Not just Shark
Pictures: Elasmodiver contains photos of sharks, skates, rays, and
chimaera's from around the world. Elasmodiver began as a simple web
based shark field guide to help divers find the best places to
encounter the different species of sharks and rays that live in
shallow water but it has slowly evolved into a much larger project
containing information on all aspects of shark diving and shark
There are now
more than 5000 shark pictures and sections on shark evolution,
biology, and conservation. There is a large library of reviewed
shark books, a constantly updated shark taxonomy page, a monster
list of shark links, and deeper in the site there are numerous
articles and stories about shark encounters. Elasmodiver is now so
difficult to check for updates, that new information and pictures
are listed on an Elasmodiver Updates Page that can be accessed here:
flattened sharklike body. Elongated flattened rostrum (saw) with 18 to 23 pairs of
evenly spaced rostral teeth. Anterior pair of rostral teeth angled forward. Base
of rostrum wide hence vernacular: Broadbill Sawfish. First dorsal fin originates
in front of
pelvic fins. Distinct lower caudal lobe.
Maximum length 5m. At birth approx 50cm.
Sand and mud bottoms in mildly saline estuaries, rivers, and lagoons. Freshwater
Sawfish is a misnomer. It spends its first 3-4 years in freshwater growing to
about half its adult size. Adults penetrate from weakly saline estuaries into
fresh water rivers(up to 100km from the sea) . Individual sawfish may be cut off
in small ponds for years at a time between floods. In Australia it is confined
to large freshwater river drainages.
Abundance and distribution:
Considered critically endangered by the IUCN red list 2006 survey.
Freshwater Sawfish are known in Australia from the Fitzroy River system in WA to
the western side of the Cape York Peninsula. Also reported from Papua New Guinea
and parts of Indonesia, and Irian Jaya. May also occur in India or even
into schools of fish and thrashes its saw from side to side, wounding and
killing the fish which it then recovers. May also use its saw to dig for crustaceans
and mollusks in the sediment.
The largetooth sawfish may reproduce in fresh water. Gestation period approx 5 months. Litter
size 1 to at least 12. Young are born with flexible rostrums in which the teeth are covered
with a sheath of skin to avoid injury to the mother. After birth the
rostrum straightens and hardens.
The Green Sawfish has a minimum of 24 pairs of rostral teeth that a more closely
spaced towards the point of the saw. The Dwarf
Sawfish (Pristis clavata) has a rounder head and evenly spaced rostral teeth,
the Narrow Sawfish (Anoxypristis cuspidata) has a much narrower rostrum.
Reaction to divers:
Unknown. Probably moves away. The photographed individual was difficult to
approach in an aquarium situation. May use its rostrum in defense if cornered
which could cause a severe injury.
There are no locations that I know of where divers can reliably find Freshwater Sawfish due to their rarity and preference for turbid
estuarine and river environments.
Any information on sightings of this species by divers, fishermen, and hikers would be very
Other diving locations submitted by readers:
Field Identification Guide to Western Australia - Sharks and
Shark-like Rays. Department of Fisheries
Australian Department of the Environment and Heritage. DEH
Species Profiles - Freshwater Sawfish.