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Family Pristidae The Sawfish

Family Pristidae The Sawfish. Greek pristis = saw Sara McCutcheon. General Characteristics. Large toothed rostrum Body shark-like 2 distinct dorsal fins and caudal fin Pectoral fins distinct Depressed head. Sawfish vs Sawshark Eye. Sawfish vs Sawshark Rostrum teeth.

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Family Pristidae The Sawfish

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  1. Family PristidaeThe Sawfish Greek pristis = saw Sara McCutcheon

  2. General Characteristics • Large toothed rostrum • Body shark-like • 2 distinct dorsal fins and caudal fin • Pectoral fins distinct • Depressed head

  3. Sawfish vs SawsharkEye

  4. Sawfish vs SawsharkRostrum teeth

  5. Sawfish vs SawsharkGill Position

  6. Sawfish Taxonomy7 species in 2 Genera • Pristis pristis – Common sawfish • Pristis perotteti – Largetooth sawfish • Pristis microdon – Freshwater sawfish • Pristis pectinata – Smalltooth sawfish* • Pristis clavata – Dwarf sawfish • Pristis zijsron – Green sawfish • Anoxypristis cuspidata – Knifetooth sawfish

  7. Anoxypristis cuspidata (1 sp.) Taxonomy7 species in 2 Genera Pristis pristis complex (3 spp.) Pristis pectinata complex (3 spp.)

  8. 3 Types of Sawfish Pristis pectinata complex • Non-tapering rostrum • Smaller teeth • 22-32 teeth per side Pristis pristis complex • Broad tapering rostrum • Larger teeth • 15-20 teeth per side Anoxypristis cuspidata • Very narrow saw • No teeth on the closest quarter of rostrum to head • 16-29 teeth per side • More flattened and triangular teeth

  9. Habitat • Benthic • Freshwater, brackish, and marine • Nearshore waters • Bays, lagoons, rivers, lakes, estuaries, seagrass, and reefs • Sandy and muddy substrate

  10. Distribution • Nearshore waters • Tropical, subtropical and warm temperate • Atlantic, Indian, and Pacific

  11. Biology • Conicospiral intestines and long pyloric stomachs • 3 reported instances of intestinal eversion (first non-carcharhinid) • Juveniles prefer a depth of 10m or less; adults deeper water • Some species use freshwater nurseries for ~4-5 years • Immature up to 280cm • Max size 760 cm TL – P. pectinata (350kg) • Max recorded weight 600kg – P. microdon • Max age 30 years

  12. Reproductive Biology • Sexual maturity is reached at 10-11 feet for males and 11-12 feet for females • Ovoviviparous • Gestation of ~ 5 months • Litter every other year • 6-23 pups • Pupping occurs in spring (wet season) • Born at 2 feet long • Born backwards, saw encased in a sheath of tissue, and teeth do not fully erupt until after birth

  13. Diet • The saw is used to catch, kill, and manipulate food  • Swipe the saw, stunning or impaling fish • Small sawfish – crustaceans and fish • Large sawfish – fish (jacks, mullet, ladyfish)

  14. Threats Fishing and Habitat Loss and degradation

  15. Fisheries • In the late 1800s a fisherman on the Indian River in Florida reported that he caught more than 300 sawfish in one season

  16. Fisheries • Recreational fisheries for saw trophy • Commercial fisheries bycatch, saw entanglement

  17. Fisheries • Chinese medicine – eggs, liver, oil, bile • Food • Shark fin soup • Decoration • Leather • Curio trade • Saw for spiritual offerings

  18. Habitat Loss and Degradation • Extensive coastal development • Dredging • Mangrove removal • Seawall construction • Alteration of freshwater flow • Habitat fragmentation

  19. Status • All 7 sawfish species are critically endangered • P. pectinata – apparently extinct in the Mediterranean and NE Atlantic • P. perotteti – extirpated from most of its range in Atlantic • P. pristis – was once common in the Mediterranean and Eastern Atlantic, but has now been extirpated from Europe and the Mediterranean • Likely to become extinct

  20. Conservation Efforts • Federally (ESA) and internationally (IUCN) protected • Research • Public education and outreach • Public sightings database • Captain’s logbooks

  21. Bibliography • Adams, W.F., Fowler, S.L., Charvet-Almeida, P., Faria, V., Soto, J. & Furtado, M. 2006. Pristis pectinata. In: IUCN 2007. 2007 IUCN Red List of Threatened Species.www.iucnredlist.org. Downloaded on 05 November 2007. • Carrier, J.C., Musick, J.A., and Heithaus, M.R.. 2004. Biology of Sharks and their Relatives. CRC Press, Boca Raton, FL. pp 142, 416, 427. • Charvet-Almeida, P., Faria, V., Furtado, M., Cook, S.F., Compagno L.J.V. & Oetinger, M.I. 2007. Pristis perotteti. In: IUCN 2007. 2007 IUCN Red List of Threatened Species. www.iucnredlist.org. Downloaded on 05 November 2007. • Compagno, L.J.V., Cook, S.F., Oetinger, M.I. & Fowler, S.L. 2006. Anoxypristis cuspidata. In: IUCN 2007. 2007 IUCN Red List of Threatened Species.www.iucnredlist.org. Downloaded on 05 November 2007. • Cook, S.F., Compagno, L.J.V. & Last, P.R. 2006. Pristis clavata. In: IUCN 2007. 2007 IUCN Red List of Threatened Species. www.iucnredlist.org. Downloaded on 05 November 2007. • Deynat, PP. 2005. New data on the systematics and interrelationships of sawfishes (Elasmobranchii, Batoidea, Pristiformes). Journal of Fish Biology 66 (5):1447-1458. • Florida Museum of Natural History – Icthyology. http://www.flmnh.ufl.edu/fish/Gallery/Descript/DwarfSawfish/DwarfSawfish.html. Viewed on 11/06/07. • Henningsen, AD, Whitaker, BR, and Walker, ID. 2005. Protrusion of the valvular intestine in captive smalltooth sawfish and comments on pristid gastrointestinal anatomy and intestinal valve types. Journal of Aquatic Animal Health 17 (3): 289-295. • Mote Marine Laboratories. www.mote.org. Viewed on 11/06/07. • Nelson, J.S. 2006. Fishes of the World, 4th ed. John Wiley and Sons, Inc, NJ. pp 69, 73. • Peverell, SC. 2005. Distribution of sawfishes (Pristidae) in the Queensland Gulf of Carpentaria, Australia, with notes on sawfish ecology. Environmental Biology of Fishes 73 (4): 391-402. • Robillard M. and Seret, B. 2006. Cultural importance and decline of sawfish (Pristidae) populations in West Africa. Cybium 30 (4): 23-30. • Thorburn, DC, Morgan, DL, Rowland, AJ, and Gill, HS. 2007. Freshwater sawfish Pristis microdon Latham, 1794 (Chondrichthyes : Pristidae) in the Kimberley region of Western Australia. Zootaxa 1471: 27-41.

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