BBC Blue Planet II - The Big Blue

Episode four of Blue Planet II, 'Big Blue' looks at life in the wide open ocean, many miles from land.

Find out more about how ocean and marine science at the University of Southampton is helping to understand and preserve our 'Big Blue'.

Our student blog

After each week's episode our MSci students Kieran and Elin will be updating the Exploring our Oceans blog. They will share their thoughts about the episode and relate it back to what they are learning here at Southampton.

This week Kieran talks about the pollution that is affecting even the most remote parts of the world's oceans, from his own experience of finding washing machines and a DVD player washed up on a remote beach. Elin talks about her excitement at seeing what she has learned here at Southampton come alive on screen.

We tend to think of the deep sea as being this remote alien world, but it is still inextricably linked to human life.

The open ocean is not unlike a desert with little food and protection for marine life; yet some of the ocean’s most remarkable species make this ‘big blue’ their home

Expert commentary from our staff

Research undertaken by staff here at the University of Southampton has informed much of the science that is covered in Blue Planet II.

This week Dr Antony Jensen, Associate Professor in Marine Ecology, and Dr Clive Truman, Associate Professor in Marine Ecology , share their thoughts about the Big Blue episode.

Dr Antony Jensen writes

"As ever Blue Planet 2 didn’t disappoint, showing images that are almost impossible for anyone without the resources of the BBC to achieve – long may it continue. The highlight for me this week were the resting sperm whales, such a majestic sight and only there because most nations halted whale exploitation just in time.

I continue to be delighted in the way Blue Planet links the marine biology with the other oceanographic sciences, showing how marine physics and chemistry are inextricably linked to the biological events they are filming, something OES at Southampton includes in its degrees - we have staff working across all of the marine sciences.

The final message about plastic pollution and the link with toxic chemicals was very powerful. There is a lot we don’t know about plastics in the ocean but a lot of scientists are working on the topic (a PhD student I supervise is working on plastic accumulation in filter feeders, like oysters) which should give us a much better understanding of the way plastic enters human (and other animals') diets.

I’m really looking forward to next week when the filming moves away from clear tropical waters and focuses on the more temperate seas – the trailers promise sea otters, wonderful animals!"

Find out more about Dr Antony Jensen's work and publications.

Dr Clive Trueman writes:

"Here in the British Isles, we are on the western edge of the continent of Europe. More than 17,000 km of our coastline faces the open Atlantic ocean. I’ve spent a lot of happy time standing on a western beach or cliff, looking out to the horizon and thinking about the huge watery space between me and the next land. Now I’ve turned that interest into a career studying movements of animals in the open ocean. So the Blue Planet episode on the open ocean  - ‘the Big Blue’ - excited me for personal and professional reasons.

Three things really struck me – first was the number of species filmed that pass our shores: whether the sperm whales, Portuguese men o’war, blue sharks or lantern fish, all are relatively common visitors to our shores. The programme also pointed out how little we know about some of the most charismatic animals on earth. We don’t know where whale sharks, the largest fish, give birth. The same is true for the second largest fish, the basking shark. We commonly see basking sharks in UK waters, but what they do when they leave the coastal waters and where they give birth are mysteries left to unravel.

In my research group we use chemical tools to try to understand where animals go, and what they eat. The chemistry of plankton at the base of the food web changes across seas and oceans. This signal gets passed through food into animal tissues, so we can track where a fish, jellyfish, shark, whale or any marine creature has been eating. We also use these methods to explore traceability in the global fish food market. I teach a third year undergraduate course on marine fish and fisheries, and we learn how to use these state-of-the-art tools. Undergraduate students contribute to our work, particularly through research projects in the fourth year. Recent projects have used chemical tools to reconstruct oceanic migrations in deep water sharks, blue whales, bluefin tuna and Atlantic salmon, and to test for food mis-labelling in fish and chips.

The final point made very eloquently was the problem of plastic pollution. Plastics are increasingly recognised as a major threat to ocean life, and this message was forcefully made. We are generally quite resistant to changing our habits, but small changes can have big effects. Introducing charging for single use plastic bags had a profound impact on the amount of plastic waste produced in the UK, without causing major upset. Programmes like the Blue Planet have a major role to play in raising awareness and instilling a passion for change in all of us, and could be the catalyst for real progress."

Find out more about Dr Clive Trueman's work and publications.

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