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Crown survey notes from the late 1800s were used to reconstruct forest cover at that time in four forest management units in central Ontario, Canada. Historic forest cover was then compared to forest cover in 1990 based on Forest Resources Inventory (FRI) maps. Regional results indicate that the proportions of maple (Acer spp.) in the forest increased by 12.5%, while balsam fir (Abies balsamea) declined by 3.5%, hemlock (Tsuga canadensis) by 2.3% and other conifers (larch (Larix laricina) and cedar (Thuja occidentalis)) by 2.1%. The frequency of occurrence of maple, ash (Fraxinus spp.), yellow birch (Betula alleghaniensis), poplar (Populus spp.) and spruce (Picea spp.) also increased while white birch (Betula papyrifera), hemlock and other hardwoods (e.g., oak (Quercus spp.), basswood (Tilia americana), beech (Fagus grandifolia), elm (Ulmus spp.), ironwood (Ostrya virginiana) and black cherry (Prunus serotina Ehrh.)) declined. The region-wide proportional increase in maple is likely due to timber harvest techniques such as selective logging, effective fire suppression and the ecology of the maple species. Crown survey notes have been a useful tool in reconstructing presettlement forest cover. Survey notes can easily be obtained and used by forest managers and planners to understand presettlement conditions of this forest. Managers can achieve zero net loss of forest types in relation to the presettlement condition by using appropriate silvicultural practices to reduce the proportion of maple.Key words: Crown Survey records, presettlement forest, Great Lakes-St. Lawrence Forest, working group, frequency of occurrence Les relevés d'arpentage des terres publiques de la fin des années 1800 ont été utilisés pour reconstituer le couvert forestier de l'époque dans quatre unités d'aménagement forestier du centre de l'Ontario au Canada. Le couvert forestier de cette époque a été comparé par la suite au couvert forestier de 1990 en fonction des cartes de l'Inventaire des ressources forestières. Les résultats régionaux indiquent que la proportion d'érable (Acer spp.) dans les forêts a augmenté de 12,5 % tandis que le sapin baumier (Abies balsamea) a diminué de 3,5 %, la pruche (Tsuga canadensis) de 2,3 % et les autres conifères (le mélèze (Larix laricina) et le thuya (Thuja occidentalis)) de 2,1 %. La fréquence de la présence de l'érable, du frêne (Fraxinus spp.), du bouleau jaune (Betula alleghaniensis), du peuplier (Populus spp.) et de l'épinette (Picea spp.) a également augmenté tandis que le bouleau blanc (Betula papyrifera), la pruche et les autres bois francs (par ex., le chêne (Quercus spp.), le tilleul (Tilia americana), le hêtre (Fagus grandifolia), l'orme (Ulmus spp.), l'ostryer (Ostrya virginiana) et le cerisier tardif (Prunus serotina Ehrh.)) ont décliné. L'accroissement proportionnel dans toute la région pour l'érable est vraisemblablement dû aux techniques de récolte telle la coupe sélective, à la suppression totale des feux de forêt et à l'écolo-gie des érables. Les relevés d'arpentage des terres publiques o...

We examined the hypothesis that female spruce grouse (Dendragapus canadensis) rely entirely on their spring diet or endogenous reserves for the nutrients required for clutch formation. Spring food habits of 40 radio-tagged hens were documented by direct observation (21 262 min) during the period encompassing oviducal recrudescence, follicular development, and egg laying (late April – late May 1984 – 1986) and compared with clutch size and mean egg weight. Hens consumed conifer foliage, flowers, fruits, and foliage of ground plants, grit, and arthropods. Compared with their prebreeding diet, foods preferred in spring were rich in protein and P, but not necessarily Ca. Large clutch size was associated with a high rate of intake of the two most preferred foods, flowers of trailing arbutus (Epigaea repens) and spore capsules of Polytrichum mosses, and crude protein, P, and Ca, but was not related to the size of hens (body weight) or the size of endogenous reserves (scaled body weight). Egg size was not associated with spring diet or the size of endogenous reserves, but appeared to be related to the size of hens. Rate of intake of arbutus flowers and moss capsules was correlated with their availability on territories, suggesting that clutch size might have been proximately limited by food supply. However, rough estimates of nutrient intake suggested that the spring diet provided only about 60% of the protein and 45% of the Ca needed for clutch formation. Consequently, hens appeared to rely on both their spring diet and stored reserves for the nutrients required for clutch formation.

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We used instrumental neutron-activation analysis to determine the concentrations of Br, Mn, Cl, Al, and Na in primary feathers 1, 9, and 10 of Spruce Grouse (Dendragapus canadensis) in four jack pine (Pinus banksiana) forests in northern Ontario. Our objective was to see if there were consistent trends in intrapopulation variation of mineral profiles among populations. Except in the case of Na concentration, there were significant sources of variation attributable to age (adult versus chick) and sex in all forests, and there were large differences among study sites. Yearling and adult grouse that recruited to the breeding population differed in the elemental composition of their feathers from long-term residents of the same age. Information on intrapopulation variation, which traditionally has confounded studies of geographic variation, may have useful applications in research and management. If trends are repeatable and predictable, feather profiles may be used to identify the age or sex of a bird and the origin of recruits on a microgeographic scale.