The Magic of the Wrasse: Yvonne Sadovy on Marine Conservation and why there is reason for hope | WWF

The Magic of the Wrasse: Yvonne Sadovy on Marine Conservation and why there is reason for hope

Posted on 17 October 2012    
Yvonne Sadovy
© Yvonne Sadovy

What makes the napoleon wrasse such a fascinating species to work on?

The species is massive (it can grow to 2m) and is one of the biggest animals on the reef – an elephant of the reef - comfortable, chunky and interesting. It is gentle and curious. In places where it is not fished it will come close to divers and circle them, looking at you with its chameleon eyes - it has charisma. It is very beautiful, blues and greens and fantastic patterns around its face, which accounts for one of its many names ‘Maori’ wrasse (patterns are like the Maori facial tattoos). It is very interesting biologically with its sex change from female to male and its spawning aggregations.

Importantly, it is symbolic of a fish that is uncommon and very vulnerable to fishing but also highly in demand and very economically valuable – it is symbolic of our ability to manage such fish effectively and to balance our need to use our marine resources and the biological limits of many species (slow growth, low population replacement rates, species not common) to supply that need. For Napoleon demand is greater than supply. We need to control ourselves effectively to make sure that many reef fishes continue in healthy populations on the reef for the future and this species is a symbol and test of that challenge.

Efforts to change attitudes to seafood consumption are pitted against deeply ingrained dining traditions in China and elsewhere in SE Asia. What gives you hope that we can change this? Are there signs that we are making progress?

There is already progress and I believe that patterns, trends, even traditions can and do change over time. History shows us that, and I believe that any society can change given the right circumstances and enough education and understanding. Very encouraging are the changes we have seen in Hong Kong regarding shark’s fin, for example, which are traditionally used in weddings – many young people are opting for ‘green’ weddings with shark fin substitutes. And many people have said in public opinion polls that they would prefer not to eat endangered species but need to know more to make the right decisions. I certainly feel that the will is there to change and make more sustainable seafood choices, and especially among the young, but they need the information and are not yet getting enough. Restaurants and hotels, many of them no longer serve sharks fin or Napoleon fish.

Your work has helped the governments of Indonesia and Malaysia to introduce sustainable export quotas for humphead wrasse. Can you describe the process for translating scientific findings into information that can be turned into politically-feasible regulations?

What has to be done is to provide biologically based recommendations for sustainable export quotas for consideration by management departments or authorities in government. To do this we did surveys of populations of the fish in the field in different areas and then integrated that information, with the help of expert fishery modellers, into a fishery assessment which was assisted by FAO who also published it -- so it is widely available for inspection. The fishery model is quite complex because it was specially designed for this species and used the information we got from the field combined with other characteristics of the species such as sex change, age of sexual maturation, mortality and recruitment rates. All this information results in a population assessment that can be used to produce an export quota recommendation. To make it easy to calculate a quota we developed a special programme that any user could modify according to local conditions to calculate safely an export quota.

Once this was developed, I circulated it to the relevant authorities and workers and also gave a number of talks/workshops on it to explain. So it is quite a long process but, in summary, uses good science to survey the fish in each country (we had to develop a new survey method for the species since it is hard to survey using regular methods due to its rarity and wide ranging movements), expert fishery modelling, a user friendly programme interface and education/outreach to help understanding and to get acceptance of the approach.

Your name appears on (a movie database website),, in magazine articles, and in countless scientific journals. What skills and attitudes are required for scientists to successfully "branch out" into popular media?

I am not sure about ‘skills’ as such but certainly passion and belief that change can and must occur and an ability to communicate that directly and indirectly. Also a belief in the power of good science for good management and conservation and an ability to explain that in easy straightforward language that people can understand….in a way that I can explain to my Mum!!. A faith in human nature that most people will do the right thing if they can, and if they know about an issue, about something that is wrong and harmful or wasteful… most people will respond if they have the means to do so. So it is important to have education skills but to get that information out strategically and be persistent, one must understand that it takes quite a lot of time to change peoples attitudes, first, and then behaviour.
Yvonne Sadovy
© Yvonne Sadovy Enlarge
Napoleon wrasse or Humphead wrasse (Cheilinus undulatus), Batu Balong, Komodo National Park, Indonesia.
Napoleon wrasse or Humphead wrasse (Cheilinus undulatus), Batu Balong, Komodo National Park, Indonesia.
© Robert Delfs / WWF Enlarge

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