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Pristis microdon
– Critically Endangered
Taxonomy
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Kingdom:
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ANIMALIA
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Phylum:
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CHORDATA
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Class:
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CHONDRICHTHYES
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Order:
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RAJIFORMES
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Family:
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PRISTIDAE
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Scientific Name:
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Pristis microdon
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Species Authority:
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Latham, 1794
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Common Name/s:
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| English | — | FRESHWATER SAWFISH, LARGETOOTH SAWFISH, LEICHHARDT'S SAWFISH, SMALLTOOTH SAWFISH |
| French | — | POISSON-SCIE |
| Spanish | — | PEJEPEINE, PEZ SIERRA |
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Taxonomic Notes:
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The genus Pristis is taxonomically chaotic with uncertainty regarding the true number of valid species. The practical difficulties associated with resolving these taxonomic issues are acute, since it is extremely difficult to obtain specimens or tissue samples from these increasingly rare species for taxonomic research. Family Pristidae contains one mono-specific genus (Anoxypristis) and one genus (Pristis) of four to six species, grouped by similar visual characteristics. The 'Pristis pristis complex'; (Pristis pristis, P. microdon and P. perotteti), has relatively broad-based, strongly tapered and massive saws, with fewer (under 22) large teeth. P. microdon may not be distinct from the largetooth sawfish P. perotteti, which occurs in the Americas and west Africa. Field research and collection of specimens from both groups for comparison will be needed to verify the uniqueness of these two species. Some of the members of these groups may be sub-species or geographically distinct populations rather than valid species, but because many populations have been extirpated their precise genetic identity may never be resolved (Compagno and Cook 1995a, 2005a,b).
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Assessment Information
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Red List Category & Criteria:
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CR A2abcd+3cd+4bcd ver 3.1 (2001)
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Year Assessed:
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2006
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Assessor/s:
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Compagno, L.J.V., Cook, S.F. & Fowler, S.L.
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Evaluator/s:
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van der Elst, R., Everett, B. & participants of the Shark Specialist Group Subequatorial Africa workshop (Shark Red List Authority)
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Justification:
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A large eurohaline Indo-Pacific species of sawfish that has mostly been reported in freshwaters of Southeast Asia and Australia, also in southeastern African rivers, but probably always has been more common in coastal waters where it is less noticeable. It is characterised by extreme and continued vulnerability to fisheries (evidenced by serious declines in virtually all known populations), compounded by habitat loss and degradation over most of its range. Remaining populations are now small, fragmented and Critically Endangered globally.
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History:
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| 1996 | - | Endangered as Pristis microdon (Southeast Asian subpopulation) (Baillie and Groombridge 1996) |
| 2000 | - | Endangered (Hilton-Taylor 2000) |
| 2000 | - | Critically Endangered (Hilton-Taylor 2000) |
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Geographic Range
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Range Description:
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A euryhaline species (except in Australia where it has only been recorded in freshwater) of the Indo-Pacific region. It has been recorded from southern Africa to Southeast Asia and the Indo-Australian Archipelago including Australia and the Philippines (Fowler 1941, Wallace 1967, Misra 1969, Paxton et al. 1989, Compagno et al. 1989, Last and Stevens 1994, Compagno and Cook 1995a).
Freshwater records of Pristis microdon include rivers of South Africa, in the Shire, Zambezi, Sabie, and Lundi Rivers of Mozambique and Zimbabwe; Ganges and Bramaputra Rivers of India; possibly from the Chaophraya at Nantaburi above Paknam in Thailand; Perak, and possibly the Trembeling and Linggi Rivers in mainland Malaysia; the Kinabatangan and other large rivers in Sabah, Borneo; Grand Lac in Cambodia (Kampuchea); at Lake Naujan, Mindoro Island in the Philippines; Indragiri River near Rengat, Sumatra and Bandjermassing, Borneo in Indonesia; the Fly river system, Sepik and Laloki Rivers, and Lake Murray in Papua-New Guinea; Gilbert, Mitchell, Daly, Victoria, Ord, Fitzroy, Lynd, Walsh, Palmer, and Alligator Rivers, and Teogangini Creek in Australia (Boulenger 1909, Annandale 1909, Fowler 1941, Whitley 1940 and 1945, Smith 1945, Boeseman 1956, Alfred 1962, Stead 1963, Jubb 1967, Munro 1967, Misra 1969, Grant 1972 and 1978, Roberts 1978, Taniuchi 1979, Kottelat 1985, Merrick and Schmida 1984, Taniuchi and Shimizu 1991, Taniuchi et al. 1991, Last and Stevens 1994, Compagno and Cook 1995a, Skelton 2001).
