SAWFISH IN PERIL

FLORIDA PROGRAM FOR SHARK RESEARCH

Florida Museum of Natural History

Sawfish In PerilMost Commonly Asked Sawfish Questions

•Sawfish Basics

•Sawfish Biology

•Sawfish Conservation

•Sawfish Research © Doug Perrine

SAWFISH BASICS

© Doug Perrine

What is a Sawfish?

• Sawfish belong to the Family Pristidae

• Sawfish are characterized as having an elongate blade-like snout (rostrum or saw) that has laterally placed tooth-like denticles (rostral teeth)

How many species of sawfishes are there?

• There are 6-7 species of sawfishes currently recognized by scientists

• Biologists are currently reviewing the taxonomy of sawfishes, some species are similar in appearance

© Doug Perrine

How large can sawfishes grow?

• Smalltooth sawfish commonly reach 18 feet in length, attaining a maximum length of 24.7 feet

© George Burgess

Do sawfishes live off the coast of the U.S.?

• The smalltooth sawfish is only found off the Atlantic and Gulf coasts of Florida

• The largetooth sawfish is limited to the Gulf of Mexico

• The rostral “saw” is used for feeding, slashing back and forth in the soft sediments in search of invertebrates and to stun schooling fishes

• The “saw” is also used as defense against predators

Why do sawfishes have that remarkable tooth-studded saw?

© George Burgess

Do sawfishes present a threat to humans?

• Sawfishes are harmless to humans if left undisturbed

• Care must be taken when handling sawfishes as they may defend themselves with the rostral “saw”

SAWFISH BIOLOGY

© Don DeMaria

Do sawfishes have bones?

• No, sawfishes and other fishes belonging to the Class Chondrichthyes lack true bone, but rather have cartilaginous skeletons (sharks, skates, and rays)

• Bony fishes (Class Osteichthyes) have true bones as do humans - see photo above

U.S. Geological Survey

How many fins do sawfishes have?

Pectoral FinsPelvic Fins

Dorsal FinsCaudal Fin

• They have two pectoral fins (fused to the head/trunk), two pelvic fins, two dorsal fins, and a caudal fin

• Like the great majority of rays, sawfishes lack an anal fin

How long do sawfishes live?

• It has been estimated that these animals live up from 30 to 60 years

What do sawfishes eat?

• Sawfishes feed on small fishes and invertebrates that can be ingested whole through the mouth

• They only feed on prey that can fit into their small mouths since they are unable to tear chunks off prey items with their toothy saw

© Doug Perrine

Do sawfishes have any predators?

• Adult sawfishes have very few predators

• Juvenile sawfishes are preyed upon by crocodiles, large sharks, and even marine mammals such as dolphins

© Doug Perrine

Do sawfishes have teeth in their jaws?

• Ten to twelve rows of teeth are located in jaws of the smalltooth sawfish

• The teeth are rounded anteriorly and have a blunt cutting posterior edge

© George Burgess

Do sawfishes lay eggs or give live birth to young?

• Sawfishes are "ovoviviparous", meaning that young sawfishes grow from eggs retained within the mother

• After the embryos are fully developed, the mother sawfish gives live birth with an average litter size of about 8 pups

SAWFISH CONSERVATION

Are sawfishes listed as threatened or endangered in the U.S.?

• On April 1, 2003 the U.S. National Marine Fisheries Service placed the smalltooth sawfish on the Endangered Species List, making it the first marine fish species to receive protection under the Endangered Species Act

What are some threats to sawfishes?

• Entanglement in fishing gear and marine debris

• Indirect take as by-catch in other directed fisheries

• Loss of habitat, coastal development and marine pollution

• Use of saws as curios and the fins for soup

U.S. Geological Survey

What should you do if you encounter a sawfish in its natural

habitat?

• Sawfish are listed under the Endangered Species Act which makes it illegal to harm, harass, or handle them in any way

• If you do see a sawfish, enjoy the moment and feel extremely lucky!

© Doug Perrine

Are sawfishes ever accidentally caught?

• Sawfish are sometimes accidentally caught on fishing hooks and in fishing nets

• If a sawfish is accidentally caught, it should be released immediately to ensure its survival

© Doug Perrine

Is it difficult to safely release a captured sawfish?

• Sawfish are sometimes accidentally caught on fishing lines and in fishing nets or entangled in marine debris

• Guidelines are available on what to do if a sawfish is hooked or if a sawfish is tangled in a net

• Encounters should be reported to the National Sawfish Encounter Database to assist with ongoing scientific research

Did fishermen catch sawfishes prior to their protection in the U.S.?

• Sawfish were often caught by fishermen who would sometimes eat the flesh and keep the trophy “saw”

• Very large sawfishes were often captured in past decades

SAWFISH RESEARCH

What do scientists still need to learn about sawfish?

• Scientists are researching age and growth, reproduction, movement patterns, and habitat use of the smalltooth sawfish to assist in management and recovery of this endangered species.

What is the National Sawfish Encounter Database?

•Records and maintains a database of sawfish sightings

•http://www.flmnh.ufl.edu/fish/sharks/sawfish/sawfishdatabase.html

Sawfish Reporting Form

•Interactive Online Sawfish Reporting Form

•http://www.flmnh.ufl.edu/fish/sharks/sawfish/form.html

What are some good resources to learn more about sawfishes?

• There are some good web sites, scientific journals, and books to learn more about sawfishes

Questions/Answers?