SMALLER MAMMALS OF NORTH AMERICA 



479 



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ARMED NDUTRAI^ITY : A DOG AND A SKUNK PREPARE FOR COMBAT 



Once in a lifetime the photographer of wild Hfe gets an opportunity such as is recorded 

 here. Luck was with the camera man, but not with the terrier, as a moment after this picture 

 was made the dog was a very nauseated and embarrassed animal, the skunk having employed 

 its natural weapon with overpowering odoriferous effect. 



GOOD HOUSEKEEPING IN RODENT LAND 



One can but marvel at the wise pre- 

 science with which northern rodents 

 gather their winter stores and hide them 

 away safe from the weather in secret 

 places in hollow trees, old logs, crevices 

 among the rocks, or in neat storage cham- 

 bers dug for the purpose adjoining under- 

 ground burrows. The size of the stores 

 and the tireless industry of these little 

 husbandmen in gathering them might 

 well serve as examples worthy of emula- 

 tion by some of their human neighbors. 

 The seeds gathered are freed from chaff, 

 the grasses and herbs are dried as "hay," 

 and roots are carefully cleaned before 

 being stored. 



The storing habit appears to be nearly 

 alwa3^s for purely individual benefit. The 

 food is usually stored in bulk, but squir- 

 rels and chipmunks often bury liere and 

 there single nuts, which they are able to 

 recover long afterward through their ex- 

 traordinary powers of smell. 



Stores are laid by for a single season, 

 and a single faihire of a nut or seed crop 

 will cause the starvation of many small 

 animals, and the failure of the crops for 



two or more seasons is so disastrous that 

 the rodents may nearly or quite all die of 

 famine over great areas. The reverse of 

 this occurs during successive years of 

 bountiful nut and seed crops. 



An abundant food supply appears to 

 be a powerful stimulant to the fecundity 

 of mammals, and the number of young 

 at a birth, as well as the number of litters 

 born during a season, are greatly in- 

 creased by it, until their haiuits fairly 

 swarm with them. 



THE EBB AND ELOW OF ANTAGONISTIC 

 SPECIES 



With this stimulated increase of rodent 

 life goes a related increase in the number 

 of birds and mammals which prey upon 

 them. The close relationship between 

 the numbers of rodents and of the car- 

 nivores which prey upon them is shown 

 by the records of the Hudson Bay Com- 

 pany, in which with the increase or de- 

 crease in the abvmdance of varying-hare 

 skins secured by the fur traders goes a 

 corresponding increase or decrease in the 

 number of lynx skins taken. 



After rodents become cnorniouslv 



