2 8 Memoir Sears Foundation for Marine Research 



Pelvics about as long from origin to rear tip as interspace between dorsals; anterior 

 margins nearly straight; corners abrupt. 



Color. Nearly uniform dark mouse gray to blackish brown above, paler along 

 margins of fins. White to grayish white or pale yellow below. 



Size. The Common Sawfish is about two feet long at birth. It is known to reach 

 a length of about i8 feet, perhaps even more.''' Most of the individuals that wander 

 northward along the Atlantic Coast of the United States to North Carolina and beyond 

 are large. Thus the smallest of nine specimens taken on Cape Lookout Shoals was 

 12V2 feet long, while others as long as 16 feet, and none very small, have been re- 

 ported from estuarine waters of North Carolina. One taken off Ocean City, Maryland, 

 was 10 feet long; the two so far reported from New Jersey were 16 feet and 16 feet 



3 inches ; the most northerly record of all, from the vicinity of New York, was for one 

 of I 5 feet. A female of 1 5 feet has been found to contain embryos, but the size at which 

 they first breed is not known for either sex. One 12V2 feet long was reported as weighing 

 425 pounds; another of about 16 feet, 700 pounds. 



Developmental Stages. Embryos, so young that they still bear the large yolk sac, 

 already resemble their parents as regards relative position of fins and absence of lower 

 caudal lobe; however, the posterior edges of the dorsals do not assume their characteristic 

 concavity until near the time of birth. Their saws, like those of other embryonic Saw- 

 fishes, are soft and leathery previous to birth, and the rostral teeth are also soft and 

 entirely enclosed in the skin until birth, while a narrow band along each margin of the 

 saw is naked, both below and above. But the teeth attain their full size proportionate 

 to the size of the saw, and the margins of the latter become completely clothed with 

 denticles soon after the young are set free. Gravid females have been found with 15— 

 20 embryos. 



Habits. This species, like other Sawfishes, is almost exclusively restricted to the 

 immediate vicinity of the land and to water only a few feet deep. Indeed, we once had 

 the rather startling experience of striking a Sawfish of 12—14 feet with the bottom of 

 our boat when rowing in water only about three feet deep near Key West, Florida. And 

 we have seen another large one swimming there in water so shoal that its dorsal fins 

 were above the surface. It is most often encountered in partially enclosed waters, lying 

 in the deeper holes on bottoms of mud or muddy sand, and it frequents brackish water 

 as often as water of oceanic salinity. It has long been known to run up into fresh water 

 regularly, perhaps to remain there permanently, as in the lower reaches of the Amazon, 

 in the Essequibo in British Guiana, in the Atrato and San Juan rivers of Colombia 

 (tributary to the southwestern Caribbean), in the lower Mississippi, and in the St. Johns 

 River, Florida, which they are said to ascend to Jacksonville.*' On the other hand, 

 such specimens as wander northward in summer along the southeastern United States 



66. The maximum recorded length with which we are acquainted is i8 feet I'/j inches (vaguely rumored up to 20 ft.), 

 while specimens of 12-16 feet have been reported repeatedly. 



67. A landlocked population of this species may exist in Lake Nicaragua, where the existence of two kinds of Sawfishes 

 has been reported (Marden, Nat. geogr. Mag., 86, 1944: 184; and personal communication from Jose Arguillo 

 Gomez). 



