Criti­cally Endan­gered Species: Beauty on the Brink

There are more than 5580 species of animals, plants and fungi listed as critically endangered by the International Union for Conservation of Nature by 2018 – critically endangered, the last category before extinct. From another perspective: Around 2850 of these species are animals. There is no doubt that we are in the middle of an extinction event, with humans being responsible in big parts. The article ‘Beauty on the Brink’ aims to raise attention for some of these bizarre and stunning creatures which are most likely to disappear from the screen, and to stress the impact of human actions on these species, both for bad and for good. There still is hope to save some of them.

Saiga Antelope – Saiga tatarica
The Saiga antelope has a distinct and extraordinary appearance, especially because of its unique proboscis-like nose. Over the past decade, this native to the arid steppes of central Asia has experienced a quick decline in population (over 80%), although it was widespread and prolific in the past. Especially male individuals have been hunted intensely because of their horn, resulting in a reproductive collapse in the aftermath. This and the loss of habitat have caused the global saiga population to drop to approx. 18,000 individuals, and it continues to decay.

Chinese giant salamander – Andrias davidianus
Being the biggest amphibian in the world with a maximum length of 1.8 metres, this primitive salamander is one of the three species in the family Cryptobranchidae. These salamanders live in large forested freshwater streams. The eggs which are laid in underwater burrows and externally fertilized are safeguarded by the male until they hatch. Due to commercial exploitation for human consumption, habitat loss and degradation these once very common creatures have experienced a decrease of population over the last few decades. Since they are incredibly rare today their recent population is unknown.

Angelshark – Squatina squatina
The angelshark – also known as the monkfish – lives on the sandy seafloor and hunts its prey by digging itself in the sand to cover up. This fish is now believed to be locally extinct in much of its range but was once very common throughout the Mediterranean and Black Seas and the Northeast Atlantic from depths of 5 to 150 metres. The extinction has been caused almost entirely by bottom trawling (a commercial fishing practice) in which a very large net is dragged across the seabed. Sadly, angelsharks and other bottom-dwelling marine animals end up as bycatch a lot although fishers intend to catch fish like cod and rockfish. There are three species in the Squatina family – Squatina squatina, Squatina aculeata (sawback angelshark) and Squatina oculata (smoothback angelshark) – which are listed as critically endangered by the IUCN actually. Five others are listed as endangered and they all are threatened by trawl fishing; either mainly or in parts.

Blue-billed Curassow – Crax alberti
The unique blue-billed Curassow from Northern Columbia is considered to be one of the rarest and most endangered birds in the world. Its blue cere (flesh area around the beak) and wattles as well as its striking crest of curled feathers is what makes this bird so special compared to other curassows. As a result of hunting and extreme habitat degradation caused by the industry and coffee, it is highly threatened by habitat loss.

Fijian Monkey-faced bat – Mirimiri acrodonta
The Fijian Monkey-faced bat is very rare and has only been found in the cloud forests on Des Voeux Peak on the island of Taveuni, Fiji, at elevations greater than 900m above sea level. In a range smaller than 100 m2, its population is likely under 1000 mature individuals. In 2005, this bat was given its own genus (Mirimiri). Only little is known about that species, including what threats it faces beyond habitat loss. Lots of species that are endemic to islands are unique because they evolved under very specific pressures and conditions. Therefore, islands happen to be a very important source of global biodiversity, but many of these species have limited ranges and populations which make them especially vulnerable to newly introduced threats.

Vaquita Porpoise – Phocoena sinus
Being the smallest whale on the planet and the most endangered, there are only 18 mature individuals remaining in the wild according to the IUCN database. It is native to the northernmost part of the Gulf of California, Mexico. With a 1997 survey estimating the population to be almost 570 individuals, the Vaquita has experienced a disastrous population decline in the last 20 years. These whales often become accidentally entangled in gillnets or fixed fishing nets, preventing them from surfacing for air – they drown and die within minutes. The use of gillnets has been banned in the range of the Vaquita for 2 years by the Mexican government in 2015 and it was made permanent earlier in 2018. The Vaquita population still continues to decline due to illegal fishing still using gillnets. There was an attempt made in 2017 to capture some Vaquita in order to breed them in captivity but this project was abandoned after the second captured specimen (an adult female) died in captivity.

