Largetooth Sawfish (Freshwater Sawfish), Pristis pristis (Linnaeus 1758)
A Freshwater Sawfish, Pristis pristis, in the Daly River, Northern Territory. Source: Richard Pillans. License: All rights reserved
The largest freshwater fish in Australia, found in marine, estuarine and freshwater habitats in northern Australia - up to 400 kilometres inland. The species has previously been referred to as Pristis microdon. The species is protected throughout Australia.
Identifying features: Gill openings on the underside; rostrum with a relatively broad base; rostral teeth evenly-spaced, extnding almost to rostral base; origin of first dorsal fin well before origin pelvic fins; lower lobe of caudal fin small, distinct, less than half length of upper lobe; yellowish to dark-brown above, underside white; outer fin margins yellowish-brown.
Video of the rescue of Freshwater Sawfish (aka Largetooth Sawfish) - Traditional Owners help scientists rescue critically endangered sawfish from a drying waterhole in the Daly River catchment, Northern Territory.
Video of Cairns Marine collecting juvenile Largetooth Sawfish in the Gulf of Carpentaria for conservation and display in public aquaria.
Largetooth Sawfish (Freshwater Sawfish), Pristis pristis (Linnaeus 1758)
More Info
|
Distribution |
Historically widespread in marine, estuarine and freshwater waters of the Eastern Atlantic, Western Atlantic, Eastern Pacific and Indo-West Pacific - with 4 genetically distinct populations. The Freshwater Sawfish is now extinct or severely depleted in numbers in much of its former range. In Australia, the species is known from 80 Mile Beach in Western Australia to Princess Charlotte Bay on the east coast of Queensland, with a single anomalous catch from Cape Naturaliste in southwestern Western Australia in 2007 (Phillips 2012). In the Fitzroy River system of northern Western Australia, the species has been recorded more than 400 km from the sea. The Freshwater Sawfish is a euryhaline species, able to move through salinity gradients. It inhabits inshore coastal waters, estuaries, river mouths lagoons, and large rivers. Thorburn et al. (2004) suggest that the Freshwater Sawfish is better described as a ‘marine opportunist’, and not as a ‘freshwater’ species. Juveniles occur in freshwaters, and upon maturation individuals may move out of rivers, or alternatively attain maturity outside rivers. |
|
Features |
Body elongate shark-like; snout highly modified into a flattened blade-like structure with 18-23 pairs of enlarged lateral tooth-like denticles (rostral teeth); rostral teeth slender with a groove along their posterior margins; teeth start near rostral base and are evenly spaced; rostrum broad, not tapering distally; five gill slits situated ventrally on the head; nostrils broad with large nasal flaps; barbels are absent; numerous very small, rounded-oval teeth in pavement pattern forming bands along jaws. Covered by small tooth-like dermal denticles. Two tall, pointed dorsal fins, first originating well forward of pelvic fin origin; pelvic fin origin closer to level of first dorsal fin insertion than to its origin; pectoral fins distinctly detached from head with broad bases, broadly triangular; caudal fin with distinct lower lobe, posterior margin of caudal fin concave. |
|
Size |
To a maximum total length (TL) of 700 cm, usually to 250 cm TL. Pups are born at 70-90 cm TL. |
|
Colour |
Yellowish to greyish, brown or olive above, white on the underside; outer fin margins yellowish brown. |
|
Feeding |
The top and underside of the saw-like snout or rostrum is covered in thousands of electrosensory ampullae of Lorenzini and several major branches of the motion sensory lateral line. These electroreceptors enable the sawfish to detect the weak electric fields of prey such as as molluscs, crustaceans and slow-moving fishes living on the bottom and in the water column. Once prey is detected, the sawfish sweeps its rostrum sideways to stun its prey. Sawfish - pups and small juveniles - are preyed upon by Bull Sharks (Carcharhinus leucas), estuarine crocodiles and the Australian freshwater crocodile. |
|
Biology |
