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a current synthesis b y g E o r g E w. b o E h l E r t a N d a N d r E w b . g i l l m a r i N E r E N E wa b l E E N E r g y | i N a r E g u l ato ry E N V i r o N m E N t iNtroductioN Renewable energy resources may represent one of humankind's best hopes for reducing our substantial contribution to global warming (Krupp and Horn, 2008). Technology to capture the energy from wind, the sun, and biomass are all in various stages of development. In many areas of the world, marine renewable energy has great promise but many of the approaches remain to be developed to commercial standards. Energy from marine wind, tides, currents, waves, and thermal gradients may all hold immense potential for electrical energy generation. The development of the technology, however, is not without environmental and social concerns (Pelc and Fujita, 2002;Gill, 2005;Cada et al., 2007;Boehlert et al., 2008;Inger abstract. Marine renewable energy promises to assist in the effort to reduce carbon emissions worldwide. As with any large-scale development in the marine environment, however, it comes with uncertainty about potential environmental impacts, most of which have not been adequately evaluated-in part because many of the devices have yet to be deployed and tested. We review the nature of environmental and, more specifically, ecological effects of the development of diverse types of marine renewable energy-covering marine wind, wave, tidal, ocean current, and thermal gradient-and discuss the current state of knowledge or uncertainty on how these effects may be manifested. Many of the projected effects are common with other types of development in the marine environment; for example, additional structures lead to concerns for entanglement, habitat change, and community change. Other effects are relatively unique to marine energy conversion, and specific to the type of energy being harnessed, the individual device type, or the reduction in energy in marine systems.While many potential impacts are unavoidable but measurable, we would argue it is possible (and necessary) to minimize others through careful device development and site selection; the scale of development, however, will lead to cumulative effects that we must understand to avoid environmental impacts. Renewable energy developers, regulators, scientists, engineers, and ocean stakeholders must work together to achieve the common dual objectives of clean renewable energy and a healthy marine environment.This article has been published in Oceanography, Volume 23, Number 2, a quarterly journal of The oceanography society.

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We applied crossdating, a dendrochronology (tree-ring analysis) age validation technique, to growth increment widths of 50 Sebastes diploproa otoliths ranging from 30 to 84 years in age. Synchronous growth patterns were matched by the following: (i) checking the dates of conspicuously narrow growth increments for agreement among samples and (ii) statistically verifying that growth patterns correlated among samples. To statistically verify pattern matching, we fit each time series of otolith measurements with a spline, and all measurements were divided by the values predicted by the curve. This standardized each time series to a mean of 1, removing the effects of age on growth and homogenizing variance. Each time series was then correlated with the average growth patterns of all other series, yielding an average correlation coefficient (r) of 0.53. Average growth of all 50 samples was significantly correlated with an upwelling index (r = 0.40, p = 0.002), the Pacific Decadal Oscillation (r = -0.29, p = 0.007), and the Northern Oscillation Index (r = 0.51, p = 0.0001), corroborating accuracy. We believe this approach to age validation will be applicable to a wide range of long-lived marine and freshwater species.Résumé : Nous avons utilisé la datation croisée, une technique de validation de l'âge en dendrochronologie (analyse des anneaux des arbres), pour étudier les largeurs des incréments de croissance des otolithes de 50 Sebastes diploproa, âgés de 30 à 84 ans. Les patrons de croissance synchronisée ont été corroborés (i) en nous assurant que les dates d'incréments particulièrement étroits correspondent dans les échantillons et (ii) en vérifiant statistiquement que les patrons de croissance sont en corrélation dans les différents échantillons. Pour vérifier statistiquement la correspondance des patrons, chaque série chronologique de mesures d'otolithes est ajustée à une spline et toutes les mesures sont divisées par les valeurs prédites par la courbe. Cette opération standardise chaque série chronologique autour d'une moyenne de 1, éliminant les effets de l'âge sur la croissance et rendant la variance homogène. Chaque série chronologique est alors mise en corrélation avec le patron de croissance moyen des autres séries, ce qui génère un coefficient de corrélation (r) moyen de 0,53. La croissance moyenne de l'ensemble des 50 échantillons est en corrélation significative avec l'indice d'affleurement (upwelling) (r = 0,40, p = 0,002), l'oscillation décennale du Pacifique (r = -0,29, p = 0,007) et l'indice d'oscillation boréale (r = 0,51, p = 0,0001), ce qui confirme sa précision. Nous croyons que cette méthode de validation de l'âge pourra s'appliquer à une variété d'espèces de mer et d'eau douce à grande longévité.[Traduit par la Rédaction] Black et al. 2284

Fishes inhabiting estuaries, rivers, and embayments are subject to turbid conditions. Larvae of many fishes utilize estuaries as nursery areas. For visual plankton feeders such as larval fishes, turbidity may reduce search and reaction distances, resulting in lowered feeding abilities. In this study feeding Pacific herring larvae, Clupea harenguspallasi, were exposed to suspensions of estuarine sediment and Mount Saint Helens volcanic ash at concentrations ranging from0 mg .

Eight temperature‐recording data storage tags were recovered from three salmonids in Alaska (pink and coho salmon and steelhead trout) and five chum salmon in Japan after 21–117 days, containing the first long‐term records of ambient temperature from Pacific salmonids migrating at sea. Temperature data imply diel patterns of descents to deeper, cooler water and ascents to the surface. Fish were found at higher average temperatures at night, with narrower temperature ranges and fewer descents than during the day. Fish tagged in the Gulf of Alaska were at higher temperatures on average (10–12°C) than chum salmon tagged in the Bering Sea (8–10°C). Chum salmon were also found at a wider range of temperatures (−1–22°C vs 5–15°C). This is probably related both to the different oceanographic regions through which the fish migrated, as well as species differences in thermal range and vertical movements. Proportions of time that individual fish spent at different temperatures seemed to vary among oceanographic regions. Steelhead trout may descend to moderate depths (50 m) and not be limited to the top few metres, as had been believed. Japanese chum salmon may seek deep, cold waters as they encounter warm surface temperatures on their homeward migrations. Temperature data from all fish showed an initial period (4–21 days) of day and night temperatures near those of sea surface temperatures, suggesting a period of recuperation from tagging trauma. A period of tagging recuperation suggests that vertical movement data from short‐term ultrasonic telemetry studies may not represent normal behaviour of fish. The considerable diurnal and shorter‐term variation in ambient temperatures suggests that offshore ocean distribution may be linked more to prey distribution and foraging than to sea surface temperatures.

For most of history, the ocean has remained nearly opaque to study, and it has been difficult to understand where salmon or other marine animals go or how they use the ocean. This greatly limits the ability of oceanographers and fisheries biologists to improve the management of many marine resources. The technical and scientific basis now exists to track the ocean movements of individual marine fish for months or years at a time. In this article, we review how new technologies might be applied to salmon in particular. Our conclusion is that animals as small as juvenile Pacific salmon can be followed for months to years at sea, and thus over great distances. By identifying the migration pathways for individual salmon and specific populations of Pacific salmon, we can establish their ocean foraging grounds. We outline the approaches and initial results from the Census of Marine Life program pacific ocean salmon tracking (POST). The research program involves two distinct aspects: (1) the development of an acoustic array for tracking the movements of Pacific salmon during their shelf-resident phase of the life history and (2) the use of archival (data storage) tags to measure aspects of their local environment and to delineate their open ocean migration pathways off the shelf. We report on some of the preliminary findings from the first year of the field project using acoustic tags.