Growth and survival of the red sea urchin Strongylocentrotus franciscanus were studied at 18 sites from southern California to Alaska. USA. Growth was determined using tetracycline tagging and was modeled using the Tanaka growth equation. Survival rates were estirnated using size-frequency distributions and growth parameters. Using log-linear analysis, it was determined that growth transitions differed among sites (p G 0.001) but there was no north-south difference (p > 0.80). Parameters for the Tanaka growth function were estimated for all data combined (N = 2714). Residuals for sites showed no latitudinal trend and so results were consistent with the log-linear analysis. Relative jaw (demi-pyramid) size, measured as the allometnc exponent ß in jaw length as a function of test diameter, has been shown to b e responsive to available food. For red sea urchins, ß was negatively correlated with growth but there was no correlation of relative jaw size with latitude, which suggests that latitudinal differences in food availability do not exist. In contrast with annual growth rates, annual survival rates were correlated with latitude and were higher in the north. Mean annual survival probability was 0.93 yr-' from northern California to Alaska and 0.77 yr-' in southern California. Likely causes for changes in survival rate with latitude are disease and temperature-related Stress. This paper provides the basis for development of hypotheses for size and survival differences between northern and southern populations of red sea urchins and. potentially, for other marine species with planktonic larvae.

Murres were abundant over the continental shelf and scarce over deep oceanic water in the southeastern Bering Sea during April 1978 and 1979. They occurred in scattered flocks and in patches averaging 26 birds.km-' within a 300-x 450-km area. Thick-billed murres (Uris lomvia), the most common species, concentrated between shelfbreak and a middle front at the 100-m isobath, where a trophically rich pelagic system supports shallow patches of fish and zooplankton.There were fewer murres inshore of the middle front, and these were mostly common murres (Uris aalge). The densest patches of fish and zooplankton in the study area were as long as 50 and 35 km. The distribution of murres was not closely tied to that of fish in either year and corresponded to zooplankton distribution in the second year only. Murres may be feeding where prey concentrations are low or minimal, and frequent storms interfere with feeding.

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The goals of this study were to characterize growth of the commercially harvested red sea urchin Strongylocentrotus franciscanus in southeastern Alaska and test the validity of an aging technique. We aged urchins by counting growth rings on a part (rotula) of the Aristotle's lantern complex from urchins collected at three sites. A subset of collected urchins had three or more years of size measurements from passive integrated transponder (PIT) tag data, allowing us to fit and compare PIT tag and ring-derived growth curves and test the assumption that rings were formed annually. Growth from PIT-tagged individuals approximated the growth derived from ring counts for two of three sites. The third site deviated slightly from predicted growth, providing support for our aging technique. However, we failed to detect any extremely old urchins, suggesting that this technique is not appropriate for assessing the longevity or growth trajectory of very large urchins. An additional five sites without PIT-tagged urchins were sampled to examine spatial variation in growth. Estimates of time to fishery entry varied substantially among sites, but four nonlinear growth functions produced similar estimates at individual sites. Time to fishery entry was positively correlated with an index of food availability, which suggests that the technique revealed true variation in growth rates.