Fishing is banned inside the zone, but a spillover effect has boosted tuna stocks in nearby waters, scientists have found.Marine protected areas are seen as a vital tool to safeguard the oceans, with calls for 30% of the world's oceans to be protected by 2030.As part of our build up to COP27, the BBC's Climate Editor Justin Rowlatt will be interviewing the UN's Secretary General Antonio Guterres on Wednesday 26 October and we'll be asking him your questions on climate change.If you have a question you'd like the boss of the UN to answer, you can send it to us in the following ways:In some cases your question will be published, displaying your name, age and location as you provide it, unless you state otherwise.You can also use this form to ask your question:If you are reading this page and can't see the form you will need to visit the mobile version of the BBC website to submit your question or send them via email to YourQuestions@bbc.co.uk."