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Countries:
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Native:
Australia; Bangladesh; Cambodia; India; Indonesia (Kalimantan, Sumatera); Malaysia (Sabah); Mozambique; Myanmar; Papua New Guinea; Philippines; South Africa; Sri Lanka; Thailand
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FAO Marine Fishing Areas:
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Native:
Indian Ocean-eastern; Indian Ocean-western; Pacific-western central
Uncertain presence and origin:
Pacific-southwest
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Population
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Population:
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Populations are becoming increasingly rare and fragmented and all those known are severely threatened by target and bycatch fisheries and deterioration of habitats. Many populations have been extirpated or nearly extirpated from large areas of their former range, with no or only very few observations reported in most range states since the 1960s, although they were reportedly common in many inshore waters at the end of the 19th century and early 20th century.
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Population Trend:
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Habitat and Ecology
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Habitat and Ecology:
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A large (to 700 cm) euryhaline sawfish with 18 to 23 evenly-spaced rostral teeth starting near the rostral base and extending over the entire length of the saw on each side; the posterior margin of the slender rostral teeth is grooved. It has broad nostrils with large nasal flaps, dorsal fins are high and pointed with first dorsal well forward of the pelvic-fin origins and the caudal fin lower lobe is small but distinct (Last and Stevens 1994).
This species, like the largetooth sawfish of the Americas, occurs far up rivers and in freshwater lakes throughout its range. However, it no longer occurs in a number of freshwater habitats where it was formerly recorded. The species is seen and very occasionally caught seasonally along with the bull shark Carcharhinus leucas, in rivers in Sabah, North Borneo, and, in lower stretches of the rivers, with the green sawfish Pristis zijsron (Compagno and Cook 2005b).
The sawfishes are all ovoviviparous. The biology of this species is virtually unknown where it occurs, but, as with P. perotteti, it apparently breeds in fresh water. Size at maturity is unknown. Mature whole specimens are generally lacking in collections because of their size, but dried isolated rostra are generally well represented in collections although they often lack data (L. Compagno pers. obs).
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System:
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Freshwater; Marine
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List of Habitats:
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| 9.1 | Marine Neritic - Pelagic |
| 12.4 | Marine Intertidal - Mud Flats and Salt Flats |
| 13.4 | Marine Coastal/Supratidal - Coastal Brackish/Saline Lagoons/Marine Lakes |
| 17 | Other |
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Threats
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Threats:
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The principal threat to all sawfishes is fisheries, both targeted and bycatch, commercial and subsistence. Their morphology, particularly the long tooth-studded saw, makes them extraordinarily vulnerable to entanglement in any sort of net gear, including primitive fishing technology, and regardless of population size (which was probably always fairly small). When sawfish are taken in bycatch, they are often retained (particularly in areas where there is no legal protection) because of the very high value of their products (meat is high quality and fins and rostral saws extremely valuable in international trade). They are also targeted opportunistically for the same reasons. Very large specimens have also been the target of trophy angling, e.g., in the Kinabatangan River, Sabah (L. Compagno pers. obs).
According to the FAO online database, FIGIS, sawfish landings were recorded between 1962 and 2001, with a peak of 1759 t in 1978 worldwide, but most of these were outside the main Indo-Pacific range of this primarily freshwater species and some annual figures appear to be extrapolations from previous years. Reported landings have since declined steeply. Most reports suggest that numbers taken by fisheries from a great many localities have fallen noticeably since the 1960s, if not earlier.
There is increasing demand for live sawfish to put on display in public aquaria, with most specimens sourced from Australia. The mortality rates associated with securing live sawfishes for this use is unknown.
