Spatial distribution of the larval populations of 6 snow-melt mosquito species for several vast string bogs of the High-subarctic area of Lake Delorme, Quebec (55 00'N; 69 58'W) was analyzed using a reciprocal averaging (RA) analysis and a cluster analysis. Results of these analyses indicate that the vegetation of the bog ridges may be a useful indicator of the environmental features. Aedes excrucians and Ae. riparius are highly correlated with the Carex rostrata vegetal unit; Ae. hexodontus and Ae. decticus with the Carex limosa unit; Ae. canadensis with the Chamaedaphne calyculata unit and Ae. punctor with the Picea mariana and Carex oligosperma units. The RA analysis also indicates that the mosquito larval community of shallow water-filled hollows is more related to the ridge vegetation unit giving a general physiognomy to the habitat rather than the size or vegetation of the shallow pool itself. Results are discussed taking in account the high potential selectivity shown by the females for their oviposition sites.