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Meet the animals featured in the Humans episode of A Perfect Planet, their struggles and what is being done to help them.
It’s estimated that 90% of African elephants (Loxodonta) have been wiped out in the last century, mostly due to the ivory trade. Every year, 20,000 adult African elephants are killed for their ivory – that’s 55 elephants a day. But they’re also under threat from the changing climate.
Adult elephants drink over 200 litres of water a day, but with temperatures in Africa rising at an average of 0.30°C per decade since 1981, access to water supplies has become increasingly difficult. Angela Sheldrick, of Nairobi’s Sheldrick Wildlife Trust, explains: “Over the years, we’ve seen an enormous change in the weather patterns. [Leading to] greater unpredictability, the drier seasons are drier and longer.”
These periods of drought can devastate the elephant population – and the Southern African drought has been ongoing since late 2018. Consequently, many baby elephants become orphans, unable to fend for themselves.
The loss of African elephants also has far reaching consequences for their habitats. They’ve been dubbed ecosystem engineers , due to the many ways they help to shape the landscape. During times of drought, they create water holes by digging deep with their trunks, which then provides access to hydration for smaller species who can’t bore to the same depths. Even their dung is useful – not just as a fertilizer – because it spreads seeds across great distances, which helps maintain tree diversity. With elephants playing such an important role, it is vital that their decline isn’t left unchecked. Fortunately, steps are being taken.
Sheldrick and her team run a foster home for orphaned elephants in Kenya’s Tsavo East National Park, providing psychological as well as physical care, helping the young elephants overcome the trauma of losing their parents.
So far, Sheldrick’s team has been able to help release over 150 elephants back into the wild, albeit into specially managed reserves. These reserves are necessary as water supplies can be artificially topped up in the event of future periods of drought. “It is the eleventh hour now,” says Sheldrick. “We have just one home, and we as the dominant species, should take care of it, must take care of it. It’s our responsibility.”
Imagine packing your bags for a holiday, but instead of your flight taking you to the tropics, you find yourself in a much colder clime. That’s what’s happening to sea turtles, whose movements are dependent on the ocean. Their usual hatching sites are in the Gulf of Mexico, but sea turtles have been arriving further north, in Cape Cod, Massachusetts.
“The fact that they’re even here stunned so many people,” says Bob Prescott, who heads up the emergency response team. The differences in temperature results in the turtles entering a state of shock called ‘cold stunning’. Cold stunning is when, because of finding itself in colder water, the turtle suffers from a lower heart rate and a decreased level of circulation, meaning it has much less energy than it should.
But why is this happening?
Ocean currents follow a cycle. At the Earth’s poles, dense, salty water sinks to the depths, and flows toward the tropics, carrying nutrients and oxygen. When it reaches the warmer regions of the world, the colder water is heated and rises the surface of the ocean, where it flows back to the poles. This process circulates nutrients, oxygen, and heat around the planet, and regulates Earth’s climate and weather. But global warming is melting glaciers, resulting in a large influx of freshwater at the poles. Freshwater has a lower concentration of salt, so it doesn’t then sink and send cooling water toward the tropics as it should.
This disrupting, or slowing, the pattern of ocean currents is disastrous for the animals that depend on them. Waters off the coast of Boston are now warming faster than almost anywhere on Earth and this is what’s thought to be causing turtles from the tropics to swim further north than ever before for summer feeding. Which is fine… until the cold autumn waters suddenly close in.
If we can get to them within an hour of them washing up onto the beach, then we’re going to be able to save 90 to 95 percent of them.”
Finding stranded sea turtles quickly is key to their survival. As Prescott points out, “If we can get to them within an hour of them washing up onto the beach, then we’re going to be able to save 90 to 95 percent of them.” Looking out for these critically endangered species is an emergency team that monitors beaches for these stranded sea-creatures.
Once the turtles have been found, they’re rushed to the New England Aquarium in Boston, where the goal is not just to help the turtles to recover, but to deliver them safely to their desired destination. Once the turtles are back to full strength, which can take months of care, they’re flown down to the warmer climates, so they can continue with their lives.
When it comes to oceanic predators, sharks are likely to come to mind almost immediately. They play a vital role in maintaining their ecosystems… and do so simply by eating. This ensures their prey don’t become abundant, otherwise it would upset the balance of the ecosystem.
Just like the forests, the oceanic ecosystem absorbs vast amounts of carbon from the atmosphere, and the key player is also one of the smallest. Phytoplankton may be at the bottom of the food chain, but they absorb carbon. As smaller fish eat these phytoplankton, they take that carbon with them, deep into the oceans, where they are eaten by predators. And when they die, it sinks to the ocean floor. Without this regulation by large predatory fish, the ability of the marine world to be a “carbon sink” is reduced.
Yet, while sharks might seem like they’re at the top of the food chain, they’re vulnerable to a predator they cannot fight against. Humans.
Overfishing has been responsible for removing 90% of large, predatory fish. Millions of sharks are killed every year due to being caught up in fishing nets, and while some initially survive, their injuries prevent them from surviving when they’re released back into the ocean. However, while those figures paint a devastating picture, there is still hope, as conservation efforts have been shown to have a positive impact. Gabon is home to the largest network of protected marine areas in Africa, their goal to conserve marine life and protect against the damage caused by industrial overfishing.
By arresting that one single ship, we were able to save the lives of 250,000 sharks".
Over the past three years, 50 ships have been arrested for illegally catching sharks. While that may not seem like a large number, arresting just one ship can have a profound impact. Captain Peter Hammarstedt works for the conservation group Sea Shephard, which has partnered with the Gabonese government. “It’s the efficiency of these vessels that shocks me to the core…this sheer killing power of them,” he says. “Last year, we assisted the coast guard to arrest a vessel that was poaching sharks. And, by arresting that one single ship, we were able to save the lives of 250,000 sharks.”
Featured image © Nick Shoolingin-Jordan/Silverback Films 2019