • Design and implement a cost-effective monitoring program, which includes the collection of samples for use in population genetics analysis, to improve knowledge of the life history, distribution, population structure and dynamics, and mortality parameters of speartooth sharks. • Investigate the extent to which interactions with marine debris, including ghost nets, fishing gear and plastics, are impacting upon the health and survival rates of speartooth sharks. • Refine and implement techniques (genetic and morphological) to identify speartooth shark products, including consideration of the use of DNA barcoding methods, as described by Holmes et al., 2009. • Investigate and quantify the extent of trade in speartooth shark products.

Priority Actions

The following priority recovery and threat abatement actions can be done to support the recovery of speartooth sharks across their range:

Commercial and Recreational Fishing • Promote cooperation and understanding between agencies and commercial and recreational fishers to improve recovery efforts for speartooth sharks. • Review and improve the ability of commercial fishery monitoring programs to provide accurate (validated) data on the extent of fishery interactions with speartooth sharks. • Encourage and educate recreational fishers to identify speartooth sharks to species level and report any interactions. • Consider new management arrangements to reduce commercial bycatch rates and ensure recommended actions are adopted in commercial fisheries. • Enhance the capabilities of enforcement and compliance for recreational and commercial fishery interactions with speartooth sharks. Indigenous Fishing • In collaboration with Indigenous communities develop and implement a community level program to promote speartooth shark conservation and enhance cooperation and understanding between agencies and Indigenous communities. Illegal, Unregulated and Unreported Fishing • Enhance the enforcement capabilities of agencies targeting IUU fishing of speartooth sharks. Habitat Loss, Disturbance and Modification • Implement measures to reduce adverse impacts of habitat degradation and/or modification. Marine Debris • Partner with marine debris organisations to support initiatives that reduce marine debris likely to impact on speartooth sharks. Collection for Aquaria • Partner with state governments and the aquaria industry to set strict requirements for take from the wild, including continuation of a moratorium on collection of speartooth sharks until the full extent of risks to local populations is better understood. • Develop and contribute to a conservation-oriented education program in those public aquaria with captive speartooth sharks.

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Conservation Information • Develop a portal for the synthesis of information on speartooth sharks to ensure that decision-makers and resource managers have the best and most up-to-date information available. • Disseminate outcomes of research projects on speartooth sharks. • Undertake coordinated community education programs, with priority given to those communities where greatest conservation outcomes are likely to be achieved.

This list does not necessarily encompass all actions that may be of benefit to speartooth sharks, but highlights those that are considered to be of highest priority at the time of preparing the Approved Conservation Advice.

Existing Plans/Management Prescriptions that are Relevant to the Species

Key management documentation available for this species includes:

• National Plan of Action for the Conservation and Management of Sharks 2012 (DAFF, 2012) • Draft Recovery Plan for and River Sharks (Department of the Environment, 2014) • The Commonwealth Threat Abatement Plan for the Impact of Marine Debris on Marine Life (DEWHA, 2009) • Draft Management Plan 2007-2014 (Department of the Environment, 2013)

These prescriptions were current at the time of publishing; please refer to the relevant agency’s website for any updated versions.

References

Compagno LJV, White WT and Last PR (2008). Glyphis garricki sp. nov., a new species of river shark (: Carcharhinidae) from northern Australia and Papua New Guinea, with a redescription of Glyphis glyphis (Müller and Henle, 1839). In: Last PR, White WT and Pogonoski JJ (eds). Descriptions of New Australian Chondrichthyans (pp. 203–225). Canberra: CSIRO.

Department of Agriculture, Fisheries and Forestry (DAFF) (2012). National Plan of Action for the Conservation and Management of Sharks 2012 (Shark-plan 2). Canberra: Department of Agriculture, Fisheries and Forestry. Available on the Internet at: http://www.daff.gov.au/fisheries/environment/sharks/sharkplan2

Department of Employment, Economic Development and Innovation (DEEDI) (2010). Annual status report 2010 Gulf of Carpentaria Inshore Fin Fish Fishery. Queensland: Department of Employment, Economic Development and Innovation.

