In the chart we see the carcass ratio for many countries and the continent as a whole in Across Africa the carcass ratio was The overall population of African elephants has been falling in recent years. But this varies significantly across countries. In the chart of elephant populations above, you can view trends by country.
However, data is available only for the years and So even countries which show an increase in over this decade — Cameroon, for example — might have seen a decline in very recent years, which is reflected in carcass ratio data. In contrast to the African Elephant, there are fewer estimates of Asian Elephant populations.
This is more worrying because the Asian elephant is at a higher risk of extinction. We should be tracking these numbers more closely, not less. The IUCN estimates that the total population of Asian elephants has more than halved over the past century. It estimates there were , individuals in the early s; today that figure is in the range of 40, to 50, Population data over time is available for some countries in Asia: the Indian government, for example, have published estimates periodically since Where available, clicking on a country will show its change in population over time.
In India, populations have been steadily increasing since , rising from around 16, to over 27, in However, the lack of data over time for many countries makes it difficult to properly assess the health of Asian elephant populations overall.
By far the biggest threat to both the African and Asian elephant is poaching. Elephants are killed for their trunks, and their tusks. Ivory is a lucrative business. Poaching is the leading threat to all large mammals. Namibia, Zimbabwe and Angola have also managed to turn the trend. In our follow-up article we will take a look at the scale of global poaching, and what we can learn from the countries that have been successful in bringing it to an end.
The largest mammals are at the greatest risk of extinction. This has been the case since the arrival of humans, and is still true today. In this article we take a look at the status of rhino populations today, and whether they are in decline or on the path to recovery. They offer us both stories of concern and reasons for optimism. There are five species of rhino.
Africa is home to the White and Black Rhino. The remaining three — the Sumatran, Javan and Indian — exist in Asia. Some of these species have dangerously low population levels. In the table I have summarized the status of each of these species. The Sumatran and the Javan Rhino can now only be found in Indonesia. They are Critically Endangered with less than individuals left in the wild.
The Black Rhino, despite having a population in the thousands, is also Critically Endangered. It experienced a rapid decline over the 20th century as we will see later.
The Indian Greater One-Horned offers us an important success story; it has seen a significant recovery in recent decades. The White Rhino too has shown an impressive recovery. But it has a dark side: the Southern White Rhino might be doing well but the Northern sub-species is on the brink of extinction.
There are only two Northern White Rhinos left, and both of them are female. The health of these rhino populations is not just determined by how many animals are left today. The direction and pace that these populations are changing matters too. For each species I have built a time-series of populations globally and by country.
Overall, the story of the White rhino is a positive one. But this tale also has a darker side. There are two main subspecies: the Northern White and Southern White rhino.
A century ago, the Northern was much more abundant than the Southern. Now the opposite is true. In the chart we see the population trend of the Southern White Rhino. However, intense poaching by the Europeans and killings in the conversion of land for agriculture meant that by the late 19th century it was close to extinction. By there were only 20 left.
Over the course of the 20th century, severe protection of these species — particularly in African nature reserves — led to a significant and rapid increase.
Populations were restored to more than 21, Numbers grew fold within a century. Over the last few years, increases in poaching rates which we cover here have unfortunately led to another decline. South Africa is home to around three-quarters of Southern White Rhinos. You can explore population estimates by country in the chart. If the story of the Southern White Rhino is one of our greatest successes, the story of its Northern cousin must be one of our biggest failures.
The Northern White Rhino is on the brink of extinction. There are only two individuals left. Both are female. In the chart we see its demise over the second-half of the 20th century. Intense poaching, and challenges for protection during civil unrest in stronghold countries, has led to a rapid decline.
Sudan, the last remaining male died in Kenya in There are now only two female rhinos left: Najin and her daughter, Fatu. Both are guarded in a semi-wild enclosure, and have had their horns sawed off to deter poachers. Scientists are investigating ways to continue reproduction from the last females, including stem cell treatment and hybrid embryos from Northern White Rhino eggs and Southern White Rhino sperm.