Sawfish are aplacental viviparous (ovoviviparous) meaning that the eggs hatch within the body of the female who gives birth to 1-12 young in estuaries. Pups migrate upstream and spend their first 4-5 years in freshwater river systems - as far as 400 kms upstream in the Fitzroy River, Western Australia. When approaching maturity, subadults migrate back downstream to coastal waters, and mature at about 7 years of age. Individuals may live to about 40 years of age. |
|
Fisheries |
Although protected and not targeted commercially throughout Australia, Freshwater Sawfish are taken as incidental bycatch in gillnet and trawl fisheries in northern Australian. |
|
Conservation |
IUCN Red List of Threatened Species: Critically Endangered CITES Listed: Appendix I EPBC Act Australia: Vulnerable Northern Territory: Vulnerable Western Australia: Near Threatened Protected throughout Australia. The species has suffered populations declines throughout its range worldwide, and is locally extinct in some areas.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. |
|
Remarks |
Faria et al. (2013) demonstrated that there was little or no morphological or genetic differences between Pristis pristis, P. perotetti and P. microdon. As Pristis pristis is the oldest name, it is the accepted name for the Largetooth Sawfish. |
|
Species Citation |
Squalus pristis Linnaeus, 1758, Systema Naturae Tom.1 X: 235. Type locality: Mediterranean Sea, Indian Ocean & western Atlantic. |
|
Author |
Gomon, M.F. & Bray, D.J. 2019 |
|
Resources |
Largetooth Sawfish (Freshwater Sawfish), Pristis pristis (Linnaeus 1758)
References
Allen, G.R. 1982. Inland Fishes of Western Australia. Perth : Western Australian Museum 86 pp. 6 figs 20 pls. (as Pristis microdon)
Allen, G.R. 1997. Marine Fishes of Tropical Australia and South-east Asia. Perth : Western Australian Museum 292 pp. 106 pls. (as Pristis microdon)
Allen, G.R., Midgley, S.H. & Allen, M. 2002. Field Guide to the Freshwater Fishes of Australia. Perth : Western Australian Museum 394 pp. (as Pristis microdon)
Bradney, D.R., Davidson, A., Evans, S.P., Wueringer, B.E., Morgan, D.L. and Clausen, P.D. (2017) Sawfishes stealth revealed using computational fluid dynamics. Journal of Fish Biology 90(4): 1584-1596. http://dx.doi.org/10.1111/jfb.13255 Abstract
Compagno, L.J.V. & Last, P.R. 1999. Families Pristidae, Rhinidae, Rhinobatidae, Platyrhinidae. pp. 1410-1432 in Carpenter, K.E. & Niem, V.H. (eds). The Living Marine Resources of the Western Central Pacific. FAO Species Identification Guide for Fisheries Purposes. Rome : FAO Vol. 3 pp. 1397-2068. (as Pristis microdon)
Daley, R.K., Stevens, J.D., Last, P.R. & Yearsley, G.K. 2002. Field Guide to Australian Sharks & Rays. Hobart : CSIRO Marine Research 84 pp. (as Pristis microdon)
Dulvy, N.K., Davidson, L.N.K., Kyne, P.M., Simpfendorfer, C.A., Harrison, L.R., Carlson, J.K. & Fordham, S.V. 2016. Ghosts of the coast: global extinction risk and conservation of sawfishes. Aquatic Conservation: Marine and Freshwater Ecosystems 26: 134-153. DOI: 10.1002/aqc.2525 Open access
Faria, V. 2007. Taxonomic review, phylogeny, and geographical population structure of the sawfishes (Chondrichthyes, Pristiformes). PhD Dissertation, Iowa State University, USA
Faria, V.V., McDavitt, M.T. Charvet, P., Wiley, T.R., Simpfendorfer, C.A. & Naylor, G.J.P. 2012. Species delineation and global population structure of critically endangered sawfishes (Pristidae). Zoological Journal of the Linnean Society 167: 136-164 DOI: 10.1111/j.1096-3642.2012.00872x
Feutry, P., Kyne, P.M., Pillans, R.D., Chen, X., Marthick, J.R., Morgan, D.L. & Grewe, P.M. 2015. Whole mitogenome sequencing refines population structure of the Critically Endangered sawfish Pristis pristis. Marine Ecology Progress Series 533: 237–244. DOI: https://doi.org/10.3354/meps11354 Open access
Gleiss, A.C., Morgan, D.L., Whitty, J.M., Keleher, J.J., Fossette, S. & Hayes, G.C. 2017. Are vertical migrations driven by circadian behaviour? Decoupling of activity and depth use in a large riverine elasmobranch, the freshwater sawfish (Pristis pristis). Hydrobiologia 787: 181-191. https://doi.org/10.1007/s10750-016-2957-6 Abstract
Harrison, L.R. & Dulvy, N.K. (eds). 2014. Sawfish: A Global Strategy for Conservation. IUCN Species Survival Commission’s Shark Specialist Group, Vancouver, Canada, 116 pp.
