Exeter Marine Podcast – Arctic Terns, Basking Sharks; Bluefin Tuna, with Dr. Lucy Hawkes

 

In this episode we talk to Dr. Lucy Hawkes about a number of her research areas including arctic terns, basking sharks and bluefin tuna. Listen out for a story about a mysterious tuna tag as well.

 


 

About our guest: Dr. Lucy Hawkes 

Lucy is a physiological ecologist, whose work focuses on the costs and drivers of migration in animals (vertebrates and invertebrates) using emergent technologists such as satellite telemetry, heart rate logging, accelerometry and metabolic rate measurements. Lucy uses technical approaches including biologging, spatial ecology, remote sensing and respirometry to make empirical measurements that help in the understanding of amazing migratory performances. Lucy’s work has also investigated the impact of external forcing factors, such as climate change and disease ecology on migration and breeding ecology.

 

This slideshow requires JavaScript.

Above: Dr. Lucy Hawkes, Dr. Matt Witt and the team working with basking sharks. Photo credits: Nic Davies

 


 

Topics discussed:

  • Lucy’s experience as a National Geographic Explorer.
  • Tagging and studying bluefin tuna.
  • The long distance migrations of arctic terns.
  • Studying basking shark behaviour.
  • Breaching basking sharks.
  • The journey of a mysterious tuna tag (pictured right).

 

 

 

 


 

Basking shark videos

 


 

Resources:

 


 

Episode and show notes produced by Ben Toulson and Katie Finnimore.

Check out other episodes of the podcast here.

You can subscribe on most podcast apps, if you’re feeling kind please leave us a review!

#ExeterMarine is an interdisciplinary group of marine related researchers with capabilities across the scientific, medical, engineering, humanities and social science fields. If you are interested in working with our researchers or students, contact Emily Easman or visit our website!

 

 

My Exeter PhD: Understanding marine citizenship, Pamela Buchan

To make change happen, we need to understand what motivates people to act. Today we hear from Pamela Buchan, PhD student with the University of Exeter who is studying Marine Citizenship.

Words by Pamela Buchan, PhD researcher at University of Exeter and elected councillor with Plymouth City Council.

There is a new environmental movement sweeping the world, spearheaded by Greta Thunberg, and carried forward by young people who are demanding a better future. Climate change concern in the UK is polling higher than it ever has before, and even the British government has caught wind of the desire to reduce plastic consumption. The global climate strike saw 7.6 million people around the world take to the streets. People are protesting, signing petitions, switching to electric vehicles, changing their behaviours, and making more sustainable choices to create cleaner seas and a sustainable future for everyone. This is environmental citizenship in action.

School children strike for climate, 20th September 2019. Credit: Pamela Buchan

 

Global climate strike in Plymouth, 20th September 2019. Credit: Pamela Buchan

For three years I’ve been investigating the idea of marine citizenship in a bid to better understand what drives people to become active marine citizens, what it is about the sea that is particularly motivating, and how do policies and legislation work to promote or hinder marine citizenship actions. Actions that benefit the marine environment are likely to benefit the climate also, and this might be a gateway to broader environmental citizenship. As someone who grew up in the middle of the moors with little access to the sea, it was the desire to be near the sea that first took me to Newcastle University to study marine biology and later relocate with my family to Plymouth to benefit from the ocean culture in this city and region. For me, it’s all about the sea, but what about others who are active in marine environmentalism? Does the sea as a place occupy others’ hearts in the same way?

Greta Thunberg departs from Plymouth for the US, aboard the carbon neutral Team Malizia yacht, on 14th August 2019. Credit: Pamela Buchan

Research around creating environmental citizens is often focused on environmental education and awareness raising. If people understand, are aware, and know what to do, then they’ll crack on and do it, right? This leads to lots of research investigating the perceptions, attitudes, and knowledge held by the general public, which then provides the basis of programmes to increase pro-environmental behaviours. See, for example, the list of research informing the DEFRA Framework for Pro-Environmental Behaviours, which probably explains why the goal for reaching the “unengaged and unwilling” is to: “encourage and support more sustainable behaviours through a mix of labelling, incentive and reward, infrastructure provision and capacity building (e.g. through information, education and skills).” (Emphasis mine.)

Research contributing to DEFRA Framework for Pro-Environmental Behaviours, 2007.

Undoubtedly, knowing effective ways to act is an important part of environmental citizenship but clearly it is not the whole solution. If we only ask questions about what people know, then we will only find answers that relate to knowledge. And despite many attempts at environmental education, carbon emissions continue to rise, oceans continue to be exploited and polluted, and even littering and flytipping seem to be on the increase. Knowledge isn’t changing people’s behaviours towards the environment so we need to look more deeply and holistically for other factors.