Scientific innovation is now the only way to save these sub-species. Even if reproduction is successful, population numbers will be incredibly low for a long time. They will have to be closely guarded for a long time. The story of the Black Rhino is similar to that of the Northern White. The once abundant species has seen a dramatic decline over the 20th century.
Even after intense poaching by European settlers over the 19th and early 20th century, in there were still around , Black rhinos in Africa. The population reached its low point in the early s at around 2,, and have since began to recover. The number of Black Rhinos has more than doubled to around 5, Nonetheless, continued poaching has still limited population growth in recent decades.
The Black Rhino is still classified as Critically Endangered. The Indian also called the Greater One-Horned Rhino provides one success story in the restoration of wild mammals. By the midth century, there were very few Indian Rhinos left in the world. Since the mids, populations have increased nearly fold. Latest estimates, taken in , suggest there are now over 3, rhinos in the wild.
This was the result of impressive conservation efforts to reduce poaching in both India and Nepal. But Nepal also has a steady population. With only a few being spotted in recent decades, they are thought to now be extinct in Pakistan.
There were only 66 rhinos left in In recent decades it has existed in two countries: Indonesia and Vietnam. But by it had gone extinct in Vietnam. Indonesia is now its only remaining home.
Its total population has, however, increased from 50 years ago. In the s there were only 20 to 30 Javan Rhinos left in the world. From then until the s, the population approximately doubled. Over the last few decades, populations have fluctuated around 40 to Sumatran rhino Dicerorhinus sumatrensis. Like the Javan species, Sumatran rhinos are also one of the most endangered mammals.
There were only 59 left in the world in Once found in both Malaysia and Indonesia, the Sumatran Rhino is thought to be extinct in Malaysia; none have been recorded in and surveys. But in contrast to the Javan, the number of Sumatran Rhinos in the world has been falling in recent decades, from individuals in the mids to around one-tenth of that figure today.
Both Malaysian and Indonesian rhino populations have contributed to this loss. The biggest threat to rhinos is poaching. Rhino horns are still seen as luxury goods and can sell for a lot of money in illegal wildlife markets. But rhinos are not the only species at risk from poaching. But some success stories — such as the restoration of Southern White and Indian Rhino populations — shows us that their demise is not inevitable.
With the right approach we have the opportunity to turn things around. In a follow-up article we will look at the scale of global poaching, and what we can learn from the countries that have been successful in bringing it to an end.
Weighing in at over tonnes, Blue Whales are the largest animal to have lived on Earth. In fact, their size made them an incredibly valuable source of oil, meat and blubber. This fat gave us a rich fuel for energy and many other industrial uses. Human hunting has resulted in a massive decline in global whale populations.
Some have been pushed to the brink of extinction. But, as we will see, a combination of technological change, economic incentives and international policies have brought global whaling to very low levels.
While some populations are still very small, we have been successful in preserving these beautiful animals. Whaling is a practice that dates back to Medieval times; fortunately at low levels, meaning this early practice had little impact on whale populations.
While global whaling was a feature of the s, the peak of whaling in the United States was a century earlier. In the 18th and 19th centuries, whaling was a key industry in the US. Although the uses of whale oil later diversified, Americans mainly used it for lighting. As we see in the chart, US production of whale and sperm oil followed the classic inverted-U curve, peaking in the midth century. At this point petroleum oil had been discovered, and kerosene — which was cheaper than whale oil — began to replace it in lighting.
As whale hunting became increasingly unprofitable, production soon declined. Towards the end of the s, new technologies were being developed that could catch whales in much larger numbers. Rather than the classic sail- or oar-powered boats that the Americans had been using, the Norwegians developed mechanized, steam-powered vessels with cannons and harpoons. This made whaling much more efficient. Not only could we catch more whales, it also allowed us to catch species — like Blue and Fin Whales — that were too fast for our old technologies.
It had a dramatic impact. Whale populations fell by two-thirds in just over a century. In there were around 2. By there were only , left. Not all species were impacted equally. Some of the largest — the Blue and Fin Whale in particular — were prime targets.
