The following frequency index is compiled from the foregoing data on prey of _Mustela frenata_.
Moles (family _Talpidae_), 5 Shrews (family _Soricidae_), 26 Pigmy weasel (_Mustela rixosa_), 1 Ground squirrels (genus _Citellus_), 23 Chipmunks (genus _Tamias_), 38 Tree squirrel (possibly all _Tamiasciurus_), 8 Flying squirrel (genus _Glaucomys_), 1 Pocket gophers (family _Geomyidae_), 34 Mice (order _Rodentia_), 96 Harvest mice (genus _Reithrodontomys_), 36 Grasshopper mouse (genus _Onychomys_), 1 Deer mice (genus _Peromyscus_), 235 Cotton rat (genus _Sigmodon_), 2 Wood rats (genus _Neotoma_), 14 Meadow mice (genus _Microtus_), 248 Muskrat (genus _Ondatra_), 1 Old World rats (genus _Rattus_), 19 House mouse (genus _Mus_), 1 Jumping mouse (genus _Zapus_), 5 Varying hare (_Lepus americanus_), 5 Rabbits (genus _Sylvilagus_), 48 small birds, 32 chickens, 17 lizard, 1 snakes, 4 insects, 3
More significant than the above compilation, of course, are the results of careful studies of the food of the long-tailed weasel in restricted areas. Examples of such studies are those of Polderboer, Kuhn and Hendrickson (1941) and Hamilton (1933:333).
According to Hamilton's (1933:332) observations on captive weasels, "There seems to be little relative difference in the amount they eat, regardless of their activities.
"In general, more food is taken in summer than in winter. Usually about a third their weight every 24 hours is eaten, but a growing young weasel will consume much more. A young male _noveboracensis_, weighing 145 grams, consumed an entire chipmunk, fur and bones, weighing 85 grams, in 24 hours. A day later it ate all of a partly grown rat, 105 grams, in the same length of time."
Moore (1945:253) records that a captive male that he obtained at Gainesville, Florida, consumed, on the average, between 63 and 70 grams of flesh and blood per day. The weasel itself weighed approximately 320 grams.
Sanderson (1949:413), concerning seven young weasels from Manitoba, that he raised in captivity, writes: "From the fifth to the seventh week of age, they consumed approximately 22 per cent of their body weight per day; from the eighth to the tenth week (just before reaching mature size) they consumed approximately 24 per cent; but after reaching maturity they consumed only 18 per cent. When given all the food they would take in one day, they ate as much as 40 per cent of their body weight."