Major habitat impacts include river engineering (particularly dams), siltation from logging and agricultural activity upstream, and pollution from industries and mining operations. P. microdon has disappeared from many freshwater habitats (i.e., Chaophraya River, Thailand, for example, where it has not been reported in several decades (L. Compagno pers. obs). It was apparently wiped out along with other fishes in the Fly River system of Papua-New Guinea by recurrent, massive cyanide spills from heap-leach mining operations (Tyson Roberts, Bangkok personal communication 1996). Increased agricultural and industrial use of water in catchments reduces flow, closes river mouths and alters salinity, exacerbating the effects of climate change. This is currently very evident at St Lucia estuary in South Africa, which was once the major site for Pristis. Last and Stevens (1994) report that the species is highly vulnerable to gillnet fishing and that Australian populations may be threatened in streams by bycatch in poaching operations for barramundi Lates calcarifer.
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List of Threats:
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| 1.1.6 | Habitat Loss/Degradation - Agriculture - Marine aquaculture (ongoing) |
| 1.1.8 | Habitat Loss/Degradation - Agriculture - Other (ongoing) |
| 1.1.9 | Habitat Loss/Degradation - Agriculture - Unknown (ongoing) |
| 1.3.1 | Habitat Loss/Degradation - Extraction - Mining (ongoing) |
| 1.3.3 | Habitat Loss/Degradation - Extraction - Wood (ongoing) |
| 1.4.1 | Habitat Loss/Degradation - Infrastructure development - Industry (ongoing) |
| 1.4.2 | Habitat Loss/Degradation - Infrastructure development - Human settlement (ongoing) |
| 1.4.3 | Habitat Loss/Degradation - Infrastructure development - Tourism/recreation (ongoing) |
| 1.4.6 | Habitat Loss/Degradation - Infrastructure development - Dams (ongoing) |
| 3.1.1 | Harvesting (hunting/gathering) - Food - Subsistence use/local trade (ongoing) |
| 3.1.2 | Harvesting (hunting/gathering) - Food - Sub-national/national trade (ongoing) |
| 3.2.1 | Harvesting (hunting/gathering) - Medicine - Subsistence use/local trade (ongoing) |
| 3.5.2 | Harvesting (hunting/gathering) - Cultural/scientific/leisure activities - Sub-national/national trade (ongoing) |
| 4.1.1.1 | Accidental mortality - Bycatch - Fisheries-related - Hooking (past, present) |
| 4.1.1.2 | Accidental mortality - Bycatch - Fisheries-related - Netting (ongoing) |
| 4.1.1.3 | Accidental mortality - Bycatch - Fisheries-related - Entanglement (ongoing) |
| 6.3.2 | Pollution (affecting habitat and/or species) - Water pollution - Domestic (ongoing) |
| 6.3.3 | Pollution (affecting habitat and/or species) - Water pollution - Commercial/Industrial (ongoing) |
| 6.3.4 | Pollution (affecting habitat and/or species) - Water pollution - Other non-agricultural (ongoing) |
| 6.3.6 | Pollution (affecting habitat and/or species) - Water pollution - Oil slicks (ongoing) |
| 6.3.7 | Pollution (affecting habitat and/or species) - Water pollution - Sediment (ongoing) |
| 6.3.8 | Pollution (affecting habitat and/or species) - Water pollution - Sewage (ongoing) |
| 7.1 | Natural disasters - Drought (ongoing) |
| 9.1 | Intrinsic factors - Limited dispersal (ongoing) |
| 9.2 | Intrinsic factors - Poor recruitment/reproduction/regeneration (ongoing) |
| 9.5 | Intrinsic factors - Low densities (present, future) |
| 9.7 | Intrinsic factors - Slow growth rates (ongoing) |
| 9.9 | Intrinsic factors - Restricted range (ongoing) |
| 10.1 | Human disturbance - Recreation/tourism (ongoing) |
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Conservation Actions
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Conservation Actions:
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Indonesia enacted legislation to protect sawfishes (and five other freshwater fish species) in Lake Sentani, West Papua, following severe depletion of populations in a gill net fishery (Compagno and Cook 2005a).
South Africa has outlawed the capture of all sawfish species for many years; first protection at KwaZulu-Natal provincial level was in 1978, national as critical in 1997.
