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Kim Vane

Institution: Leibniz Center for Tropical Marine Ecology (ZMT), Bremen
Room: ZMT, room 1108
Phone: +49 421 23800 - 30
E-mail: [Bitte aktivieren Sie Javascript]
Other webpage(s): Kim's ZMT web page
Kim Vane

PhD project:

Element and stable isotope analysis as means for comparative investigations on life performance at different time scales

Migration and habitat use of fish are important parameters in the conservation of fish populations. However, they are very difficult to investigate, mainly due to the large aquatic areas fish often move in and labour intensive tracking methods. Fish otoliths, on the contrary, are relatively easy to collect and its chemistry can provide information on movement patterns.

Otoliths are calcium carbonate structures that are located in the inner head of the fish and which are used for balance and hearing. The accretion of calcium carbonate occurs from the early embryonic stage and throughout the fish life on a daily basis. At the same time, elements, their isotopes and organic matter are incorporated in the otolith matrix. These compounds can to a certain level be linked to the chemistry of the aquatic environment the fish moves in. As such the otolith chemistry provides us with an ‘easy’ indicator for movement patterns of fish over chemically different aquatic areas.

Compound specific isotope analysis (CSIA) measures the δ13C of essential amino acids (EAAs) in the organic part of the otolith and allows us to uncover a direct link from the fish to the primary producers at the base of the foodweb. This is due to the fact that animals, such as fish, are not able to produce EAAs and have to directly assimilate these molecules from the primary producers. Therefore, trophic fractionation as with bulk isotope analysis does not occur. EAAs can thus serve as a valuable tool to obtain detailed information on habitat use and connectivity of fish.

My research focuses on using otolith chemistry to understand the movement and habitat use patterns of the Brazilian weakfish, Cynoscion acoupa, in north- eastern Brazil. This highly valued commercial species uses the coastal mangrove areas as nursery areas for its juvenile life stage, while the adults are found in the open ocean. Nonetheless, little is known about which habitats are important for different life stages and how these large adults move along the coast of Brazil. Otolith element and isotopes, genetics and δ13C of EAAs will be used to gain a better insight in the life history and ecology of this Brazilian fish species.

Thesis committee:

Dr. Werner EkauLeibniz Center for Tropical Marine Ecology (ZMT), Bremen
Prof. Dr. Hildegard WestphalLeibniz Center for Tropical Marine Ecology (ZMT), Bremen
Dr. Hauke ReuterLeibniz Center for Tropical Marine Ecology (ZMT), Bremen
Dr. Barbara Schulz-BöttcherInstitute for Chemistry and Biology of the Marine Environment (ICBM), Oldenburg