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Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Fisheries & Aquatic Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Reviews is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Applied Physiology, Nutrition & Metabolism is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents the study which determined the effects of harvest date on switchgrass (Panicum virgatum L.) forage and silage characteristics and their relationship to specific methane yield from anaerobically digested switchgrass silage. It claims that switchgrass is native of North America. The grass has been studied as an energy crop in the U.S. and Canada.

The article presents an evaluation of the possible invasion of weed species to Canada from the U.S. It examines the potential for invasive plant species to be chosen for one or more of 10 character traits, including high growth rate, broad climatic or environmental tolerance, and short generation time. Among the plant species that were assessed are the Himalayan balsam or Impatiens glandilifera Royle and velvetleaf or Abutilon theophrasti Medic.

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Reviews is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Identification of critical habitat is a key step in conservation and recovery of endangered and threatened freshwater fish. Critical habitat under Canadian and US legislation may include habitat that is not directly used by listed fish, provided it is necessary for species conservation or recovery. Riparian habitat meets biological criteria for critical habitat because riparian zones are integral to aquatic ecosystem functions of importance to many fish species and other organisms. These functions include provision of shade for temperature-sensitive species, control of channel complexity and sediment inputs through bank stabilization, input of large wood and allochthonous energy sources, and filtering of nutrients and toxins from adjacent land. In response to decades of stream-riparian research, widespread implementation of regulations to protect riparian zones in most developed countries represent a de facto consensus that riparian buffers are essential for aquatic ecosystem health and the maintenance of populations of fish and other species. Consistent with widespread riparian regulations deemed necessary to protect not-at-risk species, riparian habitat adjacent to a body of water containing a listed freshwater species should be considered biologically critical unless the habitat requirements of individual taxa are demonstrated to be insensitive to the ecological functions associated with riparian habitat. L’identification de l’habitat critique est une étape essentielle dans la conservation et la récupération des poissons d’eau douce menacés et en voie de disparation. Dans les législations canadienne et américaine, l’habitat critique peut inclure des milieux qui ne sont pas directement utilisés par les poissons concernés, à la condition qu’ils soient nécessaires pour la conservation ou la récupération de ces espèces. Les habitats riverains possèdent les critères biologiques d’habitats critiques parce que les zones riveraines sont nécessaires pour assurer des fonctions de l’écosystème aquatique d’importance pour plusieurs espèces de poissons et pour d’autres organismes. Ces fonctions incluent la production d’ombre pour les espèces sensibles à la température, le contrôle de la complexité du chenal et des apports de sédiments par la stabilisation des rives, l’apport de sources d’énergie allochtones et de débris ligneux de grande taille et la filtration des nutriments et des toxines provenant des terres adjacentes. À la suite de décennies de recherche sur la relation entre les cours d’eau et la zone riveraine, la mise en application très commune dans la plupart des pays développés de règlements pour protéger les zones riveraines représente un consensus de facto reconnaissant que les zones tampons riveraines sont essentielles à la santé des écosystèmes aquatiques et le maintien des populations de poissons et d’autres espèces. En accord avec les règlements largement répandus sur les zones riveraines jugées nécessaires pour la protection des espèces non vulnérables, tout habitat riverain adjacent à un milieu aquatique contenant une espèce d’eau douce figurant sur la liste des espèces en péril devrait être considéré comme biologiquement critique, à moins qu’on démontre que les besoins d’habitat de ce taxon particulier sont insensibles aux fonctions écologiques associées à l’habitat riverain. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Reviews is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Genome is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