Kyne, P.M., Carlson, J. & Smith, K. 2013. Pristis pristis (errata version published in 2019). The IUCN Red List of Threatened Species 2013: e.T18584848A141788242. http://dx.doi.org/10.2305/IUCN.UK.2013-1.RLTS.T18584848A141788242.en. Downloaded on 10 December 2019.
Lake, J.S. 1978. Australian Freshwater Fishes. Melbourne : Thomas Nelson 160 pp. 140 figs.
Last, P.R. & Stevens, J.D. 1994. Sharks and Rays of Australia. Canberra : CSIRO Australia 513 pp. 84 pls. (as Pristis microdon)
Last, P.R. & Stevens, J.D. 2009. Sharks and Rays of Australia. Collingwood : CSIRO Publishing Australia 2, 550 pp. (as Pristis microdon)
Last, P.R., White, W.T. & Naylor, G.J.P. 2016. 8. Sawfishes. Family Pristidae, pp. 58-64. In: Last, P.R., White, W.T., Carvalho, M.R. de, Séret, B., Stehmann, M.F.W. & Naylor, G.J.P. (eds.) Rays of the World. Clayton South, Victoria : CSIRO Publishing 790 pp.
Latham, J. 1794. An essay on the various species of sawfish. Transactions of the Linnean Society of London 2(25): 273-282 pls 26-27 (as Pristis microdon)
Lear, K.O., Gleiss, A.C., Whitty, J.M. et al. 2019. Recruitment of a critically endangered sawfish into a riverine nursery depends on natural flow regimes. Scientific Reports 9(17071) https://doi.org/10.1038/s41598-019-53511-9, open access
Linnaeus, C. 1758. Systema Naturae per Regna tria Naturae, secundem Classes, Ordines, Genera, Species, cum Characteribus, Differentis, Synonymis, Locis. Tom.1 Editio decima, reformata. Holmiae : Laurentii Salvii 824 pp.
Merrick, J.R. & Schmida, G.E. 1984. Australian Freshwater Fishes Biology and Management. Sydney : J.R. Merrick 409 pp. figs 280 col. figs.
Morgan, D.L., Allen, M.G., Bedford, P., & Horstman, M. 2004. Fish fauna of the Fitzroy River in the Kimberley region of Western Australia – including the Bunuba, Gooniyandi, Ngarinyin, Nyikina and Walmajarri Aboriginal names. Records of the Western Australian Museum 22: 147-161.
Morgan, D.L., Somaweera, R., Gleiss, A.C., Beatty, S.J. & Whitty, J.M. 2017. An upstream migration fought with danger: freshwater sawfish fending off sharks and crocodiles. Ecology 98: 1465–1467. doi:10.1002/ecy.1737 Open access
Morgan, D.L., Whitty, J.M., Phillips, N.M., Thorburn, D.C., Chaplin, J.A. & McAuley, R. 2011. North-western Australia as a hotspot for endangered elasmobranchs with particular reference to sawfishes and the Northern River Shark. Journal of the Royal Society of Western Australia 94: 345-358.
Peverell, S.C. 2008. Sawfish (Pristidae) of the Gulf of Carpentaria, Queensland, Australia. School of Marine Biology, James Cook University.
Phillips, N.M. 2012. Conservation genetics of Pristis sawfishes in Australian waters. PhD thesis. Murdoch University.
Phillips, N., Chaplin, J., Morgan, D. & Peverell, S. 2009. Extraction and amplification of DNA from the dried rostra of sawfishes (Pristidae) for applications in conservation genetics. Pacific Conservation Biology 15: 128–134.
Phillips, N.M., Chaplin, J.A., Morgan, D.L. & Peverell, S.C. 2011. Population genetic structure and genetic diversity of three critically endangered Pristis sawfishes in Australian waters. Marine Biology 158: 903-915.
