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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



and that the two groups do not mingle. In view 

 of the well-known wandering habits of manatees, 

 especially in summer, this assumption seems quite 

 improbable. Allen (1942) reviewed the case and 

 said Hatt (1934) considered the two as racially 

 distinct. Moore (1951) has shown that certain 

 skull characters (indices of the foramen magnum) 

 of a small series of specimens from Texas, 

 Louisiana, and Florida did not show differ- 

 ences. The Texas specimens would presumably 

 belong to the West Indian race, according to the 

 summary of distribution given by Allen (op. cit.). 

 Whether or not the small anatomical differences 

 would stand up if a larger series were studied 

 remains to be seen. In the meantime, it seems 

 preferable to refer to the Floridian, West Indian, 

 and northern South American manatees as one 

 group. 



The present and recent past distribution of T. 

 manatus is from south central and southern 

 Florida, through the West Indies and Antilles to 

 Mexico, and southward throughout Middle Amer- 

 ica to British Guiana. There they seem to stop 

 and do not overlap the range of T. inunguis, an 

 inland species of the Amazon and adjacent regions. 

 Northward, manatees extend up the coast of 

 Mexico to Veracruz. This may be said to be the 

 winter range for some manatees are wanderers in 

 summer. They have been reported in the litera- 

 ture from the Carolinas and Virginia. Popular 

 writings on natural history and newspaper ac- 

 counts indicate, without much doubt, that they 

 occasionally reach the coast of New Jersey. 

 True (1884) mentioned the probable case of a 

 manatee which was washed ashore dead on the 

 Shetland Islands in 1785 and said it must have 

 "set sail" from the Florida coast. 



True quotes Silas vStearas on reports that 

 manatees were formerly occasionally seen on the 

 northern Gulf coast from Pensacola to New Or- 

 leans, and that their bones were formerly common. 

 Gunter (1941) reported a skull from Louisiana 

 and several specimens from Texas. True (op. 

 cit.) said a South American manatee was taken 

 in Texas in 1855. Formerly manatees visited the 

 mouth of the Rio Grande every summer, coming 

 from farther south in Mexico. At least three were 

 captured alive there in 1911 and 1912 and were 

 later exhibited over the country. They have been 

 unreported for the past 10 years, probably because 

 of population decline. In former times it is 



probable that manatees visited all coasts of the 

 Gulf of Mexico in summer, although less abun- 

 dantly to the north. 



Manatees are extremely sensitive to cold, as 

 has beea reported many times, and are sometimes 

 killed by cool weather as far south as the Florida 

 Keys. It is most improbable that they lived the 

 year-round on the northern Gulf coast, and they are 

 continuous residents in the United States only in 

 Florida. In the days when manatee populations 

 were much more extensive, possibly they did 

 leave bones in numbers along the northern Gulf 

 coast, as stated by Stearns, and these may have 

 been the result of early cold waves or winter kills. 

 Moore (1953) has shown that manatees live 

 quite far inland along some of the rivers of 

 northern Florida and do not go south during the 

 winter. Instead they move to the vicinity of 

 large springs during cold speUs where the water 

 temperatiu-e never falls below 70° F. 



Manatees, along with other sirenians, have the 

 heaviest bone structure known, and the long bones 

 are like ivory. They have paddle-like forelimbs 

 and no hind limbs. They are pure vegetarians 

 and inhabit coastal waters where their food grows. 

 They are found occasionally in the open sea, near 

 the shore. The upper lip is more or less cleft and 

 the two halves can be manipulated independently. 

 The Sirenia have no close relatives but seem to 

 have distant affinity with the elephants. There 

 are similarities of the skull, and these two groups 

 alone among mammals have teeth which grow 

 forward along the jaw to replace those which are 

 worn away. Manatees are lethargic animals and 

 can remain under water 12 minutes. Little is 

 known about them and they should be carefully 

 studied in their native haunts. According to 

 Moore (1953) young Florida manatees have been 

 reported for every month except December. 



The late Capt. C. M. Scammon was noted as 

 a chronicler of marine mammals wherever he 

 went. In describing the general habits and ap- 

 pearance of manatees we can do no better than 

 to quote his words (in part) from an unpublished 

 manuscript: ' 



The Sea-Cows may be regarded as among the most 

 interesting creatures in their habits and disposition of all ■' 

 the marine mammals. Yet in respect to their form and 

 general appearance, they seem like animals of a low order. 



' Unpublished manusCTipt loaned by Joel W. Hedgpeth. 



