Banca de QUALIFICAÇÃO: MARIA CLARA GONCALVES DE QUEIROZ BRITO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE: MARIA CLARA GONCALVES DE QUEIROZ BRITO
DATA : 06/10/2023
LOCAL: VIDEOCONFERÊNCIA
TÍTULO:

Mitonuclear genetics, connectivity and the stock structure of the skipjack tuna (Katsuwonus pelamis) along East and West Atlantic Ocean

PALAVRAS-CHAVES:

Skipjack tuna. Population structure. Genetic cohesiveness. West Atlantic. East Atlantic.

PÁGINAS: 20
RESUMO:

The skipjack tuna Katsuwonus pelamis is the most economically important tuna species around the world. In the Atlantic Ocean, the ICCAT management plans include the presence of two stocks: (a) eastern and (b) western Atlantic.  However, the genetic cohesiveness between them remains poorly understood. Here, we access this information using a mitonuclear approach through mitochondrial [control region d-loop (CR)] and nuclear (intron S7) data. High genetic diversity was found from both CR and S7 data, supporting the Least Concern IUCN classification, which is reinforced by the demographic data that revealed strong evidence of recent population expansions events and stability in effective population sizes of the skipjack tuna along the Atlantic. Also, these data reveal the species resilience in spite of the fisheries pressure. In general, no signal of geographic structure was recovered, which may be explained by the life history strategies of the species, such as a high population effective sizes and migratory habits, that act in reducing the isolation, endogamy and genetic drift effects. However, some weak to moderate signals of genetic differentiation were observed by pairwise FST within and between the Atlantic ICCAT stocks. Such evidence involved especially the Azores (SJ01 ICCAT area) and Saint Peter and Saint Paul Archipelago (SJ07 ICCAT area). It’s important to highlight that the major differentiation levels were found between sites from different stocks. Also, the CR data recovered a weak but significant genetic differentiation between the eastern and western stocks (FST=0.0008). These results can be used to improve and support the ICCAT management strategies of skipjack tuna stocks. However, an integrative approach using ecological and genomic data is strongly recommended in order to better understand the observed patterns, especially the genetic differentiation in Rio Grande do Norte, Azores and Saint Peter and Saint Paul Archipelago.

MEMBROS DA BANCA:
Interno - 2320121 - JOAO LUCAS LEAO FEITOSA
Externa à Instituição - MARIA RAQUEL MOURA COIMBRA
Presidente - 1330521 - RODRIGO AUGUSTO TORRES
Interna - ***.095.820-** - ROSANGELA PAULA TEIXEIRA LESSA - UFRPE