On the brink: 10 South American species endangered by environmental change

SSCP-DTP student Rowan Schley introduces the South American plants and animals on the verge of extinction due to climate and environmental change.

If you were to travel South America from top to tail, you would witness nearly every type of habitat present on Earth: from the steamy tropical rainforests of the Amazon, through mountains, deserts, grasslands, temperate forests and eventually the fierce seas and ice floes of the sub-Antarctic.

Unsurprisingly, such fantastic geographical diversity is accompanied by an equally impressive biological diversity: South America is home to roughly 40% of the world’s plant and animal species. However, burgeoning population growth, rapacious land clearance to make way for agriculture and climate change have taken their toll on South America’s species- according to the IUCN Redlist of threatened species, nearly 30% of species present on the continent are endangered.

To highlight this critical issue, my colleagues from the Science and Solutions for a Changing Planet DTP and I have started a digital information hub aiming to generate interest and raise awareness around some of South America’s lesser-known endangered species and the threats they face: www.endangeredsouthamerica.com. Here we present our top 10 list of emblematic South American endangered species.

1. Amazonian manatee (Trichechus inunguis)
   

   IUCN rating: Vulnerable 

Amazonian manatees are found in the murky waters of the Amazon River. They are one of three species of manatee found between South America and Africa. With a population set to decline by 30% over the next three generations, in part due to continued hunting pressure, Amazonian manatees are now threatened by habitat loss and mercury pollution from illegal goldmining.

 

2. Galapagos giant tortoise (Chelonoidis nigra)

IUCN rating: Endangered – Critically Endangered

Only found in the Galapagos Islands, 600 miles off the coast of Ecuador, Galapagos tortoise populations were historically decimated by sailors who stored them on ships to use as a source of food and water on long Pacific voyages. In the modern day, the tortoises are being edged out of their habitats by non-native goats that were introduced by settlers- goats decimate local plant life, leaving the tortoises with no food.

3. Golden lion tamarin (Leontopithecus rosalia)

IUCN rating: Endangered

Found only in the Atlantic forest of Brazil, recent relocation and captive breeding programmes have bettered the tamarin’s lot, improving their IUCN population assessment from ‘Critically Endangered’ to ‘Endangered’. However, these tiny monkeys are still under threat from agriculture-driven deforestation, which continues to fragment their forest home, severing links between populations.

4. Wonderfully-bristled Turks cap cactus (Melocactus deinacanthus)

IUCN rating: Endangered

Perhaps the best-named of all cacti, the Turks cap is only found in an 800km² area in the state of Bahia, Brazil. Existing in a series of sub-populations which are under threat by clearance for agriculture, this species is also collected from the wild by local communities due to the belief that they keep away evil spirits; as a result, this species is in decline.

5. Waved albatross (Phoebastria irrorata)

IUCN rating: Critically Endangered

Another species unique to the Galapagos Islands, this seabird uses its 2.4 metre wingspan to roam hundreds of miles hunting for fish over the Pacific Ocean. The waved albatross is threatened in part because of habitat loss on the only island on which it breeds (Española Island), due to overgrazing caused by non-native goats. However, the biggest threats to albatrosses are climate change and overfishing, which have driven the fish stocks on which these birds depend to near extinction, as well as the fact that albatrosses are frequently caught as bycatch of longline fishing.

6. Orinoco crocodile (Crocodylus intermedius)

IUCN rating: Critically Endangered

The Orinoco crocodile is the largest predator in the Americas: males can reach almost six metres long and weigh nearly half a ton. Only found in the Orinoco River in Venezuela and Colombia, these animals were hunted to near extinction during the 19^th and 20^th centuries due to the demand for crocodile leather. Nowadays pollution and collection of juvenile crocodiles for the live animal trade, in addition to hunting, have reduced the population of South America’s top reptilian predator to a mere 500 or so individuals.

7. Panamanian golden frog (Atelopus zeteki)

IUCN rating: Critically endangered

Like most other members of the genus Atelopus, the Golden Frog is critically endangered. Famous for their ‘waving dance’, these little amphibians have evolved a method of communication that doesn’t need sound: a useful adaptation to their noisy habitat among river rapids. Their population has declined by 80% over the last decade, almost certainly due to the amphibian plague chytridiomycosis: this disease is caused by a fungus and has pushed one third of frog species to the brink of extinction in the past two decades. Atelopus zeteki is almost certainly now extinct in the wild.

8. Apparition orchid (Masdevallia apparitio)

IUCN rating: Critically endangered

Only one wild individual of this vanishingly rare orchid has ever been scientifically documented- and that was in 1975. These orchids are only found in a small part of the delicate Andean ‘cloud forest’- a magical, incredibly humid forest type found around 2000 metres above sea level. Habitat destruction due to logging and climate change have irreparably damaged the forests in which the Apparition orchid was originally found, and it is unlikely to still survive in the wild. 

9. Lemur leaf frog (Agalychnis lemur)

IUCN rating: Critically endangered

A fantastic climber, the lemur leaf frog was once a common sight in the canopy of tropical forests from Costa Rica to Colombia. Unfortunately, their population has undergone a precipitous decline of over 80% in the past decade, and again the culprit is the fungal disease chytridiomycosis. Thankfully, captive breeding efforts in the US are being undertaken in order to keep these beautiful frogs safe from the decimating impact of chytridiomycosis, with a hope to eventually return them to the wild- indeed, some individuals have actually been shown to produce chemicals that provide some resistance to the infection, which could bring hope for amphibians worldwide. Find out more about Imperial research into chytridiomycosis.

10. Spix’s macaw (Cyanopsitta spixii)                          

IUCN rating: Critically endangered

Spix’s macaw is perhaps the most endangered animal on our list, and almost no hope remains that any wild individuals still exist- the last known wild bird was a male that disappeared in 2000. These parrots have an incredibly restricted natural habitat: they are only found in Brazilian riverine woodland containing the Trumpet Tree (Tabebuia aurea, known for its trumpet-like flowers), the only tree that forms large enough hollows for these birds to nest in. These riverine woodlands have been destroyed by logging, and Africanised killer bees that were released in Brazil during the 1950s now outcompete macaws for nest sites in Trumpet Tree hollows. However, captive-bred Spix’s macaws may one day be released back into the wild due to intensive conservation efforts restoring the habitat of this exceptionally rare bird.

Source: IUCN Redlist of threatened species