New geomorphic, paleolimnological, and radiocarbon data suggest that a terminal moraine complex in the Northern Ogilvie Mountains, Yukon Territory, Canada, may represent the McConnell Glaciation (Late Wisconsinan), rather than the Reid Glaciation (marine isotope Stage 8; Illinoian) as previously thought. Relict fluvial channels on the surface of the moraine and analysis of a suite of lake sediment cores from Chapman Lake, a closed-basin kettle on the surface of the moraine, suggest that flow from the Blackstone River passed over the moraine and through the lake until ca. 12 500 BP, at which time the Blackstone River was captured by the East Blackstone River, diverting flow from the lake. Subsequent incision by the Blackstone River has left its base level more than 10 m below the level of Chapman Lake. Perched former outlets from Chapman Lake indicate that this incision must postdate stream capture. Because the Chapman Lake moraine is a topographic barrier across the Blackstone River valley, incision must have occurred shortly after deposition of the moraine, suggesting that the landscape surrounding Chapman Lake is substantially younger than previously thought. Additional radiocarbon dates also suggest that kettle subsidence at Chapman Lake was ongoing during the early Holocene and that North Fork Pass moraine, 15 km upvalley from the Chapman Lake moraine, may have been formed during the Late Glacial rather than the McConnell Glaciation.Selon de nouvelles données géomorphologiques, paléolimnologiques et de datation au radiocarbone, un complexe de moraine terminale dans les monts Ogilvie septentrionaux, Territoire du Yukon, Canada, pourrait représenter la glaciation McConnell (Wisconsinien tardif) plutôt que la glaciation Reid (isotope marin du stade 8, Illinoien) comme on le croyait antérieurement. Selon des anciens chenaux fluviaux à la surface de la moraine et l'analyse d'un ensemble de carottes de sédiments de lac provenant du lac Chapman, un bassin de marmite à la surface de la moraine, la rivière Blackstone aurait coulé sur la moraine et à travers le lac jusqu'à environ 12 500 BP, alors qu'elle a été capturée par la rivière Blackstone Est, déviant ainsi l'écoulement loin du lac. Une incision subséquente par la rivière Blackstone a laissé son niveau de base à plus de 10 m sous le niveau du lac Chapman. D'anciens exutoires perchés du lac Chapman indiquent que cette incision doit être postérieure à la capture de la rivière. Puisque la moraine du lac Chapman constitue une barrière topographique en travers de la vallée de la rivière Blackstone, l'incision a dû se produire peu de temps après la déposition de la moraine, suggérant que le paysage autour du lac Chapman soit substantiellement plus jeune qu'on ne l'aurait crû antérieurement. D'autres dates obtenues par radiocarbone suggèrent aussi que la subsidence des marmites au lac Chapman ait eu lieu tout au cours de l'Holocène précoce et que la moraine de North Fork Pass, située à 15 km en amont de la moraine du lac Chapman, pourrait avoir été formée au cours du tardiglaciaire plutôt qu'au cours de la glaciation McConnell.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

U–Pb geochronology, palynology, and lithostratigraphy were employed on the Late Cretaceous rocks in southern Alberta and Montana to solve litho- and chronostratigraphic correlation problems. In the outcrop area around Writing-On-Stone Provincial Park, southern Alberta, the Milk River Formation has a Santonian to possibly very earliest Campanian age and was deposited between ~84.5 Ma and 83.5 Ma. In southern Montana, the Eagle Formation was deposited from ~83.5 Ma to 81.2 Ma, and contains different lithologies and depositional environments as opposed to southern Alberta. In north-central Montana, the Telegraph Creek Formation and Virgelle and Deadhorse Coulee members are equivalent in depositional environments and time to those of the Milk River Formation in southern Alberta. The upper Eagle member, however, has no time- or facies-equivalent rocks around Writing-On-Stone Provincial Park, but is time equivalent to the Alderson Member of the Lea Park Formation in southeastern Alberta. A hiatus of ~2.5 Ma is present between the top of the Milk River Formation in the outcrop area and the basal beds of the Pakowki Formation. The Pakowki transgression occurred at around 81.0 Ma based on a U–Pb zircon age of 80.7 ± 0.2 Ma from bentonite beds just above the bottom of the Pakowki Formation in southern Alberta. This age agrees with previous ages of 80.7 ± 0.6 Ma for the Ardmore Bentonite Beds and ~81.0 Ma for the Claggett transgression in southern Montana.Afin de résoudre des problèmes de corrélations lithostratigraphiques et chronostratigraphiques, on s'est servi de géochronologie U–Pb, de palynologie et de lithostratigraphie sur des roches du Crétacé tardif du sud de l'Alberta et du Montana. Dans la région des affleurements autour du parc provincial de Writing-On-Stone, au sud de l'Alberta, la Formation de Milk River date possiblement du Santonien au Campanien très précoce et aurait été déposée il y a environ 84,5 à 83,5 Ma. Dans le sud du Montana, la Formation Eagle a été déposée il y a environ 83,5 à 81,2 Ma; elle présente des lithologies et des milieux de déposition différents de ceux du sud de l'Alberta. Dans le centre-nord du Montana, la Formation de Telegraph Creek et les membres Virgelle et Deadhorse Coulee ont des milieux et des temps de déposition équivalents à ceux de la Formation de Milk River du sud de l'Alberta. Toutefois, le membre supérieur de Eagle n'a d'équivalent ni dans le temps ni dans les faciès dans les roches autour du parc provincial de Writing-On-Stone, mais il est équivalent dans le temps au membre Alderson de la Formation de Lea Park dans le sud-est de l'Alberta. Il existe un hiatus d'environ 2,5 Ma entre le sommet de la Formation de Milk River dans la région des affleurements et les lits à la base de la Formation de Pakowki. La transgression de Pakowki a eu lieu vers 81,0 Ma selon une détermination d'âge U–Pb de 80,7 ± 0,2 Ma sur un échantillon de zircon provenant de lits de bentonite juste au-dessus de la base de la Formation de Pakowki dans le sud de l'Alberta. Cet âge concorde avec des âges obtenus antérieurement de 80,7 ± 0,6 Ma pour les lits de bentonite Ardmore et d'environ 81,0 Ma pour la transgression de Claggett dans le sud du Montana.