Plankton samples were collected at random sites (n = 44) and near

Plankton samples were collected at random sites (n = 44) and near whales

(n = 53) between 8 June and 9 September 2008 in Frederick Sound and Stephens Passage. The proportion of samples containing immature euphausiids, and immature euphausiid Daporinad purchase abundance within those samples, were compared between the two sample types. Similar analyses were conducted for adult euphausiids (prey) and calanoid copepods (nonprey) for comparison. I found no statistical difference between the whale and random samples with respect to the occurrence or numerical density of immature euphausiids, which is consistent with the hypothesis that whales did not target them in 2008. Smaller size, insufficient numerical densities and lower energy density of immature euphausiids are suggested as possible reasons. These findings can assist in resolving regional humpback abundance and distribution patterns, and can contribute to an understanding of the trophic interactions characterizing the local ecosystem. “
“Several different factors in the collection and preservation of whale skin and blubber samples were examined to determine their effect on MAPK Inhibitor Library clinical trial the results obtained by stable nitrogen and carbon isotope (δ15N and δ13C) analysis.

Samples of wet killer whale skin retained their original stable isotope values for up to 14 d at 4°C or lower. However, decomposition significantly changed the δ15N value within 3 d at 20°C. Storage at −20°C was as effective as −80°C for the preservation of skin and blubber samples for stable isotope analysis for at least a year. By contrast, once a skin sample had been freeze-dried and lipid extracted, the stable isotope values did not change significantly when it was stored dry at room temperature for at least 12 mo. Preservation of whale skin samples for a month in DMSO-salt solution, frozen or at room temperature, did not significantly change the δ15N and δ13C values

of lipid extracted tissues, although the slight changes seen could influence results of a study if find more only small changes are expected. “
“Capture-recapture methods relying on dorsal fin natural markings have never been applied successfully to striped dolphins, Stenella coeruleoalba, and were rarely used to assess abundance of short-beaked common dolphins, Delphinus delphis. We used digital photo-identification to obtain abundance estimates of striped and common dolphins living in mixed groups in the Gulf of Corinth, Greece. The proportion of either species was calculated based on the relative number of photographs of adult animals showing relevant portions of their body during conspicuous surfacings. Striped dolphins and common dolphins averaged 95.0% and 3.2% of all individuals, respectively. Animals showing intermediate pigmentation accounted for another 1.8%. Striped dolphin numbers were relatively high, with a point estimate of 835 animals (95% CI = 631–1,106).

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