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The initiatives of Ligeex, a Tsimshian chief, shows the complexity and sophistication of the indigenous geopolitical systems on the North-West Coast. According to Euro-American materials, trade on North West coast involved geopolitics and contests for trade and control of territory. The indigenous people who provided furs owned territories, and they had to face the manifold economic changes affecting their tribes, regions and nations. Ligeex tried to bring back stability and involve more people.

Analysis of nominal census of British Columbia for 1851 reveals the population structure and distribution in the province. The white, Chinese and Indian populations lived in separate areas and did not identify common class interests. The period was marked by the whites' reconceptualization that fixed on their whiteness and abstracted from their ethnicity. The patterns resemble those found in the American west coast, New Zealand and Australia.

The article discusses the exploitation of gold deposits on Haida Gwaii, British Columbia and how the gold rush brought about an interaction between the prospectors who wanted to exploit the resources and the native Haida people. Topics include the competition between the fur trading company the Hudson's Bay Company and American settlers to find gold in Haida Gwaii, and how the Haida allegedly viewed the prospectors as an opportunity to improve trade opportunities.

Understanding the mechanisms that drive prey selection is a major challenge in foraging ecology. Most studies of foraging strategies have focused on behavioural costs, and have generally failed to recognize that differences in the quality of prey may be as important to predators as the costs of acquisition. Here, we tested whether there is a relationship between the quality of diets (kJ ⋅ g-1) consumed by cetaceans in the North Atlantic and their metabolic costs of living as estimated by indicators of muscle performance (mitochondrial density, n = 60, and lipid content, n = 37). We found that the cost of living of 11 cetacean species is tightly coupled with the quality of prey they consume. This relationship between diet quality and cost of living appears to be independent of phylogeny and body size, and runs counter to predictions that stem from the well-known scaling relationships between mass and metabolic rates. Our finding suggests that the quality of prey rather than the sheer quantity of food is a major determinant of foraging strategies employed by predators to meet their specific energy requirements. This predator-specific dependence on food quality appears to reflect the evolution of ecological strategies at a species level, and has implications for risk assessment associated with the consequences of changing the quality and quantities of prey available to top predators in marine ecosystems. [ABSTRACT FROM AUTHOR]

Food sources for cultivated marine bivalves generally are not well identified, although they are essential for a better understanding of coastal ecosystems and for the sustainability of shellfish farming activities. In addition to phytoplankton, other organic matter sources (OMS), such as microphytobenthos and detritus (of terrestrial or marine origins), can contribute significantly to the growth of marine bivalves. The aim of this study was to identify the potential food sources and to estimate their contributions to the growth of the Pacific oyster ( Crassostrea gigas) in two contrasting trophic environments of Normandy (France): the Baie des Veys (BDV) and the Lingreville area (LIN). Two sites were studied in the BDV area (BDV-S and BDV-N) and one in the LIN area. To estimate the contribution of each type of OMS, we used a combination of stable natural isotope composition (δ13C, δ15N) analysis of OMS and oyster tissue together with a modelling exercise. Field sampling was conducted every 2 months over 1 year. The sampled sources were suspended particulate organic matter from marine (PhyOM) and terrestrial (TOM) origins, microphytobenthos (MPB), detrital organic matter from the superficial sediment (SOM), and macroalgae ( Ulva sp., ULV). A statistical mixing model coupled to a bioenergetic model was used to calculate the contributions of each different source at different seasons. Results showed that isotopic composition of the animal flesh varied with respect to the potential OMS over the year within each ecosystem. Significant differences were also observed among the three locations. For instance, the δ13C and δ15N values of the oysters ranged from −20.0 to −19.1‰ and from 6.9 to 10.8‰ at BDV-S, from −19.4 to −18.1‰ and from 6.4 to 10.0‰ at BDV-N, and from −21.8 to −19.4‰ and from 6.3 to 8.3‰ at LIN. The contributions of the different sources to oyster growth differed depending on the ecosystem and on the period of the year. Phytoplankton (PhyOM) predominated as the principal food source for oysters (particularly in the LIN location). MPB, TOM, and ULV detritus also possibly contributed to oysters’ diet during summer and autumn at the BDV-S and BDV-N sites. SOM was not considered an OMS because it was already a mix of the other four OMS, but rather a trophic reservoir that potentially mirrored the trophic functioning of marine ecosystems. [ABSTRACT FROM AUTHOR]