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Chasmosaurus irvinensis (sp. nov.) is distinguished from other species of this genus by the possession of a broad snout, absence of a brow horn (the position of which is occupied by a pit or rugosities suggestive of bone resorption), broadly rounded and open jugal notch, subrectangular squamosal, straight posterior parietal bar bearing 10 epoccipitals, eight of which are flattened, strongly curved anterodorsally, and nearly indistinguishably coossified to their neighbours, and small, transversely oriented parietal fenestrae restricted to the posterior portion of the frill. This species, restricted to the upper part of the Dinosaur Park Formation, is significantly younger than the other recognized Canadian Chasmosaurus species, C. belli and C. russelli. Phylogenetic analysis shows that C. irvinensis is most closely related to the other Canadian Chasmosaurus species and more distantly related to Chasmosaurus mariscalensis from Texas.Chasmosaurus irvinensis (sp. nov.) se distingue des autres espèces de ce genre par son large boutoir, l'absence d'une corne sur le front (cette position est occupée par une fossette ou des rugosités qui suggèrent une résorption osseuse), une encoche jugale généralement arrondie et ouverte, un temporal presque rectangulaire, une barre pariétale postérieure droite comportant 10 époccipitaux, dont huit sont aplatis et fortement recourbés, dirigées en position antéro-dorsale et co-ossifiés à leurs voisins de façon presque indistincte, ainsi que de petites fenêtres pariétales à orientation transversale restreintes à la partie arrière de la collerette. Cette espèce, limitée à la portion supérieure de la Formation de Dinosaur Park, est beaucoup plus jeune que les autres espèces canadiennes de Chasmosaurus, C. belli et C. russelli. Une analyse phylogénique montre que C. irvinensis est plus étroitement lié aux autres espèces canadiennes de Chasmosaurus et moins étroitement lié au Chasmosaurus mariscalensis du Texas.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

The Quottoon plutonic complex (part of the great tonalite sill) was emplaced into eastern parts of the Coast shear zone along the west flank of the Coast Mountains. U–Pb crystallization ages range from 72.3 to 55.5 Ma. A regional compilation of K–Ar hornblende dates from the tonalite sill indicates a west to east decrease from ~60 Ma to ~54 Ma across the intrusive suite. Paleomagnetic samples were collected at 160 sites ( 8 samples per site) along six transects across the Quottoon complex between the Skeena River and Willard Inlet. Directions of characteristic remanent magnetization (ChRM) were successfully determined by principal component analysis of thermal demagnetization data for about half of the samples collected. Site-mean ChRM directions were determined for 56 sites from the Skeena River, Quottoon Inlet, Steamer Passage, and Wales Island transects, using criteria of 4 sample ChRM directions per site and 95% confidence limit (α[sub 95] ) 25°. For Filmore Island and Willard Inlet, few sites provided adequate determinations of site-mean ChRM directions, but many sample ChRM directions were well determined and consistent. The mean direction from the Skeena River – Quottoon Inlet collection is nearly concordant with the expected Eocene direction. Mean directions from other transects have clockwise-rotated declinations and inclinations that are shallower than the expected direction by up to 23°. Consistent with expectations for east-side-up tilting of crustal panels, sites from the western part of each transect have mean directions farther from the Eocene expected direction than do sites from the eastern part of the transect. The magnitude of east-side-up tilt varies along strike: the Skeena River to Quottoon Inlet segment experienced little or no tilt; Steamer Passage south of Portland Inlet records 15° tilt; north of Portland Inlet, tilts are 40° for Wales Island and 35° for Filmore Island; farther north, tilt decreases to 12° for Willard Inlet. Tilting was driven by Eocene extension of the Coast Mountains, with tilted crustal panels bounded by northwest-striking, east-side-down normal faults and northeast-striking transfer faults or shear zones. The ACCRETE seismic transect imaged east-dipping reflectors down to ~15 km depth, which likely correspond to the east-side-down normal faults. The most significant of the northeast-striking transfer structures must underlie Portland Inlet. Based on a tilting domino model, about 30% extension is required to produce the 40° tilt of crustal blocks at Wales and