SMALLER MAMMALS OF NORTH AMERICA 



57J 



perfectly organized machines for killing that 

 have been developed among mammals. Their 

 keen eyes are constantly alert to observe every- 

 thing about them, their ears are attuned to 

 catch the faintest squeak of a mouse or cry of 

 any other small animal, and their powers of 

 scent are very great. When hunting they dart 

 in and out of the holes of rodents, among 

 crevices in the rocks, or through brush piles, 

 pausing now and then to stand upright on their 

 hind feet, the head swaying to and fro as they 

 peer about. The squeak of a mouse starts 

 them instantly in search of it, and like a dog 

 they trail rabbits and other rodents by scent. 



As a rule, weasels are terrestrial, but in 

 wooded country they chmb trees and leap from 

 branch to branch with all the ease of squirrels. 

 In most localities they are not common, but 

 now and then, where conditions are peculiarly 

 favorable, they become numerous. At one 

 naturalist's camp in the upper Yukon they were 

 surprisingly abundant, so much so that more 

 than forty were caught in a few days in traps 

 set among broken rocks. There th;y were ex- 

 tremely bold, hunting for their prey among the 

 rocks within a few feet of the trappers. 



The prey of weasels includes almost every 

 kind of small rodent and bird living within 

 their territory. They feed especially upon 

 northern hares, cottontails, conies, ground 

 squirrels, chipmunks, tree squirrels, wood rats, 

 mice, lemmings, quail, ptarmigan, spruce and 

 ruffed grouse, ducks, and numberless other 

 small species. They are also very destructive 

 to domestic fowl, often killing thirty or forty 

 in a night. They unhesitatingly attack rodents 

 many times their own weight. 



Once when hunting on the open plain near the 

 southern end of the Mexican table-land, I saw 

 at some distance what appeared to be a brown 

 ball rolling about on the ground. This was 

 soon determined to be a weasel fastened to one 

 of the large and powerful pocket gophers of 

 that region. The weasel had its teeth set in the 

 back of the neck of the gopher, while the latter 

 was blindly trying to tear itself loose. I fired 

 an ineffectual shot at the weasel and it vanished 

 like a flash in the open tunnel of the gopher. 

 As I drew near, the gopher, still in fighting 

 mood, faced me with bared teeth. Later, when 

 I removed its skin, I found that the weasel had 

 torn loose the attachment of the heavy neck 

 muscles to the back of the skull until only a 

 thin layer remained to protect the spinal 

 column. This had been accomplished w'ithout 

 breaking the thin, but extremely tough, skin of 

 the gopher. 



When a weasel is attacking an animal which 

 resists, like a large ground squirrel, it raises 

 its head and sways its long neck back and 

 forth, its eyes glittering with excitement as it 

 watches for an opening to spring forward and 

 seize its prey. Its attack is always aimed at 

 a vital point, commonly tlie brain, the back of 

 the neck, or the jugular vein on the side. 



Weasels dig their own burrows under the 

 shelter of slide rock, ledges, stone walls, stumps, 

 and outbuildings, or they occupy hollow trees 



and the deserted burrows of other animals. In 

 nests thus safely located they have one litter 

 containing an average of from four to six, but 

 sometimes numbering up to twelve, young a 

 year. They are born at any time from April 

 to June, according to the latitude. The number 

 of young in a litter is enough to render weasels 

 very abundant, but this is rarely the case, and 

 raises the question as to the influence which 

 holds their number in check. 



They are both nocturnal and diurnal, ap- 

 parently in almost equal degree, since they are 

 frequently observed hunting in the middle of 

 the day, while their nocturnal raids on poultry 

 houses testify to their activities at night. When 

 hunting they appear like sinister shadows ..and 

 are persistent in pursuit. The young commoinly 

 remain with the female until nearly or /fjuite 

 grown and follow her closely on hunting trips. 

 It is interesting to see a pack of these deadly 

 carnivores working, the mother leading and the 

 young skirmishing on all sides, now spreading 

 out, now closing in. like a pack of miniature 

 hounds. On these family hunting parties, how- 

 ever, they usually keep close to the rocks, logs, 

 brush, or other cover. 



Themselves subject to the law of fang and 

 claw, weasels are killed and eaten by wolves, 

 coyotes, foxes, and various birds of prey. Their 

 very lack of fear perhaps in many cases leads 

 to their destruction. 



These representatives of the primitive wood- 

 land life continue to occupy practically all of 

 their original range. They visit farms in all 

 parts of the country and I have seen them near 

 the outskirts of Washington. 



It is well that weasels are not abundant, for 

 beasts with such innate ferocity and love of 

 killing would otherwise be a menace to the 

 existence of many useful species of birds and 

 mammals, especially the game birds. In many 

 places they live almost entirely on mice, and 

 there they should be left unmolested ;_ but 

 whenever they locate in the vicinity of a chicken 

 yard the owner will do well to take proper 

 measures for protection. 



THE LEAST WEASEL (Mustela rixosus 



and its relatives) 



{Por illustyation, see page 554) 



In addition to the larger members of the 

 tribe briefly described in the foregoing sketch, 

 the true weasels include another group of 

 species, so small they may appropriately be 

 termed the dwarfs of their kind. They vary 

 from a half to less than a fourth the size of 

 the larger weasels, but have the same char- 

 acteristic form and proportions, except that the 

 tail is very short and never tipped with black. 

 Like the larger species, they change their brown 

 summer coat for white at the beginning of 

 winter and back again in spring. 



The least weasels are also circumpolar m 

 distribution, but are limited to the northern 

 parts of Europe. Asia, and North America 

 In England and other parts of the Old World 



