A re-evaluation of the sediment distribution patterns on western Great Bahama Bank shows a facies distribution with two end-members. Coarse-grained sediments in the north, west, and south of the bank surround a mud-dominated realm located on the western leeward side of Andros Island. This facies distribution is comparable to earlier maps, but shows considerably more details and a complex distribution from grainstones to mud-rich wackestones. As in other carbonate platforms, sediment distribution appears to be influenced by (1) tidal currents, (2) prevailing wind direction, and (3) the interaction of the rate of Holocene sea-level rise with the preexisting Pleistocene topography. The grain-size distribution very precisely reflects current-influenced and protected areas on the platform. The correlation between the distribution of pellets and the 63-125µm grain-size fraction most likely reflects the predominantly biological origin of this grain size. Aragonite dominates the mineralogy on the platform, low-magnesium calcite and high-magnesium calcite occurs in higher quantities only in a few environments on the platform.

In order to investigate the spatial distribution of  13 C and  18 O of modern carbonate sediments on Great Bahama Bank, ~290 surface samples were collected from a grid of stations approximately 10 km apart between 2001 and 2004. These samples were classifi ed using a modifi ed Dunham scheme, physically separated into six size fractions and subsequently analysed for their mineralogy (aragonite, low-Mg calcite and high-Mg calcite) and  13 C and  18 O values. A striking feature of these data is the relatively positive  13 C values of all the samples. Based on measurements of  13 C and  18 O of the dissolved inorganic carbon and the water, most of the sediments can be considered to be in C and O isotopic equilibrium with the ambient waters. The high  13 C values are suggested to arise from isotopic enrichment of the dissolved inorganic carbon pool by photosynthesis of seagrasses, benthic algae and cyanobacteria on the platform and through the fractionation of HCO 3 − during the precipitation of calcium carbonate. Sediments that are not in C and O isotopic equilibrium are dominated more by skeletal material. The data showed an absence of signifi cant spatial variation in  13 C of the sediments on the Great Bahama Bank and no clear spatial patterns relative to the margin of the platform. The  18 O of the sediment showed more variation, with the interior sediments being isotopically enriched relative to the platform margin. The absence of signifi cant variations in the  13 C in the modern surface sediments of Great Bahama Bank irrespective of facies type suggests that in the case of Great Bahama Bank, downcore variations in  13 C cannot be related to changes in facies.

To understand the relative dietary value of forage fish as prey in the Bering Sea and Gulf of Alaska, whole organisms of 13 species were analysed for proximate composition (protein, oil, ash and moisture content). Eulachon (Thaleichthys pacificus) were high in oil (total lipid) (16.8% to 21.4%) and low in moisture (64.6% to 70.8%). Oil in capelin (Mallotus villosus) ranged from 2.1% to 14.0%. Juveniles of walleye pollock (Theragra chalcogramma), Atka mackerel (Pleurogrammus monopterygius), Pacific herring (Clupea pallasii), and prowfish (Zaprora silenus) had low oil contents (< 1.8%) and high moisture contents (> 80.3%). Rankings of median proximate values illustrate the similarities. Surf smelt (Hypomesus pretiosus), rainbow smelt (Osmerus mordax), pricklebacks (Lumpenus spp.), Atka mackerel, Pacific sand lance (Ammodytes hexapterus) and Pacific sandfish (Trichodon trichodon) ranked high in median protein content (> 15.4%). Median ash content for all species ranged from 0.6% to 3.3%. Total wet mass caloric content (kcal g–1) was calculated for the four main species and a linear model was developed for caloric content as a function of moisture. The linear models (caloric content = b0 + b1 × moisture) were Pacific sand lance and Pacific sandfish (b0 = 7.82, b1 = – 0.09); eulachon (b0 = 7.97, b1 = – 0.08); and capelin (b0 = 9.70, b1 = – 0.11).

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