conservation

According to an updated report of The IUCN Red List of Threatened Species, conservation efforts have led to improvements in the status of ten species.

This includes the recovery of the Guam Rail, a bird previously listed as Extinct in the Wild.

Despite these improvements, the IUCN Red List now includes 30,178 species threatened with extinction.

The report also finds there is increasing evidence of the negative effects of climate change. There are now 112,432 species on the IUCN Red List.

“This IUCN Red List update offers a spark of hope in the midst of the biodiversity crisis,” said IUCN Acting Director General, Dr Grethel Aguilar.

“Though we have witnessed 73 genuine species declines, the stories behind the 10 genuine improvements prove that nature will recover if given half a chance. Climate change is adding to the multiple threats species face, and we need to act urgently and decisively to curb the crisis.”

So what are the conservation success stories

The latest IUCN Red List update reveals genuine improvements in the status of eight bird species and two freshwater fishes.

Captive breeding, combined with careful management of wild populations, has been key to these conservation successes.

Among these improvements is the flightless, fast-running Guam Rail (Hypotaenidia owstoni).

It is the second bird in history to recover after being declared Extinct in the Wild, after the California Condor (Gymnogyps californianus).

Once widespread on the Pacific island of Guam, its numbers declined after the Brown Tree Snake (Boiga irregularis) was accidentally introduced at the end of World War Two.

In 1987, the last wild Guam Rail was killed by this invasive predator.

Thanks to a 35-year captive breeding programme, the Guam Rail is now established on the neighbouring Cocos Island.

However, the bird is still classified as Critically Endangered – one step away from extinction.

Other species

In Mauritius, the Echo Parakeet (Psittacula eques) continues its recovery thanks to conservation efforts. This effort included a highly successful captive breeding programme.

There are now more than 750 Echo Parakeets in the wild. With this update the species has been reclassified as Vulnerable, following its improvement from Critically Endangered to Endangered in 2007.

Two freshwater fish species – the Australian Trout Cod (Maccullochella macquariensis) and Pedder Galaxias (Galaxias pedderensis) – have likewise improved, from Endangered to Vulnerable and Critically Endangered to Endangered respectively.

Decades of conservation action have focused on establishing additional subpopulations through reintroductions and wild-to-wild translocations.

Both species face threats from invasive species and habitat destruction and degradation.

Increasing evidence of the effects of climate change

Despite these successful conservation stories, climate change has contributed to the declines of species. Some of them are several freshwater fishes and the reef-dependent Shorttail Nurse Shark.

Assessments in this update show climate change affects species by, for example, altering habitats and increasing the strength and frequency of extreme weather events.

This Red List update reveals that 37 per cent of Australia’s freshwater fish species are threatened with extinction.

Of this number, at least 58% are directly impacted by climate change.
Fish are highly susceptible to extreme droughts caused by declining rainfall and increasing temperatures.

Climate change also compounds the threat from invasive alien species, which can move into new areas as water temperature and flow change.

Native to the Western Indian Ocean, the Shorttail Nurse Shark (Pseudoginglymostoma brevicaudatum) has declined by approximately 80% over 30 years.

Simultaneously affected by unmanaged fishing and climate change, it has moved from Vulnerable to Critically Endangered.

Living only in shallow waters where it has no refuge from fishing, the shark is losing its habitat due to coral reef degradation caused in part by ocean warming.

Climate change is also threatening Dominica’s national bird, the Imperial Parrot (Amazona imperialis).

While hurricanes naturally occur in the Caribbean, their increased frequency and intensity result in high bird mortality and habitat destruction, alongside devastating impacts on people.

The species declined from Endangered to Critically Endangered after Hurricane Maria in 2017, the strongest hurricane on record to have struck the island. There are now estimated to be fewer than 50 mature individuals left in the wild.

Eucalypts assessed worldwide

All known eucalypt species worldwide have been assessed in this Red List update, revealing that almost 25 per cent are threatened with extinction.

Of the 826 eucalypts – comprising the Eucalyptus, Corymbia and Angophora species groups – 812 occur only in Australia.

As keystone species, they define the landscape of the entire Australian continent, and are culturally significant to its First Nations People.

Eucalypts including the Vulnerable Eucalyptus moluccana are the sole food source for the Koala (Phascolarctos cinereus), which has declined significantly due to loss of eucalypt habitat.

Elsewhere in the world eucalypts can be highly invasive, but in their native range in Australia they face threats from human use of land, especially agriculture and urbanisation.

This has resulted in population declines of at least 30% for 134 eucalypts, such as the Endangered Rose Mallee (Eucalyptus rhodantha), which has declined by more than 50%. Mining also threatens some restricted range species, such as the Critically Endangered Eucalyptus purpurata.

Critical habitat for conservation now remains in the areas between rivers and land, on roadside patches and in paddocks where lone trees often remain.