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In the Atlantic waters off the United States, the Smalltooth Sawﬁsh has declined by at least 95% relative to its abundance in the early 1900s; by the 1980s, the core distribution had contracted to southwestern Florida. At the dawn of the 20th century, this species was extremely common in waters around the southeastern United States. However, in the early 1900s, nearshore net fisheries developed in this region that resulted in large sawfish losses due to accidental bycatch as sawfishes became easily entangled in nets intended for other species. In addition, loss of wetlands critical to their reproduction accelerated with the rapid development of this region. By the 1990s, the Florida populations appeared to have stabilized (at an extremely reduced level) and today the main threats to the recovery of the species appear to be habitat loss, marine pollution, and injuries inflicted directly by humans. Factors making this species more vulnerable to population reductions include their small litter size, slow growth, and late maturity (based on the limited data available, generation time has been estimated to be around 27 years and lifespan around 30 to 60 years). However, recent genetic analyses by Chapman et al. (2011) suggest that despite the dramatic population decline, a high level of genetic diversity has been retained., i.e., no genetic bottleneck has been detected despite the demographc bottleneck. (Seitz and Poulakis 2006; Chapman et al. 2011 and references therein)
Immature Smalltooth Sawﬁsh are highly dependent on shallow inshore habitats (less than 2 m deep), especially around the mouths of rivers and in estuaries. Very young individuals occur on shallow sand and mud banks, often not leaving water less than 30 cm deep for extended periods (adults are known to occur in waters up to 100 m deep). Males mature at around 270 cm total length (TL), and females at around 360 cm TL. Litter size is thought to be 15 to 20, although data are limited. The young are born at 60 to 80 cm TL. (Simpfendorfer 2005)
Smalltooth Sawfish are not aggressive and pose no danger to humans except when they are caught and handled. The saw can be used to obtain food by slashing it from side to side among schooling fish, stunning or killing them, then ingesting them whole. Juveniles also consume shrimp and crabs. The saws have sometimes been dried and sold as souvenirs. (Boschung et al. 1983; Robins and Ray 1986; Simpfendorfer 2005)
For more information about the biology and conservation of Smalltooth Sawfishes, visit the NMFS-NOAA, IUCN, and U.S. Fish & Wildlife Service pages devoted to this species.