Seasonal scatology of wolves along the Dempster Highway, northwestern Canada-an introduction of pollen analysis for dating old scats

This study aims to renovate the method of studying seasonal variation in wolf diet by introducing simultaneous analysis of undigested residua and pollen grains in wolf scats collected regardless of their freshness over a short period of time, in which pollen grains help to identify the season the diet was taken. The present study was conducted over a range of 500 km along the Dempster Highway extending north from Dawson, Yukon Territory to Inuvik, the Northwest Territories, Canada. We collected a total of 24 wolf scats along side roads and rivers, in which as many as 14 million pollen grains/scat were found on an average. The analysis revealed that the wolves relied exclusively on the caribou during winter when scats are free of pollen grains, but increase their dependence on the beaver and other mammals up to over 50% in term of residuum occurrence in spring and summer when scats are respectively loaded primarily with arboreal and herbaceous pollen grains. This result was consistent with the local fauna of prey animals, the migration pattern of the caribou for breeding and wintering, availability of the beaver and other rodents as dictated by ice/snow cover, and breeding and cub rearing pattern of the wolves themselves. Thus it was concluded that the pollen analysis serves as a powerful and effective tool for identifying the seasonality of old scats, and therefore saves a great deal of time and effort to be devoted to finding fresh scats

Forest cover classification using Landsat Thematic Mapper data for areal expansion of line LAI estimate generated through airborne laser profiler

A simple cover classification of Canadian boreal forest was conducted using Landsat Thematic Mapper (TM) imagery to expand a line estimate of leaf area index (LAI) into a two-dimensional regional one. The line estimate had been made through a 600km long continuous vegetation profile obtained by airborne laser altimetry. The present study area of 170×30km straddles the central portion of the laser profiling transect, from Wandering River north to Fort McMurray, Alberta, Canada. A total of eight land cover types were identified first in the field, and then some 83 training points and another 74 reference points were chosen and recorded for a supervised classification and its accuracy assessment respectively. By applying a supervised procedure to Landsat TM data in two different seasons, these eight cover types, consisting of six vegetated covers, i. e. closed and open conifer forests, conifer woodland, closed and open broad-leaved forests and marsh thicket, and two nonvegetated covers, i. e. bare ground and water surface, were classified. The classification was basically successful with an overall accuracy of 76%. Finally, using an overlay of this land cover map and the airborne laser profiling flight track, the mean LAI for each type of vegetation cover was obtained, and subsequently fed back to the land cover map to form a false-color map showing the two-dimensional distribution of LAI over the entire study area