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The reorganization of patterns of species diversity driven by anthropogenic climate change, and the consequences for humans (1), are not yet fully understood or appreciated (2,3). Nevertheless, changes in climate conditions are useful for predicting shifts in species distributions at global (4) and local scales (5). Here we use the velocity of climate change (6,7) to derive spatial trajectories for climatic niches from 1960 to 2009 (ref. 7) and from 2006 to 2100, and use the properties of these trajectories to infer changes in species distributions. Coastlines act as barriers and locally cooler areas act as attractors for trajectories, creating source and sink areas for local climatic conditions. Climate source areas indicate where locally novel conditions are not connected to areas where similar climates previously occurred, and are thereby inaccessible to climate migrants tracking isotherms: 16% of global surface area for 1960 to 2009, and 34% of ocean for the 'business as usual' climate scenario (representative concentration pathway (RCP) 8.5) (8) representing continued use of fossil fuels without mitigation. Climate sink areas are where climate conditions locally disappear, potentially blocking the movement of climate migrants. Sink areas comprise 1.0% of ocean area and 3.6% of land and are prevalent on coasts and high ground. Using this approach to infer shifts in species distributions gives global and regional maps of the expected direction and rate of shifts of climate migrants, and suggests areas of potential loss of species richness., By reorganizing natural systems (2), climate change is poised to be one of the greatest threats to biodiversity of this century (3), compromising the integrity, goods and services of living [...]

Chronologies developed from annual growth-increment widths of splitnose rockfish (Sebastes pinniger) and yelloweye rockfish (Sebastes ruberrimus) otoliths were compared with time series of lay date and fledgling success for the common murre (Uria aalge) and Cassin's auklet (Ptychoramphus aleuticus) in the north-central California Current. All time series were exactly dated and spanned 1972 through 1994. In a principal components analysis, the leading principal component ([PC1.sub.bio]) accounted for 64% of the variance in the data set. By entering the upwelling index, the Northern Oscillation index, sea surface temperatures, and the multivariate ENSO (El Nino Southern Oscillation) index into principal components analysis, a time series of environmental variability [PC1.sub.env] was developed for each month of the year. Over the interval 1972 through 1994, [PC1.sub.bio] most strongly correlated with [PC1.sub.env] for February and, to a lesser extent, January and March. Moreover, when each of the six biological time series was related to the 12 [PC1.sub.env] through stepwise multiple regression, February was always the most significant (p < 0.01). The same was true if upwelling index was substituted for [PC1.sub.env]. As upper-trophic predators, rockfish and seabirds independently corroborate that wintertime ocean conditions are critical for productivity in the California Current ecosystem. Resume: Nous avons compare les chronologies obtenues a partir des largeurs des increments de croissance annuelle sur les otolithes du sebaste canari (Sebastes pinniger) et du sebaste aux yeux jaunes (Sebastes ruberrimus) et les series chronologiques des dates de ponte et du succes de l'envol chez le guillemot marmette (Uria aalge) et le starique de Cassin (Ptychoramphus aleuticus) dans le centre nord du courant de Californie. Toutes les series chronologiques portent des dates precises et couvrent la periode de 1972 a 1994. Dans une analyse des composantes principales, la premiere composante principale ([PC1.sub.bio]) explique 64 % de la variance de l'ensemble de donnees. Nous avons produit une serie chronologique de la variabilite de l'environnement [PC1.sub.env] pour chaque mois de l'annee en incluant l'indice de resurgence, l'indice d'oscillation boreale, les temperatures superficielles de la mer et l'indice multidimensionnel ENSO (oscillation australe d'El Nino) dans l'analyse des composantes principales. Dans l'intervalle de 1972 jusqu'a la fin de 1994, la [PC1.sub.bio] est le plus fortement correlee avec [PC1.sub.env] en fevrier et, a un degre moindre, en janvier et en mars. De plus, lorsque chacune des six series chronologiques biologiques est mise en relation avec les 12 [PC1.sub.env] par une regression multiple pas a pas, fevrier est toujours le mois le plus significatif (p < 0,01). Il en est de meme si on substitue l'indice de resurgence a [PC1.sub.env]. En tant que predateurs de haut niveau trophique, les sebastes et les oiseaux marins confirment de maniere independante que les conditions de l'ocean en hiver sont determinantes pour la productivite de l'ecosysteme du courant de la Californie. [Traduit par la Redaction], Introduction Climate variability is increasingly recognized as a major factor influencing structure, function, and productivity in the California Current ecosystem (CCE) of the Northeast Pacific (McGowan et al. 1998; Chavez [...]

Abstract: We tested the hypothesis of synchronous interannual changes in forage fish dynamics around the North Pacific Rim. To do this, we sampled forage fish communities using a seabird predator, [...]

Abstract: We evaluated covariation between Chinook salmon (Oncorhynchus tshawytscha) abundance and seabird breeding success in central California, USA, and compared potential forecasts to predictive models based on jack (2-year-old male) [...]

We estimated core areas and home-range sizes and evaluated sex differences in home-range size, seasonal variation in movements, and space use for breeding Common Ravens (Corvus corax) in western Marin County, California. There were no significant interannual differences in average core area or average home-range size for either sex, although there were small-scale shifts in home-range use for 67% of females and 63% of males. There was no significant difference in home-range size between the sexes. Homerange size was positively correlated with distance to food source. Ravens traveled shorter distances from the nest during the incubation + nestling stage compared to other stages of the breeding season. Core areas were centered around nest sites and food sources, with significantly aggregated locations for 83% and 100% of females in 2000 and 2001, respectively. Males were more variable in their use of space, with significantly aggregated locations for 38% and 44% of males in 2000 and 2001, respectively. Individual variation in homerange size, movements, and space use was likely due to differences in the distribution of important food sources in the area. Key words: Common Raven, core area, Corvus corax, home range, seasonal variation, sex differences, space use.

Abstract--We examined seasonal and annual variation in numbers of Steller (northern) sea lions (Eumetopias jubatus) at the South Farallon Islands from counts conducted weekly from 1974 to 1996. Numbers of [...]