. The Canadian field-naturalist. 1977 Notes 73 Vegetation type Pe rcent cover â¢â â¢" Moss & Lichen 16 0 t 18 45 *;â Grass & Sedge W Shrub 34 17 38 2 2 t 0 t 5 8 17 6 64 5 49 ' " Litter 47 97 76 48 45 Exposed soil 23 0 3 18 0. 70 CUTTINGS 6U 39 50 40 41 30 30 20 18 10 15 4 1 ,2,0 1 0 80i BURROWS 70 31 60 50 44 40 30 70 r^O 16 8 10 13 0 2 1 6 40-| RUNS 30 81 37 rrrl^M 68 30 n 57 19 10 15 15 73 74 73 74 73 74 73 74 73 74 E Jge o f Wat er Mid-E each B ase c f Bar k Mid- Bank 1 rop oi Bank Figure 1. Distribution of chestnut-cheeked vole "sign" during 1973 and 1974 in re
. The Canadian field-naturalist. 1977 Notes 73 Vegetation type Pe rcent cover â¢â â¢" Moss & Lichen 16 0 t 18 45 *;â Grass & Sedge W Shrub 34 17 38 2 2 t 0 t 5 8 17 6 64 5 49 ' " Litter 47 97 76 48 45 Exposed soil 23 0 3 18 0. 70 CUTTINGS 6U 39 50 40 41 30 30 20 18 10 15 4 1 ,2,0 1 0 80i BURROWS 70 31 60 50 44 40 30 70 r^O 16 8 10 13 0 2 1 6 40-| RUNS 30 81 37 rrrl^M 68 30 n 57 19 10 15 15 73 74 73 74 73 74 73 74 73 74 E Jge o f Wat er Mid-E each B ase c f Bar k Mid- Bank 1 rop oi Bank Figure 1. Distribution of chestnut-cheeked vole "sign" during 1973 and 1974 in relation to vegetation and microtopography on the margin of a small lake located in the Northwest Territories. The 't' represents cover values less than 1%. Numbers in the barsrepresent the number of observations. The diagram is schematic, drawn to approximate scale, and represents only an average cross section of the beach. cover during cutting activities. Most burrows were concentrated along the base of the bank (Figure 1). Few burrows were found higher up the bank and even fewer on the beach. The base of the bank had a dense cover of graminoids and litter, and was at a point where both the water table and active layer (that layer of soil that thaws during the summer but is underlain by permafrost) were deep enough to allow burrowing. Thus the burrows were located as close to food and cover as burrowing conditions would allow. Even though graminoids were densest near the burrows, most cuttings were found closer to the water. Either the voles did less foraging near their burrows or they removed the cuttings close to the burrows more often than the distant cuttings. Of the three types of sign, runs were the most evenly distributed in relation to the beach and bank but, like. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble t
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