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Frequently Asked Questions
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1. What are sawfishes?
Sawfishes are large shark-like rays with long, flat, tooth-studded snouts. They comprise the family Pristidae.
2. What are rays?
Rays are a group of specialized sharks modified for life on the bottom; rays branched off from sharks during the Jurassic period. Rays are generally flattened, and have many anatomical features which distinguish them from sharks:
Sharks Rays
Pectoral fins attach to head behind gill slits Pectoral fins fused to head before gill slits
Jaws firmly attached to skull Jaws only loosely attached to skull
Gill slits on side of head Gill slits on underside
3. Where do sawfishes live?
Sawfishes inhabit very shallow coastal and freshwater habitats in the tropics and subtropics. They prefer very muddy water where rivers empty out into the sea (estuaries). Some species appear to spend much of their lives in freshwater, entering rivers and lakes in many parts of the world. In the United States, sawfishes are only prevalent in southern Florida.
4. How big do sawfishes get?
Sawfishes are born about 2 feet long. They reach maturity in about ten years at 10 feet in length. If they reach maximum size, sawfishes can grow to over 23 feet.
5. How long do sawfish snouts (rostra) get?
A newborn sawfish has a snout about 6 inches long. The snout of a large adult sawfish can grow to at least 5.4 feet long [based on the largest rostrum I have personally examined].
6. What is the snout used for?
Sawfishes use their unique snouts for at least four purposes:
First, we know from observations of both wild and captive sawfishes that the rostrum is used as a weapon to injure small fishes. Sawfishes launch into schools of small fishes like mullet, swinging their toothy saw rapidly from side to side. Fishes are gouged by the sharp awl-shaped teeth, and stunned or injured, tumble to the bottom. The sluggish sawfish can then eat them at its leisure.
Second, sawfishes use their sensitive snouts to probe muddy or sandy bottoms for food. Like the snouts of other sharks and rays, the sawfish rostrum is covered with a network of tiny pores which are sensitive to minute electric currents and movement. Thus, even in murky water at night, sawfishes can sense animals swimming and crawling around them, and even feel the heartbeats of buried prey (heartbeats are triggered by electrical signals).
Third, once a prey animal is located, sawfishes use their toothy snouts like a clamrake, lifting invertebrates like crabs and shrimp from the substrate to eat.
Finally, when threatened, sawfishes will swing their formidable weapon to fend off enemies.
7. Are sawfishes and sawsharks the same animal?
No. Sawfishes are large shark-like rays which inhabit tropical coasts, estuaries, rivers, and lakes. Sawsharks, which comprise the family Pristiophoridae, are a group of small sharks which look much like sawfishes but are completely unrelated to them. Sawsharks inhabit very deep off-shore waters in many parts of the world. They are even more poorly known than sawfishes, but appear to have a similar lifestyle, using their rostrum to stun small fishes and root up invertebrates. Sawsharks are substantially smaller than sawfishes (reaching only 5 feet in length), but look very similar to them. Sawsharks differ from sawfishes in several ways, including:
Sawshark Sawfish
Shark Ray
Triangular snout Snout sides more parallel
Rostral teeth of many sizes Rostral teeth of similar size
Rostral teeth attached by connective tissue Rostral teeth embedded deep in rostrum
Rostral teeth extend past eye Rostral teeth do not extend to eye
Sensory barbels on underside of snout No sensory barbels
Deep water off-shore habitat Shallow coastal habitat
Maximum size 5 feet Maximum size 23 feet
Family Pristiophoridae Family Pristidae
Gill slits on side of head Gill slits on undersurface
8. Are sawfishes prehistoric?
Despite their ‘prehistoric’ appearance, sawfishes actually evolved quite recently. The rays first appeared during the Jurassic period, 163 million years ago during the ‘Age of Dinosaurs’. True sawfishes emerged later, during the Eocene epoch (in the modern era) only 56 million years ago. In comparison, the first horses, whales, and bats appeared during this same period, mammals which we generally think of as quite ‘modern’.