This meant that the decline of total biomass of whales over this period was even greater. We see this discrimination towards particular species in the chart. All species declined, but the extent was wildly different. Its populations fell from , to just 5, A reduction of Both demand and supply rocketed. Whale oils were initially used for lighting, but their market soon expanded. Sperm oil is special because it maintains its lubricating qualities at very high temperatures — this made it a vital ingredient for machinery, engines, guns and watches during the Industrial Revolution.
Advancements in cosmetics and food chemistry meant that its by-products were soon used for soaps, textiles, and even margarine. Ambergris — a substance found in the intestine of sperm whales — was, and still is, used to make perfume. You will find it in the luxury perfume, Chanel No. Whales made it into the fashion industry too. In the chart we see how this rising demand for whale products affected hunting rates across the world.
This shows the number of whales killed each year, from onwards. For decades, tens of thousands of whales were killed each year.
Only World War II gave these animals some reprieve — notice the drop in kills during the earlys. In fact, a number of countries formed the International Whaling Commission IWC in to work out how to manage international whaling stocks.
By the midth century, many species were pushed to the brink of extinction. By the midth century, the prospects for whales was looking bleak. And yet, the world managed to turn things around. In the chart we see the number of whales killed per decade. We see a gradual rise over the first half of the century — with the exception of the war-stricken s — with whale catch reaching its peak in the s. But, we see a decline since then.
What caused this? There were a number of factors at play. By the s, whale populations had become increasingly depleted — this scarcity had an impact on the economic incentives to hunt them. Whales were becoming harder to find and catch. Technological advances also meant that substitutes for whale oil and bone in the cosmetic, food and textile industries were becoming cheaper and more accessible.
The whaling industry was losing its profitability. There was another massive policy change in the s. More and more countries were becoming members of the International Whaling Commission. In the map we see the timeline by which countries joined the IWC. After many decades of failed quota agreements, the IWC agreed to a global moratorium. This made commercial whaling illegal, with only a few exceptions. These countries typically hunt species that are not considered to be critically endangered.
Some species will still take many decades to recover. Populations of North Atlantic right whale, the Arctic bowhead, and the Pacific blue whale are still critical.
Yet the story of whaling overall is a conservation success: an animal that was once in high demand across the world has been saved from extinction through substitution and international cooperation. Many species are in a similar position to whales in the s. But the decline of whaling should give us hope that we can turn things around once again. Explore the diversity of wildlife across the planet — how many species are in each group, and where they live.
See how wild mammal populations have changed over time; where they live today; and where they are threatened with extinction. Explore the diversity of birds across the world; how many species have gone extinct; and how populations are changing.
Explore the distribution of coral reefs across the world and how they are changing from human pressures. The Living Planet Index is one of the most-common biodiversity metrics. Hunting is one of the largest threats to wildlife. See how poaching rates and trade has changed over time, and across species. According to the media publication, Milo said he is opting for a mostly vegetarian diet due to the negative environmental impact of meat production.
When I do a puzzle with my daughters, there is usually an elephant next to a giraffe next to a rhino. But if I was trying to give them a more realistic sense of the world, it would be a cow next to a cow next to a cow and then a chicken. Another report, released last year, said that within the past 50 years alone , an estimated half of animals on Earth were lost to industrialization.
However, the large proportion of livestock being farmed for food is an unsustainable method of feeding the world, according to a report released earlier this month. It said the food industry could feed a vastly greater amount of people by cultivating plant crops rather than raising livestock.
Get exclusive access to delicious plant-based recipes, sustainable living guides, and food news hot off the press. But if I was trying to give them a more realistic sense of the world, it would be a cow next to a cow next to a cow and then a chicken. Viruses alone have a combined weight three times that of humans, as do worms. Fish are 12 times greater than people and fungi times as large.
The researchers calculated the biomass estimates using data from hundreds of studies, which often used modern techniques, such as satellite remote sensing that can scan great areas, and gene sequencing that can unravel the myriad organisms in the microscopic world. They started by assessing the biomass of a class of organisms and then they determined which environments such life could live in across the world to create a global total.
They used carbon as the key measure and found all life contains bn tonnes of the element. The researchers acknowledge that substantial uncertainties remain in particular estimates, especially for bacteria deep underground, but say the work presents a useful overview.
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