Yangtze giant softshell turtle – Rafetus swinhoei
This turtle – also known as Swinhoe’s softshell turtle - is the largest freshwater turtle in the world, and there are only three left in the world. Pollution and overhunting have caused effective extinction – unimaginable that their range once stretched over Vietnam and south-eastern China. There is a mated pair in Suzhou Zoo, China, which is the only hope for that species to survive – among them, there is only one known individual existing in a lake in Vietnam. Although these two individuals have mated several times, they failed to produce any fertile eggs which is possibly caused by their age being more than 100 years. After it was discovered that the penis of the male was badly damaged in 2015, the female turtle was artificially inseminated. While the first insemination attempt failed, the Turtle Survival Alliance is working to save that species and is currently researching softshell turtle reproduction in other species to increase the chances of future inseminations.

Kakapo – Strigops habroptila
The Kakapo, which can be found in New Zealand, is the heaviest parrot on the planet. This parrot is nocturnal and flightless. It prefers a diet consisting of seeds, roots, leaves and fruits. The bird is extremely vulnerable to new, invasive predators introduced by humans due to their low reproductive rate (the breed every 2-5 years only) and their terrestrial nature. Their range – which spanned most of the North, South and Steward Islands once – has been intensely impacted by human settlement. In the 1990s, many of the remaining birds were taken to the remote Anchor Island, Little Barrier Island, and Codfish Island since their total population was so fragmented and small. In 1999, the remaining population consisted of 36 males and 26 females, of which only 50 percent were of breeding age. The Kakapo is making a comeback due to strict protections, conservation efforts and concerted breeding. The population is on the increase and the total population are about 108 estimated individuals.

West Indian Ocean Coelacanth – Latimeria chalumnae
In the Late Cretaceous, one of the only two extant species of the ancient order of lobed-finned fish (Ceolacanthiforme) thought to have gone extinct. In 1939, this species was first described near the Grand Comoro and Anjouan Islands off the coast of South Africa. The modern Coelacanth is a deep ocean nocturnal predator preying on squid and other fish species. Scientists believe that it spends the day sheltering in caves. As the West Indian Ocean Coelacanth is incredibly rare, it just got discovered – although its exact population is unknown. It is listed as Critically Endangered due to its extreme scarcity.

Giant Pangasius or Paroon Shark – Pangasius sanitwongsei
The Giant Pangasius can reach a length of almost 3 metres and happens to be a gigantic freshwater catfish from South-East Asia. The Pangasius lives in large rivers that are surrounded by rainforests and as it is a migratory species, it moves from shallower waters in the wet season to deep pools in the dry season. The migratory behaviour of that fish has been strongly impacted since development on the rivers in which it lives – especially dams – change the natural cycles of flooding and drought. They are harvested as a food source: with consumption being the main factor of their extinction, the Pangasius is also known in pet trade as the Paroon shark, and is sought after by some aquarium keepers for its long upright dorsal fin. All individuals on the market, usually juveniles, are assumed to be wild caught as there are no known breeders of this species. There is an estimated population decline of 99% over three generations due to harvesting the species.

Author: Quinn McCallum
Image credit goes to: Quinn McCallum

This article was published on Sam Puls’s blog. Sam Puls is a wildlife biologist from Belgium who would like to share stories within the wildlife biology and conservation world. For further information go to Sam’s blog and learn more about various topics in wildlife biology.

Author of the article is Sam’s friend Quinn McCallum, illustrator and biology student from Vancouver/Canada.

Sources

WildlifeIMPULSE – Sam Puls