Summer above-ground movements of Northern Pocket Gophers, Thomomys talpoides, in an alfalfa field

Abstract

Northern Pocket Gophers' (Thomomys talpoides) above-ground movements were studied with a fluorescent U.V. powder spread over 10 to 18 burrow systems from 1 June to 8 September 1993 in an alfalfa field near Vegreville, Alberta. Gophers did not limit their surface activities to burrow openings. The number of burrow systems with above-ground movements over a 48-h period decreased from June (90%) to July (50%), August (17%), and September (0%). Gophers exiting their burrow system produced trails with an average length of 28.7 (SE = 2.4) cm in June, 16.8 (+- 4.1) cm in July, and 23.0 (+- 5.7) cm in August. The mean sums of trail lengths per burrow system were significantly greater (P lt 0.05) in June (130.8 +- 32.6 cm) than in July (43.6 +- 16.5 cm) and August (46.0 +- 12.0 cm). In late summer, surface movements were almost nonexistent. The number and extent of gophers' above-ground movements may be related to the presence of vegetative cover and a gradual change in feeding behavior over summer.