Department of the Environment (2013). Draft Kakadu National Park Management Plan 2007- 2014. Canberra: Department of the Environment. Available on the Internet at: http://www.environment.gov.au/system/files/resources/39d19c4b-90db-438b-b1e9- 6b6195988d69/files/draft-issues-paper-sawfish-and-river-sharks.pdf.

Department of the Environment (2014). Draft Recovery Plan for Sawfish and River Sharks. Canberra: Department of the Environment. Available on the Internet at: http://www.environment.gov.au/system/files/resources/39d19c4b-90db-438b-b1e9- 6b6195988d69/files/draft-recovery-plan-sawfish-and-river-sharks.pdf.

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Department of the Environment, Water, Heritage and the Arts (DEWHA) (2009). Threat Abatement Plan for the Impacts of Marine Debris on Vertebrate Marine Life. Canberra: Department of Environment, Water, Heritage and the Arts. Available on the internet at: www.environment.gov.au/biodiversity/threatened/publications/tap/marine-debris.html

Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC) (2012). Marine bioregional plan for the North Marine Region. Canberra: Department of Sustainability, Environment, Water, Population and Communities. Available on the internet at: http://www.environment.gov.au/coasts/marineplans/north/pubs/north-marine- plan.pdf

Field IC, Charters R, Buckworth RC, Meekan MG and Bradshaw CJA (2008). Distribution and abundance of Glyphis and in northern Australia and their potential interactions with commercial fisheries. Report to Australian Government, Department of the Environment, Water, Heritage and the Arts. Charles Darwin University: Darwin, Australia.

Field IC, Meekan MG, Buckworth RC and Bradshaw CJA (2009). Protein mining the world’s oceans: Australasia as an example of illegal expansion-and-displacement fishing. Fish and Fisheries 10: 323-328.

Holmes BH, Steinke D and Ward RD (2009). Identification of shark and ray fins using DNA barcoding. Fisheries Research, 95: 280-288.

International Union for the Conservation of Nature Shark Specialist Group (IUCN SSG) (2013). Glyphis glyphis. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.1. Available on the internet at: www.iucnredlist.org

Lack M and Sant G (2008). Illegal, unreported and unregulated shark catch: a review of current knowledge and action. Australian Government Department of the Environment, Water, Heritage and the Arts, and TRAFFIC, Canberra.

Last P and Stevens J (2009). Sharks and Rays of Australia. Second Edition. Commonwealth Scientific and Industrial Research Organisation (CSIRO).

Pascoe S, Okey TA and Griffiths S (2008). Economic and ecosystem impacts of illegal, unregulated and unreported (IUU) fishing in Northern Australia. Australian Journal of Agricultural and Resource Economics 36: 433-452.

Pillans RD, Stevens JD, Peverell S and Edgar S (2008). Spatial distribution and habitat utilisation of the speartooth shark Glyphis glyphis in relation to fishing in Northern Australia. Final report to Department of the Environment, Water, Heritage and the Arts. May 2008.

Pillans RD, Stevens JD, Kyne PM and Salini J (2009). Observations on the distribution, biology, short-term movements and habitat requirements of river sharks Glyphis spp. in northern Australia. Research, 10: 321–332.

Sazima I, Gadig OBF, Namora RC and Motta FS (2002). Plastic debris collars on juvenile carcharhinid sharks ( lalandii) in southwest Atlantic. Marine Pollution Bulletin, 44: 1147–1149.

Stevens JD, Pillans RD and Salini JP (2005). Conservation assessment of Glyphis glyphis (speartooth shark), Glyphis garricki (northern river shark), Pristis microdon (freshwater sawfish) and Pristis zijsron (green sawfish). Report to Department of Environment and Heritage, Canberra, Australia.

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Thorburn DC, Morgan DL, Rowland AJ and HS (2007). Freshwater sawfish Pristis microdon (: Pristidae) in the Kimberley region of Western Australia. Zootaxa, 1471: 27-41.

Threatened Species Scientific Committee (TSSC) (2001) Glyphis sp. A (Speartooth Shark). Department of Sustainability, Environment, Water, Population and Communities, Canberra. Available on the Internet at: http://www.environment.gov.au/biodiversity/threatened/species/speartooth- shark.html

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