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Anthropogenic climate change is warming global temperatures, with significant implications for salmonid fishes that depend on the availability of cold water during one or more life stages. Along the southern range extents of many species, and elsewhere that warm temperatures are increasingly problematic, identification and protection or restoration of habitats that may serve as climate refugia where local populations can persist is emerging as an important conservation tactic. In this perspective piece, we address the concept and utility of climate refugia--drawing a distinction with the more commonly considered thermal refuges--describe technological advances that enable accurate temperature mapping and species distribution modeling in lotic environments, and outline key uncertainties and opportunities to chart a constructive path forward on a topic that will continue to grow in importance. Identifying climate refugia is not a panacea for salmonid conservation, but we argue that there are tangible benefits to doing so, not the least of which are the options it affords for thinking and acting strategically within the context of a changing climate this century. Key words: stream, climate change, climate refugia, thermal refuge, salmonid, species distribution model, Introduction Salmon, trout, char, lenok, whitefish, and taimen in the family Salmonidae (hereafter, salmonids) are commonly and often interchangeably referred to as cold-water fishes due to the temperatures of their [...]

Recent and projected climate warming trends have prompted interest in impacts on coldwater fishes. We examined the role of climate (temperature and flow regime) relative to geomorphology and land use in determining the observed distributions of three trout species in the interior Columbia River Basin, USA. We considered two native species, cutthroat trout (Oncorhynchus clarkii) and bull trout (Salvelinus confluentus), as well as nonnative brook trout (Salvelinus fontinalis). We also examined the response of the native species to the presence of brook trout. Analyses were conducted using multilevel logistic regression applied to a geographically broad database of 4165 fish surveys. The results indicated that bull trout distributions were strongly related to climatic factors, and more weakly related to the presence of brook trout and geomorphic variables. Cutthroat trout distributions were weakly related to climate but strongly related to the presence of brook trout. Brook trout distributions were related to both climate and geomorphic variables, including proximity to unconfined valley bottoms. We conclude that brook trout and bull trout are likely to be adversely affected by climate warming, whereas cutthroat trout may be less sensitive. The results illustrate the importance of considering species interactions and flow regime alongside temperature in understanding climate effects on fish. Les tendances recentes et prevues de rechauffement du climat ont suscite de l'interet pour les impacts sur les poissons d'eau froide. Nous examinons le role du climat (temperature et regime hydraulique) en fonction de la geomorphologie et de l'utilisation des terres dans la determination de la repartition observee chez trois especes de <> dans le bassin versant interieur du Columbia, E.-U. Nous observons deux especes indigenes, la truite fardee (Oncorhynchus clarkii)et l'omble a tete plate (Salvelinus confluentus), ainsi que l'omble de fontaine (Salvelinus fontinalis) non indigene. Nous etudions aussi la reaction des especes indigenes a la presence de l'omble de fontaine. Les analyses consistent en des regressions logistiques a niveaux multiples sur une base de donnees de grande envergure geographique de 4165 inventaires de poissons. Les resultats indiquent que les repartitions des ombles a tete plate sont fortement reliees aux facteurs climatiques et moins fortement correlees a la presence d'ombles de fontaine et aux variables geomorphologiques. Les repartitions des truites fardees sont faiblement reliees au climat, mais fortement reliees a la presence de l'omble de fontaine. Les repartitions des ombles de fontaine sont reliees a la fois au climat et aux variables geomorphologiques, en particulier la proximite des fonds de vallees elargis. Nous concluons que l'omble de fontaine et l'omble a tete plate seront vraisemblablement affectes negativement par le rechauffement climatique, alors que la truite fardee sera peut-etre moins sensible. Nos resultats soulignent l'importance de considerer les interactions entre les especes et le regime hydraulique en plus de la temperature pour comprendre les effets du climat sur les poissons. [Traduit par la Redaction], Introduction Recent warming trends and projections of future climate change have prompted interest in the climate sensitivity of aquatic organisms (Parmesan 2006; Battin et al. 2007; McCullough et al. 2009). [...]

Movements by stream fishes have long been the subject of study and controversy. Although much discussion has focused on what proportion of fish adopt mobility within particular life stages, a larger issue involves the lifetime movements of individuals. I evaluated movements of different sizes and ages of Colorado River cutthroat trout (Oncorhynchus clarkii pleuriticus) using a variety of sampling methods from 1996 to 2001 in a 40 km network of main-stem and tributary segments of the North Fork Little Snake River, Wyoming, USA. The probability of movement was related to the period of observation, initial location, and possibly individual growth rate, whereas distance moved was related to fish size and initial location. Furthermore, it appeared that movements by juveniles were mostly downstream, whereas those of older fish were largely upstream. Movement of cutthroat trout in this basin appeared to be driven by ontogenetic changes in habitat use and variation in habitat productivity. Given that this stream network exemplifies the complexity typical of many mountain watersheds, movement as a life history tactic in fishes may be more common than is sometimes recognized. Les displacements des poissons d'eau courante ont depuis longtemps ete l'objet d'etudes et de controverses. Bien qu'une partie importante de la discussion ait porte sur la proportion de poissons qui deviennent mobiles aux differents stades de leur cycle, un probleme plus large concerne les deplacements des individus au cours de leur vie entiere. Une variete de methodes d'echantillonnage de 1996 a 2001 sur un reseau de 40 km de segments du cours principal et des tributaires de la North Fork de la riviere Little Snake, Wyoming, E.-U., a permis d'evaluer les deplacements des truites fardees du Colorado (Oncorhynchus clarkii pleuriticus) de differents ages et tailles. La probabilite de deplacement est liee a la periode d'observation, a l'emplacement initial et possiblement aussi au taux individuel de croissance, alors que la distance du deplacement est reliee a la taille du poisson et a la position initiale. De plus, il semble que les deplacements des juveniles se font surtout vers l'aval, alors que ceux des poissons plus vieux ont lieu en grande partie vers l'amont. Les deplacements de la truite fardee dans le bassin semblent s'expliquer par des changements ontogenetiques dans l'utilisation des habitats et par la variation dans la productivite de ces habitats. Comme ce reseau hydrographique est un exemple typique de la complexite de plusieurs bassins versants de montagne, le deplacement comme tactique au cours du cycle biologique des poissons pourrait etre beaucoup plus repandu qu'on le reconnait quelquefois. [Traduit par la Redaction], Introduction Movements of stream fishes have been scrutinized by biologists for decades. Early work (e.g., Shetter and Hazzard 1939) suggested that such movements might be commonplace, but many studies in [...]

Abstract: Native salmonid fishes often face simultaneous threats from habitat fragmentation and invasion by nonnative trout species. Unfortunately, management actions to address one may create or exacerbate the other. A [...]

Professor Takeyoshi Kawashima authored a famous thesis that Japanese had less of a "legal consciousness" than Americans. In part to test that thesis, a survey of Japanese attitudes toward contract law is presented. Law students' and business students' responses are gauged to determine if legal training results in a higher level of "legal consciousness."

The author discusses negotiations between the US and Japan during the early- and mid-1990s over trade matters and how those negations reflected a shift in trade ideology. Disputes between the countries over government intervention in markets and government regulation as a trade barrier are considered.