Introduction

This Work Package will evaluate changes in marine biodiversity and ecosystem functioning in the coastal seas of the west Antarctic Peninsula as a result of the onset of extensive whaling in the early twentieth century. The Antarctic coastal seas were effectively pristine prior to discovery of the continent in the eighteenth century which was followed by small-scale sealing penetrating south of the Antarctic Circle. However, intensive whaling did not commence until the twentieth century by British and Norwegian whaling fleets operating out of South Georgia from 1904; this was reduced by international moratoria restricting whaling activity in the latter twentieth century. It is speculated that the extent of whaling had significant impacts on the marine ecosystem of Antarctica. We seek to find out the extent and nature this impact was and how the ecosystem has responded to the recent reduction in the intensity of whaling.

Where and how?

We will investigate these questions through the compilation of marine historical ecological records of sealing and whaling activity in the waters around the Antarctic Peninsula, through molecular and geochemical analysis of tightly chronologically constrained sedimentary and biological archives that encode information on biodiversity and ecosystem functioning, and compound-specific stable isotope analysis of well-preserved mammal and fish bone.  SEACHANGE has access to fresh sediment cores from three locations on the west Antarctic Peninsula recovered as part of the UK NERC-funded ICEBERGS project (2017-2020). These cores, from Marian Cove (King George Island), Börgen Bay (Anvers Island) and Ryder Bay (Adelaide Island), contain preserved macro- and microfossils recording ecosystem changes. We will investigate changes in biodiversity over the transitions into and out of intensive whaling using the eDNA of marine sediment and exploit an existing sclerochronology extending back to ~ AD 1900 based on crossdated Aequiyoldia eightsii bivalve shells.
 
Research into this transition poses the following questions:

• Did the removal of baleen whale species result in detectable responses in biodiversity and
  community structure?
• Have restrictions in whaling since the 1960’s resulted in the restoration of the pre-whaling
  biodiversity and community structure?