Cape Town CNN  — 

From above, it looks like a vast oil spill spreading across the ocean. It’s been called the “Greatest Shoal on Earth” and it’s one of the planet’s biggest migrations in terms of biomass.

Along South Africa’s east coast, between May and July, billions of spawning sardines travel north towards Mozambique. They are pursued by predators ranging from sharks to dolphins, whales and even humans.

Before the Covid-19 pandemic, the annual “Sardine Run” would attract tourists from across the globe. But this year, South African free diving champion Beth Neale was one of the few people who witnessed this phenomenon.

Armed with a GoPro and 360-camera, she swam beneath the big black slick of fish to film the incredible variety of marine wildlife it attracts. She believes her footage can help people appreciate how the ocean ecosystem depends on seemingly insignificant fish like the sardines.

“I know through seeing the beauty of the sardine run and the underwater world, people start to understand how connected everything is,” Neale tells CNN. “From seeing a fish as something that’s just a food source to seeing a fish as its integral role in the whole marine food chain and how that fish supplies so many marine animals.”

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A recent study in the South African Journal of Science shows changing weather patterns caused by the climate crisis may threaten the sardine run. It also means the sardines are migrating later in the year, which can cause food shortages for animals like the sharks that feed on them.

Protecting the oceans

As well as climate change, shoals like this are threatened worldwide by overfishing. The UN says one third of commercial fish species are being over-exploited.

The sardine run passes through some of South Africa’s marine protected areas (MPAs), where fishing is restricted by law, giving sea life a chance to recover. Neale has been diving these waters for years and says she can see a significant difference between the areas that are safeguarded versus those that aren’t. “The most amazing thing about the ocean is once you implement a marine protected area, you can see the change really, really rapidly,” she says.

Jean Tresfon
South African Steve Benjamin is an underwater photographer based in Cape Town, which he refers to as a "Mecca" for marine wildlife. "Revealing and promoting the wealth of life around South Africa has developed into a life quest for me," he tells CNN. Benjamin, who has a degree in zoology, hopes that his underwater images will open people's eyes to the value of marine protected areas -- spaces set aside for nature conservation.
Steve Benjamin
Benjamin has been capturing images of South Africa's marine environments and wildlife since 2008. He took this photo of a red roman in the De Hoop Marine Protected Area, along South Africa's eastern coast. These reef fish are found nowhere else in the world and are especially vulnerable to overfishing. As of 2019, South Africa had declared 42 marine protected areas (MPAs), totaling 5% of the country's ocean territory.
Steve Benjamin
This Cape bream was photographed in the kelp forests around Cape Town, which are part of the Table Mountain MPA. Benjamin explains that marine protected areas help to manage the environment, keep marine ecosystems working properly and protect the range of species living there, helping people to benefit from the ocean.
Steve Benjamin
Benjamin captured this image of a short-tail stingray gliding over an offshore kelp forest on Alphard Banks in the Western Cape, which was declared a MPA in 2019. To get this shot, he traveled 2.5 hours offshore by boat and dove into a kelp forest where rays were hovering above him. One particularly curious stingray made its way down towards him and that's when he snapped this image, using a Nikon D70 camera in a Subal underwater housing.
Steve Benjamin
This green turtle was photographed while undergoing rehabilitation at a Durban aquarium before being released. Over the course of his career, Benjamin has photographed hundreds of turtles all over Africa -- from Madagascar to Tanzania and his native South Africa. He especially loves this photo because it shows that while many marine animals are negatively impacted by human activity, humans are also crucial in caring for and protecting them.
Steve Benjamin
Blue sharks visit the offshore waters of South Africa. In 2019, South Africa added its first large offshore reserves, located around 50 kilometers out to sea, to its list of marine protected areas. Benjamin says these MPAs help to ensure that offshore ecosystems continue to sustain South Africa's fisheries, buffer us from climate change and inspire us to further explore the secrets that lie beneath our blue horizon.
Steve Benjamin
A Cape clawless otter enjoys the abundance of food in Cape Town's False Bay. Benjamin says that MPAs allow top predators, like this otter, to thrive in a healthy ecosystem.
Steve Benjamin
MPAs have also helped bolster whale populations. In 2017, scientists discovered that humpback whales congregate off South Africa's west coast to feed in tight groups numbering in the hundreds, called "super-groups," Benjamin says. These whales have recently returned to areas from which they were previously exterminated.
Steve Benjamin
Scientists fit a satellite tag to a tiger shark, to track its movements. Benjamin explains that this is done to understand where these animals spend their time and where they are likely to come into conflict with humans or get caught by fishermen. This information helps to support and inform how MPAs are managed and designed, he says.
Steve Benjamin
Cape fur seals, which are often referred to as the "dogs of the ocean," play in the kelp forest around Duiker Island in Hout Bay. These animals were once threatened, but today their population has risen to around two million. Before the pandemic, they had become a popular tourist attraction around Cape Town and when Benjamin isn't taking photographs, he runs seal snorkeling expeditions.
Steve Benjamin
Southern right whales give birth in the shallow bays along the Southern Cape coastline of South Africa. In Hermanus, an MPA, restricted boat access gives these gentle giants a chance to raise their young in peace. After obtaining a special permit, it took Benjamin a week to get this shot. Eventually a mother and calf made their way towards the boat and the calf raised its head for the camera at just the right moment.
Steve Benjamin
Through years of diving, Benjamin has seen how MPAs aim to preserve entire ecosystems, from seaweed to sharks. This photo shows a sevengill shark, which Benjamin says were once common in the Millers Point MPA in False Bay. But he tells CNN, "(they) have moved off, possibly due to disturbance and predation by orcas."
Steve Benjamin
Across South Africa, fishermen rely on their catch to supplement their diets -- especially in rural and underdeveloped areas like Mdumbi, in the Eastern Cape, where this photo was taken. Fishermen also benefit from marine protected areas, as Benjamin says, "MPAs are like biological bank accounts and we can all live off the interest they provide."
Steve Benjamin
"Humanity has not always treated the ocean with the respect it deserves," he adds. "Throughout history, we have risked the potential bounty of food for consumption or carelessly emptied waste into its waters, hoping it will disappear." Benjamin believes that law enforcement is critical to ensure that people adhere to respecting MPAs. In this image, fishery inspectors check the catch of fishermen near Tsitsikamma, Eastern Cape.

South Africa is home to 42 MPAs , which aim to protect wildlife for the benefit of both nature and people.

Prior to 2019, only 0.4% of the country’s ocean territory was protected, but that has recently increased to 5.4% with a target of reaching 10%, says marine biologist Kerry Sink, who has played an instrumental role in advising the government on this expansion.

“The reason why it’s really important to manage our fisheries well is because if we do that, we can fish forever,” Sink tells CNN. “In a world with increasing pressure and increasing industrialization of the ocean,and in a time of climate change where there’s even more uncertainty, we need to do everything that we can to have healthy oceans and healthy fish stocks.”

Neale wholeheartedly agrees. “You protect what you love,” she says. “The ocean is what I truly love the most.”

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