La question du rôle de la privation de nourriture dans la mortalité des premiers stades larvaires des poissons marins dans leur milieu naturel a suscité d'importants travaux. Les méthodes proposées font appel à différentes techniques dont aucune n'a jusqu'alors réuni tous les avantages recherchés. Le rapport ARN/ADN, prôné par de nombreux auteurs, semble présenter une variabilité qui nuit à l'efficacité de son application in situ. Quelques arguments conceptuels simples conduisent à proposer un nouvel indice biochimique, la teneur de la larve en ADN, exprimee en μg/mg de poids sec (ADN/PS). Plusieurs élevages expérimentaux de larves de sole (Solea solea L.) ont été entrepris pour tester cette approche: des privations totales ou différées de nourriture leur ont été infligees à deux températures. Il est tout d'abord vérifié que l'évolution du rapport ARN/ADN au cours du développement ontogénique d'individus témoins nourris montre une forte variabilité qui, de plus, n'est pas reproductible, pour un même stade de développement, d'un élevage à l'autre, pourtant menés dans des conditions standard rigoureusement identiques. A I'inverse, ADN/PS s'av ère beaucoup plus stable chez les témoins et présente essentiellement deux niveaux, identiques pour les deux températures testées et caractéristiques respectivement de la larve à symétrie bilatérale, puis de l'animal en cours de métamorphose pleuronecte. L'effet de la privation de nourriture est tr ès marqué chez les premiers stades, caractérisé par une élévation rapide, nettement au-del à du seuil significatif que Ion détermine à 30; pour les larves en cours de métamorphose, bien que l'effet soit moins manifeste, le dépassement du seuil de 15 révéle l'inanition. Ces résultats sont discutés en regard des travaux antérieurs, en particulier ceux fondes sur le rapport ARN/ADN. On y trouve des valeurs d'ADN/PS montrant une faible variabilité interspécifique. L'intrét de la méthode proposée est renforcé par le fait que les techniques fluorimétriques actuelles de mesure permettent de l'appliquer sans difficulté au niveau individuel.Much work has been devoted to the study of the role played by starvation in the natural field mortality of the early larval stages of marine fishes. Although different methods have been proposed, none have succeeded in including all the various advantages found. The RNA/DNA ratio suggested by many authors seems to show a variability which adversely affects its application in situ. Some conceptual considerations have led us to propose a new biochemical index, the DNA amount in the larva (expressed in μg/mg dry weight; DNA/DW). Several rearing experiments were carried out with fed and starved Dover sole (Solea solea L.) larvae under two temperature conditions. It is confirmed that the RNA/DNA ratio during ontogenetic development of fed individuals exhibits a strong variability which, moreover, is not reproducible for the same development stage between experiments carried out in strictly identical standard conditions. On the other hand, DNA/DW is proving much more stable in fed individuals and shows two main levels which are similar under the two tested temperature conditions and peculiar to symmetrical and metamorphosing larvae respectively. The effect of starvation is very sharp in the early stages, characterized by a rapid increase beyond the significant threshold of 30; for metamorphosing larvae, this effect appears to be less important and the threshold falls to 15. These results are discussed and compared with previous works, especially those based on the RNA/DNA ratio. The literature gives DNA/DW values showing a weak interspecific variability. The interest of the method is reinforced by the fact that recent fluorometric techniques allow DNA determination in ... [ABSTRACT FROM PUBLISHER]