"Today I saw a new world under water. I am so lucky to have been given the mission of exploring planet Earth, although I now think it should be called planet water! I didn't have time to explore all the oceans as they cover 71 per cent of the Earth's surface. It is such a vast area that humans have only explored a tenth of it."

"My calculations estimate that 80 per cent of all life on Earth is found under the ocean surface. There are amazing marine mammals like the enormous blue whale which is longer than three London buses and has a heart as big as a car! And marine turtles, which mysteriously return to the beach where they were born to lay their own eggs, several years later. Wow!"

"My computer is having problems dealing with all the data I have collected on the fish in your oceans as there are literally thousands of different species. The swordfish and marlin are the fastest fish in the ocean, capable of reaching speeds of 120kmh in quick bursts – that's faster than the speed limit on a motorway. I had trouble keeping up with them!"

"I was amazed to find out that the ocean produces 70 per cent of the Earth's oxygen. In a process similar to photosynthesis carried out by trees and plants on land, phytoplankton, one-celled plants living at the ocean surface, use energy from the sun to convert carbon dioxide and nutrients to grow and in the process release oxygen into the atmosphere."

"The oceans also dominate Earth's weather systems by absorbing heat and redistributing it around the world. Oceans provide the main source of protein for many different species of birds, other marine wildlife and more than one billion people. Plus 90 per cent of goods sold across the world are transported via the ocean."

"Unfortunately, the way humans use the oceans has caused some problems. Some fish species, like cod, have been fished too much and are now in decline. Fishing equipment can also accidentally catch and kill other animals such dolphins and turtles. 30 million tonnes of marine life are caught in this way every year – that's the same weight as 25 million great white sharks, which if laid out in a line would stretch around the Earth three times!"

"To stop endangering the oceans and marine wildlife, humans need to stop over-fishing, and find ways to avoid catching and harming other wildlife in the process. Just like safeguarding special areas on land, such as rainforests, there also need to be protected areas in the ocean, so your wonderful range of species can be conserved."

"WWF has got the right idea! It works with partners around the world to help people use the oceans responsibly. In the UK WWF is trying to get the government to agree a law that will protect special areas of the ocean and its amazing inhabitants. I am so glad it is not too late; I'd like to visit this place again!"