The final episode of Blue Planet II was a little different from the others. It was still a documentary about natural history, but it featured humans as the main focus rather than animals, as it was about us, how we affect our planet.
David Attenborough himself appeared on screen at the beginning of the episode, stating that at one time in history we used to think the oceans were so vast that nothing we could do had any significant effect to it, but that isn’t the case, and oceans are now under threat more than ever before.
There are billions of herring in the fjords of Norway, which attract orcas and humpback whales. But this doesn’t mean that will always be so, and in fact not so long ago there was a risk of herring being gone from there. Norwegian fisheries scientist Leif Nottestad pointed out that in the late 1960s the stock of herring was “at the brink of collapse” because of overfishing. The orcas were seen as competition for fish, so hundreds were killed. It was only after the Norweigan government started to impose restrictions that herring numbers began to recover. Orcas became a protected species in Norway in 1982, and today, a team of scientists monitor what is going on.
Marine biologist Eve Jordain spoke of what the scientists do. One thing is that they tag the orcas, using suction cups so it doesn’t leave so much as a scratch on them, and through tagging they can analyse their behaviour underwater. The fjords can still be dangerous territory for the orcas, as they are attracted to the fishing nets, seeing them as an easy way to get herring. Eve has witnessed first hand how dangerous that can be for the orcas, she once saw an orca getting trapped in a fishing net. While the strict rules are there for a good reason, they also meant that the fishermen had to wait to get permission to even open the nets to let the orca out, luckily they managed to get permission in time.
Leif also pointed out that humpback whales take less than 1% of the herring, the fishermen take less than 10%, so on balance there will be enough herring.
Sharks can also end up tangled in fishing nets. Shark biologist Jonathan Green is trying to find out where whale sharks give birth, as if they have evidence they can go to governments with it to tell them those areas should be protected.
Restrictions on whaling have also seen numbers of sperm whales increase around Sri Lanka.
Marine biologist Steve Simpson has researched noise in the seas of South East Asia, and he has found that fish actually make a lot of noise! He has listened using a hydrophone, and says that clownfish in particular are very vocal, making a lot of chirruping and popping sounds. He tested how clownfish respond using a model trout on a fishing rod. The clownfish have a specific alarm call, and individuals make distinct sounds too, in this case the female made a deep, pulsing sound while the juveniles make a popping sound.
However, when a boat went past, the clownfish were distracted, and the sound of boats is so loud it drowns out everything else. This will likely have an effect on ocean life given how increasingly widespread man-made noise is. It doesn’t have to be that way though, it is something that we can change.
There is plastic littered on beaches everywhere, and this series has shown how much of it is in the oceans too. The crew found plastic in every ocean they filmed in, even the most remote.
Lucy Quinn, of the British Antarctic survey team, stated that albatross have been in decline there for ten years. Like sea-dwelling creatures, albatross can also get entangled in fishing nets and litter, but that’s not the only problem. Albatross chicks have the ability to cough up food they can’t digest, which is usually squid beaks and fish bones, but what the chicks are coughing up now is plastic bags. While it’s good they are managing to cough it back out, some plastic may well have got into their systems. There is the very distressing sight of a chick’s bloody, rotting corpse, and its death was caused simply by swallowing a plastic toothpick. Lucy showed some of the rubbish found near nests likely coughed up by chicks. It included plastic packaging, paper wrappers and a glove. This was just from one season, and also just what they happened to find, so the real number is going to be much higher. Albatross fly for miles around trying to find food for their chicks, so someone just dropping litter thousands of miles away is having an effect.
In the USA, Dr. Leslie Hart had been investigating the deaths of young dolphins. She stated that tissue samples from the dolphins showed very high levels of toxins. She explained how this happens. Plastic which gets into the ocean breaks down into tiny fragments, and they can bond with the toxic chemicals which get pumped into the
ocean. This causes a terrible effect on the food chain from the bottom up. The toxins are eaten by plankton, which are eaten by small fish, which are eaten by large fish, which are eaten by dolphins. Over time, these toxins build up, and a mother dolphin’s milk becomes contaminated, which kills the calf.
Sometimes it can be more direct too, as we see a whale trying to eat some plastic that is floating in the ocean.
Leatherback turtles lay their eggs on dry land, but them being slow-moving leaves them an easy target for hunters. In Trinidad, Len Peters said that when he was growing up it was normal to hunt and eat turtles. However, he later read about how leatherbacks were going extinct and nobody seemed to care, so he and others decided to patrol the beach at night to protect the turtles. They faced a lot of hostility, verbal abuse, being pelted and Len said one time he was even attacked with a machete.
Ultimately, they needed the support of the villagers, so they had to find a way the villagers would benefit from having the turtles at the beach. Len encouraged tourists, with villagers as tour guides, and also went to schools to teach children about leatherback turtles. It took time, but eventually attitudes changed, and there are many poachers-turned-gamekeepers, former turtles hunters who now protect them. People give turtles a helping hand too, such as if they find eggs which are too close to the sea, they take them and bury them further up, and turtles which hatch during the day are collected in buckets to be released away from the eye of hungry birds. Len stated that all of this has seen an increase in leatherback turtle numbers here, in 20 years it’s gone from 40 turtles a night to 500 a night.
Quite an adorable moment was when David Attenborough had a tiny newly hatched turtle in his hand, then released it to the sea bidding it “Good luck, little leatherback”.
Scientist Alex Vail grew up on the island of Lizard near Australia’s Great Barrier Reef, and helped film part of Blue Planet II in 2016. He mentioned “Percy the persistent”, the tusk fish seen in ‘One Ocean’ as a favourite. But in the last few weeks of filming, the sea temperature went up to record levels, leading to coral bleaching. Alex said he had “never seen anything like this before”, and 90% of the branching corals on the reef of Lizard Island are dead. It was heartbreaking for him to see areas which he has dived in since he was a kid have died.
Professor Chris Langon demonstrated the effect to David Attenborough by pouring acid on some seashells, which dissolved. This isn’t what the oceans are like at present time, but it is heading that way, and coral reefs could be gone by the end of the century. The cause is the increasing carbon dioxide from burning fossil fuels, as carbon dioxide becomes carbonic acid when it gets to the sea. It can be stopped, if we reduce our CO2 emissions.
Finally, deep sea scientist Jon Copely talked of how fast Antarctica’s icebergs are melting, which will push up sea levels and big cities on coasts will eventually be flooded.
‘Our Blue Planet’ was an excellent episode, with an important message. At the conclusion, David Attenborough stated that never before have we had such awareness of what we do to the planet, and never before have we had such ability to do something about it, and that our future and the future of the planet depends on us. The whole series has been brilliant, it is a very well deserved biggest show of 2017, and it deserves to win awards. It has already won the Impact Award at the National Television Awards, and in Britain it has had a lot of influence in highlighting these environmental issues politically. But hopefully it will make a difference in making sure we take better care of the environment, both from high up politically, and to us as individuals, as the programme points out even small changes add up. It highlighted that there are a lot of problems, but had some optimism that we can and should do something about it.