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South Florida Aquatic Environments About the Different Groups of Fishes About the Anatomy of Fish and Sharks How Fish and Sharks Swim About Fish Adaptations About the Endangered Species Act How to Become a Biologist About Careers In Ichthyology Most Commonly Asked Shark Questions Most Commonly Asked Sawfish Questions Most Commonly Asked Ray and Skate Questions Most Commonly Asked Fish Questions Identification Key to Freshwater Fishes of Peninsular Florida Field Key to Sharks Skates of the Western Gulf of Maine Project Shark Awareness - A Public Outreach Educational Program Shark Fishing in U.S. Territorial Waters Most Commonly Asked Sawfish Questions Sawfish In Peril - PowerPoint file Sawfish Informational Brochure - Acrobat file Sawfish Outreach Boat Ramp/Marina Sign - Acrobat file Sawfish In The News Sawfish References Sawfish Links Smalltooth Sawfish species profile Largetooth Sawfish species profile Green Sawfish species profile Freshwater Sawfish species profile Dwarf Sawfish species profile Knifetooth Sawfish species profile Chondrichthyes Bibliography Search Freshwater Fishes of Florida References General Fish References Shark References Sawfish References Childrens' Shark Books Stingray Reproduction References Biological Profiles Glossary of Terms Shark Games: Test Your Knowlege! 2003 Open House Photos LARGETOOTH SAWFISH Order - Pristiformes Family - Pristidae Genus - Pristis Species - perotteti Taxonomy The currently valid scientific name for the largetooth sawfish is Pristis perotteti (Müller & Henle, 1841). The genus name Pristis is derived from the Greek word "pristis" which means saw. The specific name perotteti is named after the French naturalist M. Perrottet who obtained the type specimens. A common synonym that has been used in past scientific literature is Pristis pristis Linnaeus 1758, which was taken probably not based upon any particular species of sawfish but rather treated sawfishes as a whole. Pristis microdon Latham 1794 has appeared as a misidentification and Pristis perrotteti as a misspelling. The taxonomy of the largetooth sawfish has been difficult to determine due to a lack of adult specimens, questionable identifications, and the number of synonyms that have been used in past scientific literature which remain to be resolved. Presently, there is difficulty in determining how many valid species within the genus Pristis actually exist. Common Names Common names for this species include largetooth sawfish, large-tooth sawfish, southern sawfish, common sawfish, freshwater sawfish, sawfish, saw fish (English); stortandet savrokke (Danish); billi sovulu, chakku thatte, naithatte (Kannada); makara sravu, vala sravu, velli sravi (Malayalam); hachutti meenu, shinesi (Telugu); iluppa, vela (Tamil); catanuda, pez espada, pez peine, pez rastrillo, pez sierra, sierra (Spanish); araguagua, peixe-serra (Portuguese); zaagvis, groottandzaagrog (Dutch); krarien, and sartji (Sranan). Geographical Distribution Only the largetooth sawfish (P. perotteti) and its close relative the smalltooth sawfish (P. pectinata) are found in the western Atlantic Ocean. Both species have been adversely impacted by decades of overfishing. Historically, largetooth sawfish were found in warm tropical and sub-tropical marine, estuarine, and contiguous freshwater habitats in the Atlantic Ocean and along the tropical and subtropical Pacific coasts of the Americas. It is believed that largetooth sawfish once occurred in the eastern Mediterranean Sea and in freshwater of Africa as well as almost certainly still occurring in North, Central and South America. There was a freshwater population of largetooth sawfish in Lake Nicaragua (Central America) that had been studied over a long period of time until it was virtually depleted by 1981 due to overfishing. Historically, occurrences of largetooth sawfish in North America have been much less frequent than that of the smalltooth sawfish. Largetooth sawfish had been typically found in shallow coastal waters less than 33 feet (10 meters) deep, in estuaries and lagoons, and often found to have travelled great distances up rivers. While reports of the species in U.S. waters are now rare, largetooth sawfish have been seen along the Texas coast to the Louisiana line. Evidence does not support that this species ever regularly occurred in Florida waters. Southeastern United States waters are most likely the northernmost limit of the largetooth sawfish's historic range. World distribution map for the largetooth sawfish Habitat Sawfish in general inhabit the shallow coastal waters in tropical, subtropical and warm-temperate waters. They are typically found very close to shore lying on muddy and sandy bottoms, in bays, estuaries, and lagoons. Generally thought to rarely descend to depths greater than 33 feet (10 meters ), sawfish have been found in water to 400 feet (122 meters) deep in Lake Nicaragua. Biology Largetooth sawfish side view without the rostral saw Bigelow and Schroeder (1948) FNWA Largetooth sawfish dorsal view Bigelow and Schroeder (1948) FNWA · Distinctive Features While they swim much like sharks, sawfish are actually a species of ray. Included in the group of fishes known as elasmobranchs, sawfish have cartilaginous skeletons. The head is ventrally flattened with the mouth located underneath and the eyes positioned dorsally. Sawfish are able to breath while lying on the ocean floor by drawing water into their gills through large holes behind each eye, called spiracles. Their most distinctive feature is their long flat rostrum - "saw" - that is lined with rostral teeth along the margins. These "teeth" are set deeply in hard cartilage and do not grow back if the root becomes damaged. Largetooth sawfish rostral saw Bigelow and Schroeder (1948) FNWA Comparison of smalltooth sawfish saw on left and largetooth sawfish saw on right The largetooth sawfish and the smalltooth sawfish (P. pectinata) are similar in appearance with overlapping ranges in the western Atlantic Ocean and parts of the eastern Atlantic Ocean. The two species can usually be differentiated by noting the number of teeth on one side of the