Impacts of Southern Ocean warming on marine connectivity: Integrating oceanographic modelling with molecular ecology and developmental biology

Lead Research Organisation: British Antarctic Survey
Department Name: Science Programmes

Abstract

See lead proposal (Bangor) for details.
 
Description Understanding the key drivers of population connectivity in the marine environment is essential for the effective management of natural resources. Although several different approaches to evaluating connectivity have been used, they are rarely integrated quantitatively to elucidate the drivers of population genetic structuring. Here, we used a 'seascape genetics' approach, combining complementary approaches of numerical modelling and microsatellite analyses, to understand the dominant influences on the population genetic structure of Champsocephalus gunnari and Notothenia rossii. The close accord between the model projections and empirical genetic structure demonstrates that connectivity during the planktonic early life stages is the dominant influence on patterns and extent of genetic structuring in both species. The shorter planktonic phase of C. gunnari restricts direct transport of larvae between distant populations, leading to stronger regional differentiation; genetic structuring is dictated by the underlying oceanographic flows, which influence the direction and magnitude of stepping-stone transport routes. Inter-annual variability in oceanographic flows strongly impacted the projected genetic structure, suggesting that shifts in circulation patterns due to climate change are likely to impact future genetic connectivity and opportunities for local adaptation, resilience and recovery from perturbations. Further development of realistic climate models is required to fully assess such potential impacts.
Exploitation Route Management of the fishery as well as impacts of climate change on population structure and exploitation.
Sectors Agriculture, Food and Drink,Environment
 
Title Species-specific Individual Based Models for 4 species of Antarctic fish 
Description Individual Based Models have been developed specific to the early life stages (eggs and planktonic larvae) of 4 species of Antarctic fish: Champsocephalus gunnari, Notothenia rossii, Gobionotothen gibberifrons and Chaenocephalus aceratus. The parameterisation of these models is specific to populations within the Scotia Sea, but could easily be adapted to populations in other Antarctic and sub-Antarctic regions. These models have been used to simulate connectivity between isolated populations of the 4 fish species, and subsequently to project, and understand the dominant influences on, the genetic structure of Scotia Sea fish populations. 
Type Of Material Computer model/algorithm 
Provided To Others? No  
Impact The models, in conjunction with published theory on the impact of rising temperatures on egg and larval durations and mortality rates, have been used to project the impact of rising sea temperatures on gene flow in the Scotia Sea, and the potential for increasing genetic isolation of sub-Antarctic island fish populations. The research is therefore of great interest to fisheries scientists, climate change researchers and international bodies involved in the management of Southern Ocean ecosystems, such as CCAMLR. 
 
Description Presentation at 39th Annual Larval Fish Conference 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact Presentation to conference delegates comprising research scientists and postgraduate students, entitled 'Oceanography and life history predict contrasting larval dispersal and genetic population structure in two Antarctic fish species'. The presentation generated much interest and discussion, and furthered collaborations with international scientists.
Year(s) Of Engagement Activity 2015
 
Description Presentation at Ocean Sciences 2014 conference 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Much interest in the project was generated by my presentation, including questions immediately following the talk, and discussions during conference breaks over the following few days.

Following my presentation at the Ocean Sciences meeting, I have been invited to present further aspects of the work undertaken as part of the project at the 39th larval fish conference in Vienna, 2015.
Year(s) Of Engagement Activity 2014
URL http://www.sgmeet.com/osm2014/viewabstract.asp?AbstractID=13538
 
Description Presentation at Ocean Sciences 2016 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact Presentation to predominantly research scientists and postgraduate students, entitled 'Degrees of Isolation: The Impact of Climate Change on the Dispersal and Population Genetic Structure of Two Antarctic Fish Species'. The presentation generated much interest and furthered collaborations with both national and international scientific colleagues.
Year(s) Of Engagement Activity 2016
 
Description Presentation at XIIth SCAR Biology Symposium 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact Oral presentation to international scientists entitled 'Degrees of Isolation: The Impact of Climate Change on the Dispersal and Population Genetic Structure of Two Antarctic Fish Species'. Discussions arising from the talk have led to opportunities for future collaboration with international scientists.
Year(s) Of Engagement Activity 2017