Site Variation in Summer Foods of Arctic Fox, Prince of Wales Island, Northwest Territories

Abstract

Analysis of 840 arctic fox (Alopex lagopus) feces (scats) from Prince of Wales Island, indicate that collared lemming (Dicrostonyx groenlandicus) are the most frequent food item. Caribou (Rangifer), arctic hare (Lepus arcticus) and ermine Mustela erminea) were less important. Bird remains were not prevalent in the arctic fox scats. A marked difference was found between prey items at a den site and those recovered in scats from general searches. Caribou remains were more prevalent in scats from a den site because adult foxes were scavenging nearby wolf kills. Arctic fox scats were collected on Prince of Wales Island, Northwest Territories during July and August 1977 at a den site (n=375) and on general searches (n=465) surrounding the den. The Russell River den site (73 41' N, 97 41' W) is situated 100 m from an unnamed river, approximately 5.0 km from the northeast coast of the island. The den site is a low ( area in the northeastern region of the island between Bellot Cliff (73 32' N, 97 41' W) and Back Bay. These areas completely surround the den site and were an adequate scat sample for other arctic foxes travelling the general vicinity of the den site. All scats were collected separately and labelled with location. Winter scats were easily discerned from summer scats by their leeched appearance and by the apparent age of the scat deposition site. Only scats considered to be from the summer of 1977 were used in the analysis. Adult and whelp scats were separated following the criteria presented by Speller (1972). On general searches, scats were collected at a distance from the den to avoid overlap between den scats and those found elsewhere. Analysis of the scats was done on the basis of the microstructure of the hair or feathers recovered. After the scats were washed through 2 sieves (mesh size 75 and 200pm), the hair remains were mounted on acetate strips and examined microscopically (Williamson, 1951). A reference collection of known hair samples of all possible prey species available to arctic fox on Prince of Wales was used to identify hair. Feather remains were identified to taxonomic order after the methods outlined by Day (1966). All species identified from the scats were listed and these data were analysed by frequency of occurrence of items in the total numbers of scats. A Chi-square test of independence was used to find the significance of the variation in food items from each site.