170 AGGREGATION, COMPETITION AND CYCLES 



or lest he waste his energy on a female that does not synchronize 

 with him." 



Territory among Mammals. Red squirrels arc thought by Hatt 

 (1929) to possess territories with a range of about 250 yards, within 

 which they seem to know every tree and hole. They have been seen 

 to drive off intruders, but the limits are evidently not fixed, since 

 they go beyond them for food. Mice of the genus Peromyscus may 

 have a home range about 100 yards in diameter, but P. maniculatus 

 artemisiae (Rho.), has been known to return over distances as great 

 as 5 miles. No dispersal of the young is definitely known, and many 

 individuals find suitable homes roundabout the original one. The 

 porcupine has also been assumed to establish territories with refer- 

 ence to food supply and den sites (Gabrielson, 1928), breeding, shelter, 

 and food all apparently being involved in the territorial coaction (cf. 

 Klugh, 1927; Murie and Murie, 1930). 



Among the mammals that feed in the sea and breed ashore, as 

 well as in certain sea birds, the selection and establishment of terri- 

 tories are often accompanied by intense competition and fierce com- 

 bats. In such instances food usually has little or no influence; thus, 

 the males of the fur seal do not feed during the period of control of 

 the harem territory, while the females may journey 50 to 100 miles to 

 gorge themselves with fish (Preble, 1923). Howard also notes that 

 in the guillemots the competition is necessarily for space in terms of 

 nesting sites and not of food (1920:215). 



Heape (1931:28) brought together a fund of information bearing 

 upon the territorial habits of mammals in particular, but much of this 

 is of the nature of general and often isolated observation, and in 

 consequence it possesses little significance. The treatment is far from 

 critical as attested by the statement that wolves respect the territory 

 of caribou when small game is abundant, but do not when the supply 

 of rabbits fails (page 46). In addition, the fable of the happy family 

 of rattlesnake, prairie dog, and burrow owl appears in a new form, in 

 which the voracious Sphenodon and petrel live together amicably in 

 the same burrow (page 47) . The inescapable tendency to broaden 

 the concept of territory in order to fit all the facts is shown by 

 Heape's distinction of a breeding or "home territory" ("almost invari- 

 ably recognized as a sanctuary, though not always respected"!), a 

 much wider "hunting territory," and a "neutral territory." Exclusive- 

 ness is not regarded as essential, and the term territory loses its justifi- 

 cation in all such cases (cf. Nice, 1933:91). 



Territory among Ants. Elton (1932) has outlined the territories 

 of wood ants [Forniica rufa) in a bird sanctuary in southern England. 



