It's Earth Day and as the (online) celebrations continue we thought it fitting to take a virtual lap around the globe to shine a light on some of the planet’s most endangered species.

Antarctic blue whale

With a heart the size of a small car and an overall weight that can reach 200 tons, the Antarctic blue whale is the largest animal on the planet, and also one of the most endangered. Commercial whaling in the early 20th century pushed the species to the brink and by 2018 there were only around 3,000 individuals left roaming the icy waters of the Southern Ocean – just 2.5% of their levels in 1926. Encouragingly, a ban on hunting has helped the species slowly bounce back and sightings during a 2020 survey were described as “unprecedented”.

Devil’s Hole pupfish

The Devil’s Hole pupfish is quite possibly the world’s rarest fish species. These unassuming, inch-long, sapphire survivors have been clinging to life in an impossibly tiny ecosystem since the last Ice Age. In the wild, they are only found in a single aquifer-fed pool in the northern Mojave Desert where they’ve adapted to live in water with high temperatures and dangerously low oxygen levels. At least 187 are left in the wild according to a count done by a team working in the area in 2019. There are a further 50 or so being held in a refuge as part of a captive breeding programme to help save the ultra-rare fish.

Spix’s macaw
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Image © Daderot

In 2000, the Spix macaw – a brilliant blue parrot native to Brazil – was declared extinct in the wild. The bird’s eradication was largely at the hands of wildlife traffickers and the macaws became symbols of the continuing struggle to protect Brazil’s biodiversity. Now, attempts are being made to reintroduce a population of Spix macaws to Bahia state where the last known wild birds perished. The programme – spearheaded by international breeders and carrying with it a fair amount of controversy – has moved 52 birds to Bahia where they are adapting and acclimatising before their planned release later this year.

Ethiopian wolf
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Image © Nik Borrow

Eking out an extreme existence on the grasslands and rocky ridges of Ethiopia's highlands is a slender carnivore perfectly adapted to snatching rodents. Ethiopian wolves are amongst Africa's most threatened canids, with only around 500 of the animals left in the wild. As ecological specialists, the wolves are most threatened by habitat loss and the encroachment of domestic dogs, which may introduce disease into formally pristine alpine territories. Efforts to vaccinate domestic dogs against rabies and canine distemper have proven effective, but it remains to be seen how well the wolves will weather the storm.

Lord Howe Island phasmid
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Image © Granitethighs

Bug phobia? Look away now. Believed to be one of the world's rarest insects, the Lord Howe Island phasmid (or stick insect) is a whopper. Sometimes called land lobsters (for obvious reasons), the flightless, nocturnal bugs can reach lengths of 12cm. Once thought to be extinct as a result of predation from invasive mice, a tiny population was found in 2001 clinging to survival on a volcanic remnant called Ball’s Pyramid some 20 kilometres from Lord Howe Island. The remaining individuals were gathered and a captive breeding project was started at the Melbourne Zoo with the ultimate goal of reviving the population once rodents have been removed from their natural habitat.

European mink
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Image © zoofanatic

A century ago, river banks and stream-side retreats throughout much of Europe were home to European mink that used the waterways to hunt voles, amphibians, crayfish, and fish. But hunting, habitat loss and the introduction of invasive species has since decimated populations leaving them critically endangered. Much of the population decline can be attributed to the European mink's hardier distant cousin: the American mink, which was introduced to the area by fur farmers in the 1920s. A bigger and more aggressive mink, the introduced species quickly eliminated much of the competition leaving the European mink clinging to survival. Efforts continue to bring the invasive species under control and to reintroduce European mink to their historical habitat.

Sunda Pangolin

Lined with rows of armoured plates and capped with an elongated snout and an incomprehensibly lengthy tongue, the pangolin is nothing if not unique. Although they are found throughout much of Southeast Asia and are the most widely distributed of the pangolin species, Sunda pangolins are critically endangered. Like the seven other species of scaly anteaters found in Africa and Asia – these “walking pinecones” are heavily threatened as demand for their meat and scales continues to soar. A report shared with National Geographic last year shows that law enforcement seizures of pangolin scales and meat were at an all-time high in 2019 with more than 128 tons intercepted worldwide representing a 200 percent increase from five years earlier. Stricter government regulations in China along with the pangolins’ possible role in the spread of a deadly pandemic will hopefully see these numbers reduced.