Australia’s Commonwealth Environment Protection and Biodiversity Conservation Act (EPBC) lists Pristis microdon as a Protected species and Vulnerable in Queensland.India’s Ministry of Environment and Forests has protected all species of sawfishes under the Wildlife Protection Act (WPA) 1972 since 2001.
In January 2006, eBay announced it would ban the sale of sawfish parts and products on their on-line auction site. This measure will require vigilant monitoring within eBay and with the help of outside experts.
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List of Conservation Actions:
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| 1.1.1 | Policy-based actions - Management plans - Development (in place, needed) |
| 1.1.2 | Policy-based actions - Management plans - Implementation (needed) |
| 1.2.1.1 | Policy-based actions - Legislation - Development - International level (needed) |
| 1.2.1.2 | Policy-based actions - Legislation - Development - National level (in place, needed) |
| 1.2.2.1 | Policy-based actions - Legislation - Implementation - International level (needed) |
| 1.2.2.2 | Policy-based actions - Legislation - Implementation - National level (needed) |
| 1.2.2.3 | Policy-based actions - Legislation - Implementation - Sub-national level (needed) |
| 2.1 | Communication and Education - Formal education (needed) |
| 2.2 | Communication and Education - Awareness (needed) |
| 3.1 | Research actions - Taxonomy (needed) |
| 3.2 | Research actions - Population numbers and range (needed) |
| 3.3 | Research actions - Biology and Ecology (needed) |
| 3.6 | Research actions - Uses and harvest levels (needed) |
| 3.8 | Research actions - Conservation measures (needed) |
| 3.9 | Research actions - Trends/Monitoring (needed) |
| 4.1 | Habitat and site-based actions - Maintenance/Conservation (needed) |
| 4.2 | Habitat and site-based actions - Restoration (needed) |
| 4.4.1 | Habitat and site-based actions - Protected areas - Identification of new protected areas (needed) |
| 4.4.2 | Habitat and site-based actions - Protected areas - Establishment (in place, needed) |
| 4.4.3 | Habitat and site-based actions - Protected areas - Management (in place, needed) |
| 4.4.4 | Habitat and site-based actions - Protected areas - Expansion (needed) |
| 5.3.1 | Species-based actions - Sustainable use - Harvest management (needed) |
| 5.3.2 | Species-based actions - Sustainable use - Trade management (needed) |
| 5.4 | Species-based actions - Recovery management (needed) |
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Bibliography
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Bibliography:
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Alfred, E.R. 1962. Sharks, rays and sawfishes in Malayan fresh waters. Malayan Nature Journal 16(4): 235 Annandale, N. 1909. Report on the fishes taken by the Bengal fisheries steamer "Golden Crown". Part 1: Batoidei. Memoirs of the Indian Museum 2(1): 1–60. Baillie, J. and Groombridge, B. (compilers and editors) 1996. 1996 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland. Beebe, W. and Tee-Van, J. 1941. Eastern Pacific expeditions of the New York Zoological Society. 25. Fishes from the tropical eastern Pacific. Part 2. Sharks. Zoologica 26: 93-122. Boeseman, M. 1956. Freshwater saw-fishes and sharks in Netherlands Guinea. Science 123: 222–223. Boulenger, G.A. 1909. Catalogue of the Freshwater Fishes of Africa. Vol 1. British Museum (Natural History), London, United Kingdom. Breder Jr., C.M. 1952. On the utility of the saw in the sawfish. Copeia 2: 90–91. Compagno, L.J.V. and Cook, S.F. 1995. The exploitation and conservation of freshwater elasmobranchs: status of taxa and prospects for the future. The biology of Freshwater elasmobranchs. The Journal of Aquariculture and Aquatic Science. 