Project overview

The Patagonian long-finned squid Doryteuthis gahi inhabits coastal waters around the Southern tip of South America and supports a commercially important and economically valuable fishery within Falkland Islands Waters.

The fishery operates within two seasons corresponding to two seasonally distinct cohorts, the autumn spawning cohort (ASC) and spring spawning cohort (SSC).

Though the population of D.gahi has been found to be genetically homogenous within Falkland Island Waters, the mechanisms connecting different geographically and temporally separate regions are unknown. Cephalopods are characterised by short annual lifecycles. With no reservoir of older individuals to buffer against poor recruitment periods, they have developed complicated reproductive strategies to ensure survival. It is still unknown how these strategies are applied to maintain the connectivity within this population.

This PhD aims to better understand the reproductive dynamics and level of population connectivity within the Falkland Island D.gahi population, to inform sustainable fisheries management.

Several potential mechanisms for genetic exchange have been generated and will be assessed using a combination of; historic data analysis, statolith ageing, laser ablation ICP-MS, gladii increment analysis and collection of morphometric parameters.

Project Highlights

Generating multi-elemental profiles of squid statoliths using laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) with the British Geological Survey, Nottingham. In addition, I participated in two pre-recruitment research surveys (FV Castelo in the second season and FV Argos Vigo in the first season) as lead scientist for the D.gahi fishery.

Highlights of July 18 – June 19
On the 17th December Jess's thesis was submitted for consideration. In February her second manuscript was accepted for publication in Marine and Freshwater Research and in March her third manuscript was accepted to Marine Biology. Jess's Viva was conducted in Aberdeen on 10th April and she passed with no corrections. Jess has since started a position as Post-Doctoral researcher with the Falkland Islands Fisheries Department on the same species.