Phillips, N.M., Chaplin, J.A., Peverell, S.C. & Morgan, D.L. 2016. Contrasting population structures of three Pristis sawfishes with different patterns of habitat use. Marine and Freshwater Research 68: 452-460. https://doi.org/10.1071/MF15427 Abstract
Phillips NM, Fearing A, Morgan DL (2017) Genetic bottlenecks in Pristis sawfishes in northern Australian waters. Endangered Species Research 32:363-372. https://doi.org/10.3354/esr00815 Open access
Salini, J., McAuley, R., Blaber, S., Buckworth, R., Chidlow, J., Gribble, N., Ovenden, J., Peverell, S., Pillans, R., Stevens, J., Stobutzki, I., Tarca, C. & Walker, T. 2007. Northern Australian sharks and rays: the sustainability of target and bycatch species, phase 2. Fisheries Research and Development Corporation Report 2002/064, CSIRO, Australia.
Stevens, J.D., Pillans, R.D. & Salini, J. 2005. Conservation assessment of Glyphis sp. A (speartooth shark), Glyphis sp. C (northern river shark), Pristis microdon (freshwater sawfish) and Pristis zijsron (green sawfish). Final Report to the Department of the Environment and Heritage.
Thorburn, D.C., Morgan, D.L., Rowland, A.J. & Gill, H.S. 2007. Freshwater sawfish Pristis microdon Latham, 1794 (Chondrichthys: Pristidae) in the Kimberley region of Western Australia. Zootaxa 1471: 27-41. (as Pristis microdon)
Thorburn, D.C., Peverell, S., Stevens, J.D., Last, P.R. & Rowland, A.J. 2003. Status of freshwater and estuarine elasmobranchs in northern Australia. Final report to Natural Heritage Trust.
Whitley, G.P. 1945. Leichhardt's sawfish. The Australian Zoologist 11(1): 43-45 fig. 1 (as Pristiopsis leichhardti)
Whitty JM, Keleher J, Ebner BC, Gleiss AC, Simpfendorfer CA, Morgan DL (2017) Habitat use of a Critically Endangered elasmobranch, the largetooth sawfish Pristis pristis, in an intermittently flowing riverine nursery. Endangered Species Research 34: 211-227. https://doi.org/10.3354/esr00837 Open access
Whitty, J.M., Morgan, D.L., Peverell, S.C., Thorburn, D.C. & Beatty, S.J. 2009. Ontogenetic depth partitioning by juvenile freshwater sawfish (Pristis microdon: Pristidae) in a riverine environment. Marine and Freshwater Research 60: 306–316. https://doi.org/10.1071/MF08169 (as Pristis microdon)
Whitty, J.M., Phillips, N.M., Morgan, D.L., Chaplin, J.A., Thorburn, D.C. & Peverell, S.C. 2008. Habitat associations of Freshwater Sawfish (Pristis microdon) and Northern River Shark (Glyphis sp. C): including genetic analysis of P. microdon across northern Australia. Report to the Department of the Environment, Water, Heritage and the Arts, Australian Government. 75 pp. (as Pristis microdon)
Whitty, J.M., Phillips, N.M., Thorburn, D.C., Simpfendorfer, C.A., Fielde, I., Peverell, S.C. & Morgan, D.L. 2014. Utility of rostra in the identification of Australian sawfishes (Chondrichthyes: Pristidae). Aquatic Conservation: Marine and Freshwater Ecosystems 24: 791–804.
Wueringer, B.E. 2012. Electroreception in Elasmobranchs: Sawfish as a Case Study. Brain Behav Evol 80: 97-107
Wueringer, B.E., Squire,L.J. & Collin, S.P. 2009. The biology of extinct and extant sawfish (Batoidea: Sclerorhynchidae and Pristidae). Rev. Fish Biol. Fish. 19: 445–464.
Wueringer, B.E., Peverell, S.C., Seymour, J.E., Squire, L.J., Kajiura, S.M. & Collin, S.P. 2011. Sensory systems in sawfishes: Part 1 the ampullae of Lorenzini. Brain Behav. Evol. 78: 139–149.
Wueringer, B., Peverell, S.C., Seymour, J., Squire, L., Collin, S.P. 2011. Sensory Systems in Sawfishes. 2. The Lateral Line. Brain Behav. Evol. 78: 150-161.