7: 62–90. Compagno, L.J.V. and Cook, S.F. 2005. Great-tooth or freshwater sawfish Pristis microdon. In: S.L. Fowler, M. Camhi, G.H. Burgess, G.M. Cailliet, S.V. Fordham, R.D. Cavanagh, C.A. Simpfendorfer, and J.A. Musick (eds) Sharks, rays and chimaeras: the status of the chondrichthyan fishes. IUCN SSC, Cambridge, UK and Gland, Switzerland. Compagno, L.J.V. and Cook, S.F. 2005. Order Pristiformes, sawfishes. In: S.L. Fowler, M. Camhi, G.H. Burgess, G.M. Cailliet, S.V. Fordham, R.D. Cavanagh, C.A. Simpfendorfer, and J.A. Musick (eds) Sharks, rays and chimaeras: the status of the chondrichthyan fishes. IUCN SSC, Cambridge, UK and Gland, Switzerland. Compagno, L.J.V., Ebert, D.A. and Smale, M.J. 1989. Guide to the sharks and rays of Southern Africa. Struik, Cape Town. 160 pp. Day, F. 1873. Report on the fresh water fish and fisheries of India and Burma. Office of the Superintendent of Government Printing, Calcutta. Fowler, H.W. 1941. The fishes of the groups Elasmobranchii, Holocephali, Isospondyli, and Ostariophysi obtained by United States Bureau of Fisheries Steamer Albatross in 1907 to 1910, chiefly in the Philippines Islands and adjacent seas. Bulletin of the United States National Museum (100) 13: 1-879. Fowler, S.L., Cavanagh, R.D., Camhi, M., Burgess, G.H., Cailliet, G.M., Fordham, S.V., Simpfendorfer, C.A. and Music, J.A. 2005. Sharks, Rays and Chimaeras: The Status of the Chondrichthyan Fishes. IUCN SSC Shark Specialist Group. IUCN, Gland, Switzerland and Cambridge, UK. Grant, E.M. 1991. Fishes of Australia. E.M. Grant Pty Ltd, Redcliffe, Queensland, Australia. Hilton-Taylor, C. (compiler). 2000. 2000 IUCN Red List of Threatened Species. IUCN, Gland, Switzerland and Cambridge, UK. Jubb, R.A. 1967. Freshwater fishes of southern Africa. A.A. Balkema, Cape Town & Amsterdam. Kottelat, M. 1985. Fresh-water fishes of Kampuchea. A provisory annotated check-list. Hydrobiologia. 121: 249–279. Last, P.R. and Stevens, J.D. 1994. Sharks and Rays of Australia. CSIRO, Australia. Misra, K.S. 1969. Elasmobranchii and Holocephali. In: M.L. Roonwal (ed.) The fauna of India and the adjacent countries. Pisces (second edition). Zoological Survey of India Series. Government of India Press, Faridabad. Munro, I.S.R. 1967. The fishes of New Guinea. Department of Agriculture, Stock and Fisheries, Port Moresby, New Guinea. Paxton, J.R., Hoese, D.F., Allen, G.R. and Hanley, J.E. 1989 Zoological Catalogue of Australia. Vol. 7. Pisces. Petromyzontidae to Carangidae. Australian Biological Resources Study, Australian Government Publishing Service, Canberra Roberts, T.R. 1978. An ichthyological survey of the Fly River in Papua New Guinea with descriptions of new species. Smithsonian Contributions to Zoology 281: 1–72. Shark Specialist Group. For more information, see the Specialist Group website. Skelton, P.H. 2001. A Complete Guide to the Freshwater Fishes of Southern Africa. Struik Publishers, Cape Town, South Africa. Smith, H.M. 1945. The fresh-water fishes of Siam, or Thailand. United States Government Printing Office, Washington D.C. Stead, D.G. 1963. Sharks and rays of Australian seas. Angus and Robertson, Sydney, Australia. Taniuchi, T. 1979. Freshwater elasmobranchs from Lake Naujan, Perak River, and Indragiri River, southeast Asia. Japanese Journal of Ichthyology 25(4): 273–277. Taniuchi, T., Khan, T.T., Tanaka, S. and Otake, T. 1991. Collection and measurement data and diagnostic characters of elasmobranchs collected from three rivers in Papua, New Guinea. Nature and Culture 3: 27–41. Van der Elst, R. 1981. A guide to the common sea fishes of Southern Africa. Capetown, C. Struik. Wallace, J.A. 1967. The batoid fishes of the east coast of southern Africa. Part I: Sawfishes and guitarfishes. South African Association for Marine Biological Research. Oceanographic Research Institute, Investigational Report 15.
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