演題及び演者：
南大洋のイカと脂肪酸による摂餌分析
Katrina Phillips 氏 （外洋いか研究室、外国人特別研究員）
時間：10月7日（木） 午後4：00より＠大会議室
講演内容：
The squid fauna are a key component of the Southern Ocean, although as yet we know little of their distribution, biology and ecology. While the biomass of squid in the Southern Ocean must impose a large amount of predatory pressure on lower trophic levels, few dietary data exist for any of the Southern Ocean species. Conventional dietary analyses of squid are fraught with many sources of bias, and I have used conventional stomach contents analyses in addition to fatty acid analyses to investigate several aspects of the diet of the Southern Ocean species Moroteuthis ingens. The digestive gland (or liver) of Moroteuthis ingens was found to be an ideal source of fatty acid dietary tracers that were unmodified from the diet and as such provided important information on the dietary habits of this squid. On of the most important features fatty acid analysis is that it utilises an actual tissue of the squid; it is not reliant on stomach contents and can therefore provide truly complementary information on diet. This provides a significant advantage over other techniques, such as DNA analysis of stomach contents, which although have the potential to provide specific prey species information are nevertheless vulnerable to the same biases that constrain conventional stomach content analyses in the first instance. The application of fatty acid analysis to dietary research of squid is illustrated with examples from my Ph. D., including the determination of temporal, spatial and size-related shifts in the diet of Moroteuthis ingens collected from various regions of the Southern Ocean.
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