The 2011 East Japan earthquake generated a massive tsunami that launched an extraordinary transoceanic biological rafting event with no known historical precedent. We document 289 living Japanese coastal marine species from 16 phyla transported over 6 years on objects that traveled thousands of kilometers across the Pacific Ocean to the shores of North America and Hawai'i. Most of this dispersal occurred on nonbiodegradable objects, resulting in the longest documented transoceanic survival and dispersal of coastal species by rafting. Expanding shoreline infrastructure has increased global sources of plastic materials available for biotic colonization and also interacts with climate change-induced storms of increasing severity to eject debris into the oceans. In turn, increased ocean rafting may intensify species invasions.

Aim  We examine the regional dominance of California as a beachhead for marine biological invasions in western North America and assess the relative contribution of different transfer mechanisms to invasions over time. Location  Western North America (California to Alaska, excluding Mexico). Methods  We undertook extensive analysis of literature and collections records to characterize the invasion history of non‐native species (invertebrates, microalgae and microorganisms) with established populations in coastal marine (tidal) waters of western North America through 2006. Using these data, we estimated (1) the proportion of first regional records of non‐native species that occurred in California and (2) the relative contribution of transfer mechanisms to California invasions (or vector strength) over time. Results  Excluding vascular plants and vertebrates, we identified 290 non‐native marine species with established populations in western North America, and 79% had first regional records from California. Many (40–64%) of the non‐native species in adjacent states and provinces were first reported in California, suggesting northward spread. California also drives the increasing regional rate of detected invasions. Of 257 non‐native species established in California, 59% had first regional records in San Francisco Bay; 57% are known from multiple estuaries, suggesting secondary spread; and a majority were attributed to vessels (ballast water or hull fouling) or oysters, in some combination, but their relative contributions are not clear. For California, more than one vector was possible for 56% of species, and the potential contribution of ballast water, hull fouling and live trade increased over time, unlike other vectors. Main conclusions  California, especially San Francisco Bay, plays a pivotal role for marine invasion dynamics for western North America, providing an entry point from which many species spread. This pattern is associated historically with high propagule supply and salinity. Any effective strategies to minimize new invasions throughout this region must (1) focus attention on California and (2) address current uncertainty and future shifts in vector strength.

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We investigated the relationship between large-scale climate variability (the North Atlantic Oscillation, NAO), continental shelf hydrography, and year-class strength of yellowtail flounder (Limanda ferruginea) in the Middle Atlantic Bight. Using long-term environmental time series , dominant winter NAO phase in the northeast region of the United States was correlated with local air temperature records from Block Island, Rhode Island (December-March). Air temperature also influenced the characteristics of a pool of remnant winter cold water on the continental shelf, such that negative NAO winters produced a colder-than-average summer cold pool, and vice versa.Smoothed data sets of L. ferruginea recruitment over the 36-yr period (using Southern New England VPA and hindcast data) were highly correlated with the NAO and air temperature, highlighting the influence of multi-year variability. Although less robust, the relationship with the NAO remained significant after removing equal-but-opposite long-term linear trends from the series. Surprisingly, recruitment and cold pool bottom temperature were only marginally correlated. Data from independent 2-m beam trawl and submersible sampling in the region (1994,(1996)(1997)(1998)(1999)(2000) indicated a strong relationship between the abundance of recent settlers and cold pool temperature; however, this pattern was often modified by subsequent changes in cold pool stratification (fall overturn). These results underscore the dynamic role thermal habitats play in the lives of early stage benthic fishes. For yellowtail flounder, the generation of recruitment variability represents one endpoint of a complex interaction between large-scale phenomena (climate) and more localized, event-scale features (cold pool).