Dwarf Sawfish
Pristis clavata
Meet the dwarf sawfish, the smallest sawfish species of them all!
Credit: David Morgan www.edgeofexistence.org/species/dwarf-sawfish/
Key Features & Appearance
As its name suggests, the dwarf sawfish is the smallest of any sawfish species. They are olive-brown and can grow up to 11 feet long. However, when they reach sexual maturity at 6 to 7 years old, females become larger than males. Their eyes are located in a dorsal position, while their gills can be found on their undersides.
The sawfish is named for its flat snout, or “rostrum”, which closely resembles a man-made saw. For the dwarf sawfish, the number of teeth on its rostrum depends on its sex: males have 19-23 teeth, while females have 20-22. Despite their physical similarity to sharks, dwarf sawfishes' unique snouts make them incredibly easy to recognize!
Habitat & Distribution
In the past, dwarf sawfish were found throughout the eastern Indian, Western Pacific, and Indo-Pacific Oceans. However, the rise of commercial fishing drastically shrunk their range. Now, they are limited to north and northwest Australia, with only small populations remaining elsewhere in the Indo-Pacific area.
Dwarf sawfish are a demersal species, which means that they live close to the seafloor. They especially enjoy spending time in the bottoms of muddy and sandy waters. In particular, they are found in the shallows of estuaries and coasts, as well as certain rivers.
Diet
When it comes to hunting, dwarf sawfish have a convenient tool at their disposal: their “saws”! Though the exact use of their snouts is still debated, it is thought that sawfish use them to slash through or pin down prey. Such prey typically includes schooling fish, crustaceans, and mollusks.
Reproduction
With lifespans of more than 50 years, dwarf sawfish do not reach sexual maturity until they are 6-7 years old. Female dwarf sawfish are ovoviviparous, meaning that their eggs hatch while they are still inside the female’s body; she later gives birth to live young. For the first three years of their life, young dwarf sawfish are contained within estuaries until they are ready to become fully independent.
Credit: Peter Kyne www.sawfishconservationsociety.org/dwarf-sawfish
Threats
Like countless other species, habitat loss is a major threat to dwarf sawfish. This loss is especially alarming, given that their young use shallow waters as nurseries. Another pressing threat to dwarf sawfish is commercial fishing. Although they are not necessarily targets of the industry, they often become bycatch. It has been estimated that commercial fishing bycatch has led to a 50-80% decrease in dwarf sawfish numbers.
Nevertheless, there are certain instances in which dwarf sawfish are direct targets themselves. For instance, they are sold on the Asian “shark fin” market, usually for their liver oil and leather. They are also used for traditional Chinese medicine, particularly their liver oil, bile, eggs, and rostrum.
Status
According to the International Union for Conservation of Nature (IUCN), dwarf sawfish are listed as “critically endangered” with their numbers rapidly decreasing.
Fun Fact
Did you know that it is illegal to catch dwarf sawfish in Australian waters? Although commercial fishing bycatch still poses a major threat to them, this is a major step in protecting such a vulnerable species.
Works Cited
“Dwarf Sawfish.” EDGE of Existence, 4 Dec. 2018, www.edgeofexistence.org/species/dwarf-sawfish/.
“Dwarf Sawfish.” Sawfish Conservation Society, www.sawfishconservationsociety.org/dwarf-sawfish.
Fisheries, NOAA. “Dwarf Sawfish.” NOAA, 30 Oct. 2023, www.fisheries.noaa.gov/species/dwarf-sawfish.
International), Sonja Fordham (Shark Advocates, et al. “The IUCN Red List of Threatened Species.” IUCN Red List of Threatened Species, 11 Mar. 2022, www.iucnredlist.org/species/39390/68641215.
“Pristis Clavata.” Discover Fishes, www.floridamuseum.ufl.edu/discover-fish/species-profiles/pristis-clavata/.
“Sharks.” Pristis Clavata | Sharks, 12 Feb. 2016, www.cms.int/sharks/en/species/pristis-clavata.
“Species Profile.” ECOS, ecos.fws.gov/ecp/species/9971.