'My Antarctic adventure' by Dr. Bill Block (Zoology and Animal Ecology 1956-1963)

My Antarctic adventure

By Dr. Bill Block (Zoology and Animal Ecology 1956-1963)

I have always been interested in how animals, especially insects and other invertebrates, respond and adapt to extreme environmental conditions, so it was no surprise that after 13 years of University teaching and research in Makerere University, Uganda, in Cambridge and Leicester Universities that I jumped the academic ship to become a full-time researcher with the British Antarctic Survey (BAS). I had in some ways been pre-conditioned to fieldwork in cold conditions by undertaking my PhD research on the Moor House National Nature Reserve in the northern Pennines whilst at Durham (1963-66). The area has a climate similar to sea level in Iceland. Winter conditions at Moor House clearly wetted my appetite for low temperature environments.

 

Moor House in winter. Photo: Ken Park

 

I was appointed Section Head (Terrestrial Biology) in the Life Sciences Division of BAS and employed by the Natural Environment Research Council in 1976 (actually I joined on April Fool’s Day!). My duties were to provide management and supervision of a group of 8-10 biologists researching various aspects of Antarctic terrestrial biology and to undertake my own research programme. My staff included scientists appointed on contracts of 3-5 years, post-doctoral fellows and graduate students. Each of the team spent time ‘south’, i.e. working in Antarctica, most overwintering at least once. However, being married and with a family my Antarctic field work was restricted to the austral summer months. The principal Antarctic station for biological studies at that time was at Signy Island in the South Orkney Islands but also with research being undertaken on the sub-Antarctic island of South Georgia. At Signy ecological studies focussed on the animals and plants inhabiting the inshore marine environment as well as freshwater and land habitats.  The island was small (3 x 2 miles) and roughly pear-shaped; it was difficult to access by ship due to seasonal pack ice, so summer staff were usually landed in late November/early December with final relief at the end of March/early April. On one occasion, the final call could not be made due to sea ice and staff did an enforced winter (this happened to two of my group and I spent some time placating their next of kin! They were recovered in October of that year.).

 Signy Island research station 1970s - Photos: British Antarctic Survey   

 

 

Station relief by RRS John Biscoe

 

Initially our terrestrial research at Signy was to study the community dynamics and energy flow through the simple moss-dominated ecosystems found in the maritime Antarctic. The island in those days had a permanent ice cap and <50% of the island was snow and ice free during the southern summer. Only two species of flowering plants (a grass and a cushion plant) occurred there, the major vegetation being mosses, lichens and algae. Apart from seals, penguins and other sea birds, which were mostly summer visitors and were marine species, the terrestrial biota was limited to springtails (Collembola), mites (Acari), nematodes and microscopic fauna. The ecosystem models which we constructed, based on many individual projects over several years, demonstrated the fragility of these communities and the pathways of energy flow, nutrient cycling and decomposition within them. They also enabled us to study in detail predator-prey interactions and latterly, the biological and physiological adaptations of particular species to these extreme environments. These ecologically simple ecosystems would be sensitive indicators of the effects of climate change long before they would apparent in more temperate or even tropical areas of the planet.

 

Moss communities on Signy Island 

  

     Terrestrial ‘bios’ in the field on South Georgia

 

My own research concentrated on the ecophysiology of cold adaptation in the dominant micro-arthropods (springtails of 1-2 mm body length and mites of 250 mg live weight). This entailed the development and use of micro techniques to enable the respiration, feeding and growth of individuals to be measured. An early study utilised a Cartesian Diver micro-respirometer (sensitive to 10-6 µl) to determine oxygen consumption at a range of temperatures. I constructed this complex equipment in the UK, dismantled it, shipped it south and rebuilt it on station – quite a challenge! As temperature control was essential for the equipment I sat for many hours in a controlled temperature room (yes, a giant freezer) taking measurements on the instrument manually (thank heavens for many thermal layers). We were thus able to show that these small Antarctic animals had higher respiration rates than temperate or tropical species in their normal environments. The cold tolerance of these invertebrates was also of considerable interest and experiments elucidated their physiological and biochemical responses to sub-zero temperatures. A major adaptation was their great capacity to supercool (to maintain their body fluids in the liquid state below the normal freezing point). Individual mites and springtails were found to survive down to -25°C and even to -34°C before freezing and dying. Using gas chromatography we showed that glycerol and several other polyhydric alcohols and sugars were involved in such extensive supercooling. The main environmental cue to cold hardening was temperature although reduced body water through desiccation increased their survival in sub-zero conditions.

 

Antarctic mite

  

Springtail

 

During my time with BAS, I was also privileged to undertake research in Alaska, Japan, New Zealand and Siberia and in the 1990s helped to develop a UK Arctic research programme based at Ny Alesund in Svalbard. I was appointed the first Individual Merit Scientist within BAS in 1982 and received the Polar Medal from HM the Queen in 1989 for contributions to Antarctic science. I retired in 1997 and became a BAS Emeritus Fellow. Thereafter I continued research and writing and undertook three austral seasons as a guide/lecturer on Antarctic expedition ships, the latter providing very different but hugely enjoyable experiences. In 2008 I gave the Annual Fellows Lecture at St Cuthbert’s Society on Antarctica. My interest in the public understanding of science has been reflected in an active lecture and talks programme to a wide range of audiences over the past 18 years and I ran courses (Antarctic in a Nutshell, Polar Study Group) for the University of the Third Age in Cambridge for several years. More recently I have become involved with keeping honey bees, training new beekeepers and maintaining two apiaries with up to 20 colonies as well as processing honey. May (St Mary’s College) and I have three offspring scattered around the world and we live in Cambridge.

- Dr. Bill Block

Posted by Richard on Sun, 12/06/2016 - 10:02pm