Filmore islands.Le complexe plutonique Quottoon (une partie du grand filon-couche de tonalite) a été mis en place dans des parties orientales de la zone de cisaillement côtière le long du flanc ouest de la chaîne Côtière. Des âges de cristallisation U–Pb vont de 72,3 à 55,5 Ma. Une compilation régionale de datations K–Ar sur des hornblendes provenant du filon-couche de tonalite indique une décroissance d'ouest en est à travers la suite intrusive de ~60 Ma à ~54 Ma. Des échantillons paléomagnétiques ont été recueillis sur 160 sites ( 8 échantillons par site) le long de six transects à travers le complexe de Quottoon, entre la rivière Skeena et l'inlet Willard. Pour environ la moitié des échantillons recueillis, les directions du magnétisme rémanent caractéristique (ChRM) ont été déterminées avec succès par une analyse des composantes principales de la démagnétisation thermique. Les moyennes des directions ChRM ont été déterminées par site pour 56 sites situés sur les transects de la rivière Skeena, de l'inlet Quottoon, du passage Steamer et de l'île de Wales, utilisant des critères de 4 directions ChRM sur des échantillons par site et une limite de confiance de 95 % (α[sub 95] ) 25º. En ce qui concerne l'île Filmore et l'inlet Willard, peu de déterminations adéquates de directions moyennes ChRM spécifiques au site ont été obtenues; cependant, plusieurs directions ChRM sur les échantillons étaient bien déterminées et cohérentes. La direction moyenne de la collecte provenant de la rivière Skeena – inlet Quottoon concorde presque avec la direction escomptée de l'Éocène. Les directions moyennes d'autres transects ont des déclinaisons et des inclinaisons à rotation de sens horaire qui sont jusqu'à 23º moins profondes que les directions escomptées. Les sites de la portion ouest de chaque transect ont des directions moyennes divergeant plus de la direction escomptée à l'Éocène que les sites de la partie est du transect, ce qui concorde avec les attentes d'un basculement du côté est vers le haut de grands blocs de la croûte. L'amplitude du basculement du côté est vers le haut varie selon la direction : le segment entre la rivière Skeena et l'inlet Quottoon n'a pas ou a peu basculé; le passage Steamer, au sud de Portland Inlet, enregistre 15º de basculement; au nord de l'inlet Portland, le basculement est de 40º pour l'île de Wales, 35º pour l'île Filmore et, plus au nord, l'inclinaison diminue à 12º pour l'inlet Willard. Le basculement provient de l'extension, à l'Éocène, de la chaîne Côtière au moyen de grands blocs inclinés de la croûte limités par des failles normales à direction nord-ouest et le côté est vers le bas et par des failles de transfert ou des zones de cisaillement à direction nord-est. Le transect sismique « ACCRETE » a interprété des réflecteurs à pendage est jusqu'à ~15 km de profond qui correspondent probablement au failles normales à côté est vers le bas. La plus importante des structures de transfert à direction nord-est doit se trouver sous l'inlet Portland. Selon une théorie de basculement de dominos, il faut une extension de 30 % pour basculer de 40º les blocs de la croûte aux îles de Wales et de Filmore.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We examined spatial patterns of covariation in indices of survival rate (residuals from the best-fit stock- recruitment curve) across four decades among 43 wild pink salmon (Oncorhynchus gorbuscha) stocks from 14 geographical regions in Washington, British Columbia, and Alaska. We found strong evidence of positive covariation among stocks within each region and between certain adjacent regions (e.g., correlations from 0.3 to 0.7) but no evidence of covariation between stocks ofdistant regions (e.g., separated by 1000 km or more). This suggests that important environmental processes affecting temporal variation in survival rates of pink salmon from spawners to recruits operate at regional spatial scales rather than at the larger ocean basin scale. Based on limited fry abundance data, we found that this covariation in spawner-to-recruit survival rates may be strongly influenced by marine processes. [ABSTRACT FROM AUTHOR]

This paper summarizes available information on patterns of physical activity, their determinants and consequences, and the results of various interventions designed to increase the physical activity of Aboriginal peoples in Canada and the United States. There is a paucity of national data on this issue for Aboriginal peoples. The most recent data, from the First Nations Regional Longitudinal Health Survey of 2002-2003, indicate that 21% of adults (27% of men, 15% of women) were engaging in at least 30 min of moderate to vigorous physical activity on 4 d/week or more. The present paper highlights the unique challenges this group faces, underlining the need to integrate collective knowledge regarding how much physical activity is required for Aboriginal Canadians, and how this activity should be accomplished, to promote and maintain health. Efforts are currently underway to tailor Canada's physical activity guide for First Nations, Inuit, and Métis. Future research among Aboriginal groups should examine the minimal and optimal levels of physical activity required to achieve health benefits.