Effective January 12, 2015, the narrow sawfish (
Anoxypristis cuspidata), dwarf sawfish (
Pristis clavata), largetooth sawfish (
Pristis pristis), green sawfish (
Pristis zijsron), and the non-U.S. distinct population segement of smalltooth sawfish (
Pristis pectinata) will be designated as endangered species under the Endangered Species Act (ESA) of 1973.
The National Marine Fisheries Service (NMFS) received a petition on September 10, 2010 from the WildEarth Guardians requesting NMFS to list six sawfish species as endangered or threatened under the ESA. On June 4, 2013, NMFS proposed to list five of the six species as endangered based on a current extinction risk assessment, threats affecting the status of each species, and efforts currently being made to protect each species.
Sawfish are a group of rays, order
Rajiformes, with a body shape reminiscent of sharks but flattened dorso-ventrally with enlarged pectoral fins. They have a large, flat, toothed rostrum that they use to locate, stun, and kill prey. Most species of sawfish consume small schooling fish, crustaceans, and other benthic species and occupy the mid- to upper-levels of the food web. Various species of sawfish are distributed globally, but primarily inhabit shallow, tropical coastal waters. They can survive in variable salinities, including freshwater, some sawfish even have established populations in majors rivers and lakes in South America, Africa, Australia, and Southeast Asia.
The Narrow sawfish (
Anoxypristis cuspidata) is characterized by a narrow rostral saw, which lacks teeth on the first quarter of the saw closest to its head, a distinct shape of the lower lobe of the caudal fin, and dagger-shaped rostral teeth. Narrow sawfish are the only sawfish with tricuspid denticles, and adults often only have sporadic denticle coverage, with denticles found on the rostrum and anterior fin margins. This species of sawfish is euryhaline and frequently moves between estuarine and marine environments, while keeping to shallower habitats. They are found throughout the eastern and western portions of the Indian Ocean as well as the western Pacific Ocean. Age and size at maturity ranges between 2 to 3 years and 8ft to15ft, they can theoretically live for 27 years. Historically a commonly sighted species, the narrow sawfish has undergone dramatic declines and is a rare catch by both commercial and recreational fishermen.
Dwarf sawfish (
Pristis clavata) are very similar to largetooth sawfish and are distinguished by their rostral tooth morphology. Their rostrums are short with 19 to 23 rostral teeth that are moderately flattened, elongated, and peg-like. The pectoral fins of this species are also small compared to other sawfish. This species of sawfish has been found in mostly marine and estuarine habitats, but they have also been reported up to 31 miles upstream in the south Alligator River, Northern Territory, Australia. Dwarf sawfish have commonly been considered small compared to other sawfish, with an average size around 4 ft, but recently larger specimens have been found with lengths over 19ft. Their theoretical maximum age is 94 years. Dwarf sawfish appear to have been extirpated from the Indo-Pacific region and eastern coast of Australia, they are now considered rare in the Gulf of Carpentaria, and it is likely that the Kimberley and Pilbara regions of western Australia are the last remaining areas for dwarf sawfish.
Largetooth sawfish (
Pristis pristis) have a robust rostrum that widens posteriorly. They are found in coastal and inshore waters and are considered a euryhaline species. Sometimes found upriver, they can inhabit freshwater lakes and pools, and are associated with freshwater more than any other sawfish species. Size and age at maturity averages around 10 ft, 8 years. The largest recorded largetooth sawfish was 22ft 11in. Historically largetooth sawfish occurred throughout the Indo-Pacific near southeast Asia and Australia, and throughout the Indian Ocean to east Africa. Current reports of this species indicate that global populations have been severly fragmented into isolated populations of low abundance. Sightings are very rare and usually in remote areas.
Green sawfish (
Pristis zijsron) has a narrow saw with small, slender rostral teeth and is a greenish brown color dorsally. While mostly an inshore, marine species, green sawfish have been found as far as 149 miles upriver. Adults often reach 16 ft but can grow as large as 23ft, with a theoretical maximum age of 53 years. The green sawfish has historically inhabited the Indo-West Pacific from South Africa northward along the east coast of Africa and east to Asia up to southern China. Due to lack of data the current range and abundance of this species is difficult to determine, but the lack of records in areas where the species was historically found suggests that the species is no longer present or has declined to extremely low levels. Now, green sawfish are primarily found in northern Australia but it is known that these populations have undergone significant declines.
Smalltooth sawfish (
Pristis pectinata) has a thick body with a moderately sized rostrum, and a not well defined caudal lobe. Generally found in shallow waters of varying salinity, they remain mostly in warm, coastal waters particularly areas with red mangroves. Smalltooth sawfish were thought to inhabit waters around South Africa, Madagascar, the Red Sea, Arabia, India, the Philippines, west Africa, South America, the Mexican Gulf of Mexico, and Bermuda. However, reports of smalltooth sawfish from other than the Atlantic Ocean are likely cases of misidentification. In the Atlantic Ocean this species is found along the west coast of Africa from Angola to Mauritania, the United States coast, and the Caribbean. Recent information shows that the distribution of smalltooth sawfish in the Atlantic Ocean is patchy and has been reduced with only a few viable populations existing outside of the U.S., with the Guinea Bissau one of the last areas in West Africa where sawfish can be found.
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