ABSTRACT. Historical data sources on the bowhead whale ( B a l a m mysticetus) provide the means to statistically examine the relationships of body and baleen size and oil yield. These data demonstrate a linear relationship between length of the whale and baleen length, with no apparent differences between males and females. Since baleen length wasa standard measure of size, it is possible to compare sizes of whales taken on different whaling grounds with the sizes of living whales today. A quadratic regression provides the best fit for baleen length versus oil yield, but a linear regression is best for baleen weight versus oil yield. Commercial oil return may be useful in examining the evolution of the whaling industry and aspects of population segregation of the bowhead.Key words: bowhead whale, Balaena mysticetus, Baffin Bay -Davis Strait, whaling, morphometry, oil yield RÉSUMB. Des données historiques sur la baleine franche (Balaena mysticetus) fournissent un moyen pour étudier statistiquement le rapport entre la taille du corps et des fanons et la quantité d'huile. Ces données démontrent une relation linéaire entre la longueur de la baleine et la longueur des fanons, les différences entre mâles et femelles étant apparemment nulles. Vu que la longueur des fanons était une mesure standard de 1 taille, il est possible de comparer la taille de baleines pêchées A des emplacements différents avec la taille de baleines vivant actuellement. Une régression quadrative donne la meilleure relation entre la longueur de la baleine et la quantitéd'huile, mais une régression linéaire représente mieux le rapport entre le poids de la baleine et la quantité d'huile. Les bénéfices commerciaux de l'huile peuvent être utiles dans l'étude de l'évolution de l'industrie baleinière et de certains aspects de la ségrégation de la population des baleines franches. Large as the size of the whale certainly is, it has been much over-rated; for such is the avidity with which the human mind receives communications of the marvellous, and such the interest attached to those researches which describe any remote and extraordinary production of nature, that the judgment of the traveller receives a bias, which, in cases of doubt, induces him to fix upon that extreme point in his opinion which is calculated to afford the greatest surprise and interest.. . . When the animal inhabits an element where he cannot examine it, or is seen under any circumstances which prevent the possibility of his determining its dimensions, his decision will certainly be in that extreme which excites the most interest. Thus a mistake in the size of the whale could easily be made.

To assess genetic diversity in the blue-listed purple martin (Progne subis) population in British Columbia, we analysed mitochondrial control region sequences of 93 individuals from British Columbia and 121 individuals collected from seven localities of the western and eastern North American subspecies P. s. arboricola and P. s. subis, respectively. Of the 47 haplotypes we detected, 34 were found exclusively in western populations, and 12 were found only in eastern populations. The most common eastern haplotype (25) was also found in three nestlings in British Columbia and one in Washington. Another British Columbia nestling had a haplotype (35) that differed by a C to T transition from haplotype 25. Coalescent analysis indicated that these five nestlings are probably descendents of recent immigrants dispersing from east to the west, because populations were estimated to have diverged about 200,000-400,000 ybp, making ancestral polymorphism a less likely explanation. Maximum likelihood estimates of gene flow among all populations detected asymmetrical gene flow into British Columbia not only of rare migrants from the eastern subspecies in Alberta but also a substantial number of migrants from the adjacent Washington population, and progressively lower numbers from Oregon in an isolation-by distance pattern. The influx of migrants from different populations is consistent with the migrant-pool model of recolonization which has maintained high genetic diversity in the small recovering population in British Columbia. Thus, the risk to this population is not from genetic erosion or inbreeding following a severe population crash, but from demographic stochasticity and extinction in small populations.

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Artificial pruning can increase the quantity of high-value L'Clagage artificiel peut accroitre la quantitC rCcoltCe de clear lumber harvested from Douglas-fir, but the pruning cost bois de sciage de sapin de Douglas en qualit6 et en prix, mais per tree is relatively high. To prune a young Douglas-fir to 6 les coiits d'Clagage par arbre sont ClevCs. L'Clagage d'un jeune metres in one lift and two lifts took, respectively, 9.5 and 10.1 sapin de Douglas jusqu'i 6 mBtres de hauteur en une seule et minutes in 14-and 18-year old stands with average spacing en deux Ctapes nCcessite, respectivement, 9.5 et 10.1 minutes between trees of about 3 metres on flat or 0-30% south-facing dans des peuplements de 14 i 18 ans dont l'espacement slopes in coastal British Columbia. The associated costs were moyen entre les arbres est d'environ 3 mBtres sur un terrain $2.09 and $2.22. This included minor travel time between plat ou ayant une pente de 0-30% orientCe vers le sud dans la trees, but excluded the cost of travelling to the site, selecting rCgion c6tiBre de la Colombie-Britannique. Les coiits associCs and marking trees to be pruned, and purchasing and maintain-