palestras IPMA-DIVRP Tatsuya Sakamoto 19/10/2023 11:30h PT
Marta Rufino
Caros colegas,
Vimos por este meio anunciar ou relembrar, mais uma palestra no nosso ciclo de palestras do IPMA-DivRP.
Para os que planeiam assistir presencialmente, convidamos a estarem presentes na sala da presidência do IPMA (sala Luis Saldanha).
Link para o evento, titulo, resumo e biografia em baixo.
Para os participantes por zoom, é fundamental colocarem o vosso nome e instituição quando entrarem no zoom.
Até lá !
Marta e Alexandra
__________
Dear colleagues,
We hereby announce or recall, another lecture in our cycle of IPMA-DivRP lectures.
People attending in person are invited to the IPMA room.
Link to event, title, abstract and biography below.
For zoom participants, it is essential to put your name and institution when you enter the zoom.
See you then !
SAVE THE DATE
Lugar: Sala da presidência, IPMA Algés
Zoom: [LINK] Meeting ID: 914 0414 8973 / Password: 583275Nome e afiliação: Tatsuya Sakamoto (IPMA, Nova)
Titulo: Eye lens isotopes reveal population-wide mixing and migration patterns of sardine(s)
Abstract: Sardines and anchovies live in productive mid-latitude areas worldwide and provide tonnes of fisheries catches, although stock assessments and fisheries management are far from straightforward due to their mostly unknown movements in the ocean. Chemical analyses of otoliths, the calcium carbonate structures, have been an important option to study fish movements and origin. However, the skills, laboratory environment and costs required for otolith analyses are not insignificant, often limiting the feasibility or spatial and temporal scales of a study. Here, I use the example of the Japanese sardine to show that stable isotope ratios in eye lenses, which are also metabolically inert tissues but composed of protein, can be an excellent alternative for this purpose. The sardine, supporting one of the largest sardine fisheries in the world, has been believed to consist of two subpopulations, one in the western North Pacific and one in the Sea of Japan. However, our extensive analyses of the stable carbon and nitrogen isotope in the eye lenses of over 2000 individuals have revealed that the sardine population in the Sea of Japan does not form a self-sustaining subpopulation, but is largely dependent on immigrants from the western North Pacific. I will also present preliminary results for European sardine and anchovy off Portugal and discuss how the results can be used in the future.
Bio: Tatsuya Sakamoto is an isotope ecologist at the Instituto Português do Mar e da Atmosfera in Lisbon, Portugal, and works as a Japan Society for the Promotion of Science (JSPS) Overseas Research Fellow. He was a JSPS Postdoctoral Fellow at the Japan Fisheries Research and Education Agency until 2022 and received his PhD from the University of Tokyo in 2019. His wish is to explain the mechanisms driving fluctuations in marine fish populations, particularly sardines and anchovies around the world. Using stable isotope ratios in incrementally growing tissues of fish (1, 2) and cephalopods (3) (e.g. otoliths, eye lenses), he seeks to extract the history of their migration, environment and physiological state to understand how environmental fluctuations affect species' life history traits. He also develops interdisciplinary frameworks to interpret isotope chronology data, which is often noisy and influenced by variable factors, to better understand the life of marine organisms and support fisheries management.
References
1. Sakamoto, Tatsuya, et al. "Combining microvolume isotope analysis and numerical simulation to reproduce fish migration history." Methods in Ecology and Evolution 10.1 (2019): 59-69.
2. Sakamoto, Tatsuya, et al. "Contrasting life-history responses to climate variability in eastern and western North Pacific sardine populations." Nature Communications 13.1 (2022): 5298.
3. Sakamoto, Tatsuya, et al. "Stable isotopes in eye lenses reveal migration and mixing patterns of diamond squid in the western North Pacific and its marginal seas." ICES Journal of Marine Science (2023): fsad145.
_____________________________________
Portuguese Institute for the Sea and the Atmosphere (IPMA)
Centre of Statistics and its Applications (CEAUL)
Faculty of Sciences, Univ. of Lisbon, Portugal