1 24 ECONOMIC MAMMALOGY 



and mollusks and devote their attention for a time to fish. One hump- 

 backed whale contained about a ton of sardines, with some smelt and 

 anchovies, and a sperm whale contained a ten-foot shark. 1 As a gen- 

 eral rule, fishes taken by whales are of small, abundant species, whose 

 commercial value is not very high. We have not happened upon very 

 definite information concerning the food habits of other cetaceans, 

 though probably it exists somewhere in the much-scattered literature 

 of mammalogy. Various writers do say in a very general way that 

 the porpoises and dolphins feed chiefly upon fish, though the Risso 

 dolphin is said probably to subsist upon squid and cuttlefish. 2 Porpoises 

 may often be seen following ships and eating the waste food thrown 

 overboard. 



Several species of fur-bearers (Mustelidae) are very fond of fish 

 and enter water after them, and fish is extensively and successfully 

 used for bait by trappers. The land otter is said to live chiefly upon 

 fish, but also to take frogs, etc. 3 Coues says that the sea otter un- 

 doubtedly eats fish, though its diet is chiefly mollusks and sea-urchins. 4 

 The mink is very fond of fish and haunts the banks of streams and 

 lakes, taking also reptiles and amphibians, with other food. 5 The diet 

 of the pine marten is similar to that of the mink, but the Pennant 

 marten, or "fisher," notwithstanding its name, does not habitually 

 fish, though it takes fish as bait in traps. 6 



Raccoons and muskrats are known to sometimes eat fish and frogs, 

 and the latter also eat caddis larvae and other food of fishes, thus to 

 a slight degree affecting the fish fauna, 7 La Valette mentions the 

 aquatic shrew, weasel, polecat, domestic cat, otter and bear as enemies 

 of fish. 8 Haack says that shrew-mice ("wasserspitzmausen") in brooks 

 are "well-known enemies of fish/' 9 



1 Evermann, Scientific Monthly, xv, 309-310, 1922. 



2 Aflalo, Nature Lovers' Library, v, 299, 1917; Standard natural history, n, 335, 

 1908. Hornaday, American natural history, n, 154, 1914. Stone and Cram, American 

 animals, p. 21, 1902. 



3 Merriam, N. Amer. Fauna, No. 5, p. 82, 1891. Bailey, N. Amer. Fauna, No. 49, 

 p. 179, 1912. Audubon, as quoted by Coues, N. Amer. Mustelidae, p. 315, 1877. 



4 Coues, N. Amer. Mustelidae, p. 345, 1877. 



8 Howell, N. Amer. Fauna, No. 45, p. 37, 1921. Bailey, N. Amer. Fauna, No. 49, 

 p. 173, 1926. Ashbrook, Mink raising, U. S. Biol. Surv. Leaflet No. 8, 1928. 



8 Coues, N. Amer. Mustelidae, pp. 66-68, 92, 1877. Bailey, N. Amer. Fauna, No. 

 49, P- 177, 1926. 



7 Lantz, The muskrat, U. S. Biol. Surv. Bull. No. 396, p. 21, 1910. Annin, Car- 

 penter, Elliott and Hessel. Bull. U. S. Bureau of Fisheries, iv, 85-86, 295-298, 4/0, 

 579-584, 1884. Sturr, Bull Bur. Fish., v, 342, 1885. Johnson, Roosevelt Wild Life Bull, 

 m, 247, 1925. Howell, N. Amer. Fauna, No. 45, p. 35, 1921. Bailey, N. Amer. Fauna, 

 No. 49, p. 187, 1926. 



8 La Valette, The enemies of fish, Kept. U. S. Fish Comm. for 1878, pp. 509-516. 

 ' Haack, Bull. U. S. Fish Comm., iv, 375-376, 1884. 