One field to turn to is environmental psychology and theories around values and identities. Social psychologist, Susan Clayton, has developed a theory that environmental activists share an environmental identity. Other researchers have argued that environmentalism is based on self-transcendent values, such as benevolence and universalism (e.g. Stern et al. 1999 and many since). We must acknowledge that not all people hold strong environmental identities or altruistic values, yet there is a lack of evidence exploring how different kinds of people can be motivated into environmental citizenship. If we are to tackle the environmental problems of today, we need at the very least for all people to be open to policy changes.

Enjoying the sea. Credit: Pamela Buchan

My PhD[1] seeks to fill this gap, specifically for marine citizenship. I set out to create space in my research design that would accommodate all findings relevant to this idea. Though my research design draws on theories from environmental psychology, human geography, and environmental law, my use of mixed methods allows me to piece together these theories with emergent findings. In my research, I surveyed, interviewed and shadowed active marine citizens, using psychological metrics and open ended interviews side by side. I found my population through case study marine groups and the national citizen science programme Capturing Our Coast and, using my survey data, I purposefully selected as broad a range of interview participants as I could. Selecting respondents with low self-transcendent values, higher self-enhancing values, a wide range of demographic variables, and as wide a range of relationships with place as was possible from the survey population.

My goal was to find the stories of people who are different. How do people who don’t fit the existing research models come to be active marine citizens? In my final year, I am still analysing my data and pulling it all together, but I have some surprising and tantalising headline findings emerging. The data has been telling me that marine citizenship is not so much a set of pro-marine environmental behaviours, but rather such behaviours are an expression of a marine identity. This marine identity is triggered, developed, or maintained, through sensory experience of the sea that promotes attachment and dependency. It seems that for marine citizens, as with myself, it is the sea itself which motivates citizenship. But there is diversity in marine identity, with people’s values shaping their motivations and types of actions they participate in. It does seem that people with a range of value sets can and do become active marine citizens via their connection to the sea.

There is already research showing that aligning climate change messaging towards specific values will encourage concern in those who are previously unconcerned (see for example Myers et al., 2012). My research points to the potential of the sea as a means of public engagement, which is arguably exemplified in real time through the ‘Blue Planet effect’ in which people have been spurred to reduce single-use plastics. If the experiential qualities of the sea can help people develop a marine identity and, from that, a willingness to perform pro-marine environmental behaviours, then it may be a valuable pathway towards improved ocean and climate health.

South Milton, Devon. Credit: Pamela Buchan

[1] ESRC funded on the interdisciplinary Environment, Energy and Resilience pathway, now known as Sustainable Futures

Further reading:

Read more about the psychological aspects of marine citizenship in my paper Citizens of the Sea: defining marine citizenship, delivered at the International Conference on Environmental Psychology, 2019.

I’ll be presenting on my PhD research at the Coastal Futures conference in London in January 2020.

Follow Pam on Twitter.

#ExeterMarine is an interdisciplinary group of marine related researchers with capabilities across the scientific, biological,  medical, engineering, humanities and social science fields.

Find us on: Facebook : Twitter : Instagram : LinkedIn  

If you are interested in working with our researchers or students, contact Michael Hanley or visit our website!

My Exeter PhD: Camouflage helps brightly coloured chameleon prawns to survive in the rock pools

Camouflage is vital to an animals survival, blending in to the background can stop you being spotted by predators or conversely, allow you to sneak up on your prey. But how do animals that live in highly variable environments like rockpools, where the surrounding plant life and available hide-y holes can change from one tide to the next, stay camouflaged? One option to has a variety of colour morphs like the chameleon prawn found in UK rockpools, but what happens if you suddenly find yourself in a pool predominately full of green seaweed when you are bright red?

University of Exeter PhD student Sam Green tells us about his new paper with the Sensory Ecology Evolution Group, working to understand the drivers of variation in the chameleon prawn colour variation.

Words by Sam Green, PhD Student, University of Exeter.

Key findings: Brightly coloured and aptly named chameleon prawns (Hippolyte varians) combine impressive changes in colour with behavioural preferences for particular seaweeds to survive in their rock pool habitats.

Here in Cornwall we are lucky to have easy access to incredibly diverse rock pools around our coastline that are teaming with wildlife. One fascinating species dwelling amongst the seaweeds close to the low tide line is the chameleon prawn (Hippolyte varians). An apt name for a species that is highly variable in appearance and found in forms ranging from vibrant red and green colours to varying degrees of transparency and patterning1,2. But what is driving this remarkable variation?

 

Chameleon prawns (Hippolyte varians) are found in an incredible diverse range of vibrant colour forms in UK rock pools.