rostrum. P. perotteti can have between 14-21 rostral teeth on one edge of the saw whereas P. pectinata usually has 23-34. These two species can also be distinguished by observing that in P. perotteti the first dorsal fin originates anterior to the pelvic fins while in P. pectinata the first dorsal fin originates along the same axis as the pelvic fins. The pectoral fins of P. perotteti are proportionally larger than those of P. pectinata. Furthermore, only P. perotteti has a distinct lower lobe on its caudal fin. · Coloration P. perotteti caught in saltwater are dark gray to golden brown in color. Freshwater specimens are mouse gray with red coloration around the back, lower sides, second dorsal, pelvic fins, and caudal sides. The first dorsal may have pale yellow coloration with a reddish rear tip. The reddish tint may be normal or a result of suffusion with blood below the skin. Teeth from the rostral saw of a largetooth sawfish Bigelow and Schroeder (1948) FNWA ·Dentition The teeth of the largetooth sawfish are dome-shaped anteriorly with an obtuse cutting edge. These teeth are a bit larger than in the smalltooth sawfish, with about 12 functional rows in each jaw. The number of teeth increases as the sawfish matures. Newborn largetooth sawfish have 70 teeth and larger individuals have approximately 80-90. Denticles from below the first dorsal fin of a largetooth sawfish Bigelow and Schroeder (1948) FNWA ·Denticles Dermal denticles of P. perotteti are more widely spaced over the upper surface than in P. pectinata. The blades are ovoid in shape and rather strongly oblique. The bases are roughly four-cornered and are evident through the skin in very young specimens but more concealed in larger specimens. The denticles on the saw of P. perotteti are rounded to oval and are so closely crowded, they conceal the skin entirely. The denticles along the margins of this fish are the largest; those on lower surface are similar to those on the upper surface but are more closely crowded. ·Size, Age, and Growth Maximum size of P. perotteti has been reported between 20.0-21.2 feet(6.1-6.5 m) total length and between 1,102-1,323 pounds (500-600 kg) in weight. P. perotteti are believed to mature around 10 feet (3 m). Largetooth sawfish grow slowly, reaching maturity late at 10 years of age and producing few young. As a result, their population growth is extremely low. Although lifespan in the wild is unknown, research suggests this species lives roughly 30 years. · Food Habits Largetooth sawfish feed on benthic crustaceans and other invertebrates it stirs up from the substrate with its saw. The saw may also be used to disable prey by stunning small schooling fish such as mullet and smaller herrings before consuming them. · Reproduction P. perotteti is ovoviviparous. It's eggs are retained in the uterus and the embryos develop while being nourished by a yolk sac. The young are fully developed at birth and litters consist of 1-13 young with 7-9 being the most frequent litter size. Nicaraguan specimens have been recorded as 2.5 feet (76 cm) TL at birth. Litters may be produced every other year. The mating season for the Lake Nicaragua population of largetooth sawfish is early June to July, gestation lasts approximately five months, with young born from October to December. The sawteeth of young sawfish do not fully erupt, and are covered by a sheath of tissue until after birth to protect the mother during the birthing process. The American crocodile is a predator of the largetooth sawfish Everglades National Park Photo · Predators It has been reported that predators of the largetooth sawfish include the American crocodile (Crocodilus acutus). Sawfishes (Pristis spp.) have been preyed upon by copper sharks (Carcharhinus brachyurus), bull sharks (Carcharhinus leucas), and tiger sharks (Galeocerdo cuvier). Sawfishes may also fall victim to red tides. Red tide (Karenia brevis) is a local phenomenon in the Gulf of Mexico, along the Florida coast, and impacts many species of fish and wildlife. Largetooth sawfish saws have long been used by humans in a variety of purposes Importance to Humans Worldwide, sawfish saws have long been sold as trophies or curios. Historical uses of sawfish products have included the rostra being used in religious offerings and traditional medicine. The rostral teeth of the sawfish have been hand crafted into tools or attached to the legs of fighting birds used in cockfights. Sawfish meat has been harvested for human consumption and is reported to be white and tender. Today, sawfish fins are more valuable than the meat and have been sold in the Asian 'shark fin' trade. Some cultures believe tea made from the saws aid in treating asthma. Largetooth sawfish can use their saws for self defense © Jason Seitz Danger to Humans Unprovoked, the sawfish is considered very docile. Captured sawfish should be handled with care however, as their saw can be used for defense in powerful side-to-side motions. Largetooth sawfish harvest Conservation Because of the rostrum that makes them so unique, sawfish are especially vulnerable to incidental capture in fishing nets and are difficult to remove safely. Habitat degradation very likely impacts the species due to their tendency to inhabit shallow water near shores and estuaries. The population in Lake Nicaragua has suffered greatly from over fishing. On April 1, 2003 the U.S. National Marine Fisheries Service placed the smalltooth sawfish (P. pectinata) on the Endangered Species List, making it the first marine fish species to receive protection under the Endangered Species Act. National Marine Fisheries Service stated that substantial information in the petition for the largetooth sawfish was not presented for the largetooth sawfish which currently remains on the candidate species list.The World Conservation Union (IUCN) declared the family Pristidae to be "among the most threatened elasmobranches" in the world with the largetooth sawfish currently listed as "Critically Endangered". The IUCN is a global union of states, governmental agencies, and non-governmental organizations in a partnership that assesses the conservation status of species. Prepared by: Taylor Sullivan