9. What do sawfishes eat?
Sawfishes eat a variety of small fishes and invertebrates which can be taken whole through the mouth. Schooling fishes (like mullet), crabs, and shrimp are favorite prey. Despite accounts to the contrary, sawfishes never eat animals they cannot fit into their small mouths, as their blunt pavement-like teeth are incapable of tearing chunks off like sharks. Sawfishes never attack whales or people or boats.
10. Are sawfishes dangerous to humans?
No. Sawfishes are very sluggish and docile, and all too often can be captured with amazingly little effort given their immense size. If threatened or injured, sawfishes will of course defend themselves, smacking attackers with their toothy saw, so sawfishes should be approached with caution. After a decade of research into these animals, I have never encountered one verifiable record of a sawfish killing or even seriously injuring a human.
11. Do any animals eat sawfishes?
Generally, few predators would approach a large sawfish unless it is caught in a net or injured. Baby sawfishes are in more danger of predation, and sawfish remains have been found in crocodiles, sharks, and even dolphins. A section of a large sawfish snout was once found inside a tiger shark; definitely sounds like a meal that would give you a stomachache.
12. How do sawfishes reproduce and how many babies do they have?
Sawfishes practice internal fertilization; males mate using a pair of rod-like organs called claspers. Sawfishes are ‘ovoviviparous’, meaning that baby sawfishes grow in soft eggs which develop inside the mother. Sawfishes give live birth, with an average litter size of 8 pups. Few details are known about when and where sawfishes mate or give birth. One study of freshwater sawfishes in Lake Nicaragua suggests that sawfishes mate every other year, and give birth in shallow water.
13. Are sawfishes in danger?
Because few people are familiar with sawfishes, they are surprised to hear that sawfishes are endangered. Given their shallow coastal habitat, sawfishes can be easily impacted by human activity. Areas where sawfishes live can be modified or polluted, making the area unsuitable for these remarkable rays. In addition, sawfish populations plummet when net-fishing occurs in their habitat. Their toothy saw is easily entangled in nets set for other fishes, leading to many accidental sawfish deaths.
Organizations such as the International Union for the Conservation of Nature (IUCN) and the National Marine Fisheries Service (NMFS) are concerned about endangered sawfish populations, and are attempting to enact legislation to protect sawfishes and minimize the threats to their existence. Countries such as the United States and Australia are conducting scientific studies to determine where healthy populations still exist, and to collect more information about sawfish life history. Using this data, scientists can recommend the best methods to save sawfishes from extinction.
** On April 1st, 2003, the NOAA / NMFS officially listed smalltooth sawfishes (Pristis pectinata) to the U.S. Endangered Species Act. Effective May 1, 2003, it will now be prohibited to harass, injure, take, capture, or collect pristids in U.S. waters, or modify their habitat.
It will also be prohibited to buy or sell smalltooth sawfishes or sawfish parts (snouts) in America. Under this legislation, the U.S. government will now create an action plan to conserve endangered popualtions of sawfishes in U.S. territory, and they will seek to designate and protect habitats critical to these threatened elasmobranchs.
14. Can you recommend good general books on sawfishes?
Unfortunately, our knowledge of sawfishes is limited, and many people are still unaware that they exist. Thus, there are very few books available which discuss these unique rays. The sources listed in the REFERENCES page of this website are mainly scientific articles, difficult to obtain if you do not have access to a university library.
One good general guide to sharks and rays is the book:
Taylor, L.R., ed. (1997). Sharks and Rays. The Nature Company Guides. Weldon Owen Inc, Sydney, 288 p.
This book has information about sawfishes and includes several nice photographs. The Nature Company's Sharks and Rays is available at many major bookstores and public libraries.
15. Where can I find sawfish toys and merchandise?
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15' 5" [4.7 m] smalltooth sawfish caught by William Bloyd in Florida Bay in 1961.
Photo courtesy of www.FloridaSawfish.com
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Three smalltooth sawfishes taken near Naples, FL in 1928.
Photo courtesy of www.FloridaSawfish.com
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10 ft. Smalltooth Sawfish (Pristis pectinata) caught by Rick Haveland's Captain Hook Charters, near Key West, FL, June 27, 2002.
http://www.captainhookcharters.com/Sawfish.shtml
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