Rock pools are extremely beautiful and colourful environments but they are challenging to live in.  Every day the tides’ ebb and flow, which changes the availability of submerged habitat as well as the varieties of predators that range over the rock pools looking for an easy meal. Could this variation in colour help prawns to avoid the interests of hungry fish? One possibility is that prawn coloration provides camouflage against their seaweed substrates. But how can they maintain this camouflage when the rock pool environment is so variable and always changing?

Natural habitats comprise many potential background colours, posing a challenge for any animal that relies on camouflage – such as this array of seaweeds in a rock pool.

One remarkable camouflage strategy that might be used is for an animal to change body coloration itself. This is surprisingly common in the natural world with the duration of change ranging from a few seconds to weeks and months3. The well-known masters of this strategy include octopus and cuttlefish, where many are capable of swift changes to their coloration enabling them to quickly tailor their camouflage to the surroundings4. Might chameleon prawns also utilise colour change to better match their surroundings?

In our research we have focused on green and red chameleon prawns and their seaweed substrates, the green sea lettuce and red dulse. We brought prawns and seaweed into the lab and housed the prawns on seaweed of opposing coloration. Then, analysing coloration of prawns and seaweed from the perspectives of predatory fish visual systems, we measured changes in colour in relation to camouflage.

 

Chameleon prawns were kept individually on seaweed of mismatching coloration in the lab to induce colour change.

Prawns have an excellent level of camouflage against their associated substrate types. They are also capable of impressive, if somewhat slow, colour changes that drastically improve camouflage against the previously mismatching seaweed over a number of weeks. So the prawns can change colour, but it’s clearly too slow to maintain camouflage when swimming around the rock pools. The seaweeds that comprise the ‘algal forests’ of the intertidal zone vary with the seasons5. These slower colour changes probably enable prawns to capitalise on seasonal seaweed shifts, whilst still benefiting from the protection of camouflage. If this is the case, how do the prawns maintain camouflage on a day-to-day basis?

Examples of the remarkable changes in colour displayed by green and red prawns over the 30 day experiment.

Animals often improve their camouflage through behaviour, such as choosing appropriate backgrounds that maximise their camouflage6.  Again using the same two species of seaweed we tested the behavioural preferences of green and red chameleon prawns. The prawns display strong behavioural preferences for selecting a background that best compliments their own coloration. So, whilst colour change may be of no use if a passing wave were to dislodge a prawn from its chosen camouflaged perch, they are able to quickly rectify the issue by swimming to the nearest patch of suitable seaweed.

The behavioural choice chamber used in our study. Here a red prawn chooses between suitable seaweed backgrounds.

The act of remaining camouflaged is rarely as simple as it first appears. The incredible variation in body coloration displayed by chameleon prawns enables the highest level of camouflage against particular seaweed backgrounds. On top of that the prawns display clear adaptations for remaining obscured in their environment, despite the challenges presented by their rock pool existence. For the chameleon prawns, our research shows that perhaps the best way of maintaining camouflage in the face of variation is to have a suite of strategies to suit the occasion.

Chameleon prawns are extremely well camouflaged against their favoured seaweed backgrounds. As seen here with green prawns and green sea lettuce.

Read the paper here

You can follow Sam on Twitter: @saunteringsam and Instagram: @saunteringsam

You can also keep up to date with the Sensory Ecology and Evolution Lab on Instagram: @See_research_lab and Facebook

References:

  1. Gamble, F. W. & Keeble, F. W. Hippolyte varians: a Study in Colour-change. Q. J. Microse Sci. 43, 589–703 (1900).
  2. Keeble, F. W. & Gamble, F. W. The colour-physiology of Hippolyte varians. Proc. R. Soc. London 65, 461–468 (1899).
  3. Duarte, R. C., Flores, A. A. V, Stevens, M. & Stevens, M. Camouflage through colour change : mechanisms , adaptive value and ecological significance. (2017). doi:10.1098/rstb.2016.0342
  4. Hanlon, R. Cephalopod dynamic camouflage. Curr. Biol. 17, 400–404 (2007).
  5. Dickinson, C. British Seaweeds – The Kew Series. (Eyre & Spottiswood, 1963).
  6. Stevens, M. & Ruxton, G. D. The key role of behaviour in animal camouflage. Biol. Rev. (2018). doi:10.1111/brv.12438

#ExeterMarine is an interdisciplinary group of marine related researchers with capabilities across the scientific, biological,  medical, engineering, humanities and social science fields.

Find us on: Facebook : Twitter : Instagram : LinkedIn  

If you are interested in working with our researchers or students, contact Michael Hanley or visit our website!