Restoring habitats key to fighting extinctions

At BirdLife, science underpins everything we do. As the official Red List Authority for birds, we regularly reassess the global extinction risk of all the world’s bird species, to help draw attention to those at highest risk and to highlight where conservation action is working.

Our 2025 Red List update includes reassessments of 1,360 bird species and completes our eighth comprehensive assessment of all bird species. Involving thousands of experts over nine years, 1,256 (11.5%) of the 11,185 species assessed are globally threatened. Overall, 61% of bird species have declining populations – an estimate that has increased from 44% in 2016. 

Dr Ian Burfield, BirdLife’s Global Science Coordinator (Species) and Bird Red List Authority Coordinator, said:

“That three in five of the world’s bird species have declining populations shows how deep the biodiversity crisis has become and how urgent it is that governments take the actions they have committed to under multiple conventions and agreements.”

This update also confirmed the tragic news of the extinction of the Slender-billed Curlew, a migratory shorebird that once bred in Western Siberia and wintered around the Mediterranean. This is the first known global bird extinction from mainland Europe, North Africa and West Asia.

Worldwide, the most prevalent cause of bird population declines is habitat loss and degradation, driven especially by agricultural expansion and intensification, and logging – the foremost threats to birds at risk of extinction. While reducing the rate of habitat loss is essential to protect birds, restoring degraded habitats is another important piece of the puzzle.

Read on to find out more about some of the species that have been reclassified as part of this update and go on a round-the-world trip to discover what our Partners are doing to help.

Eradicating goats from Guadalupe Island

Let’s start our journey in Mexico. We’ve just arrived on Guadalupe Island, a Biosphere Reserve and a Key Biodiversity Area located 250 km west of Baja California. Surrounded by a rugged landscape of volcanoes, we can hear the roars of Northern Elephant Seals in the distance.

Despite its remoteness, some of the island’s native bird species have struggled due to the introduction of goats in the 19^th century. The Guadalupe Junco, an endemic songbird, was once among the island’s most abundant birds, but declined greatly as the goats’ intense grazing denuded the cypress forests that the junco relies on for its survival. By the 1990s, only 50–100 individuals were thought to remain, and the species was considered Critically Endangered.

In 2007, as part of a major programme to restore Mexico’s islands, a project was completed to eradicate all the feral goats from Guadalupe. Their removal led to the considerable recovery of the native vegetation, including the cypress, and by 2016 the Guadalupe Junco population was estimated at 75–250 mature individuals, qualifying as Endangered. Today, further increases mean there are 330–800 mature individuals, and the species is now assessed as Vulnerable, as it continues to recover because of this habitat restoration.

Supporting sustainable agriculture in Sierra Leone

Hop on board, we’re heading to Sierra Leone! We have just entered the Gola Rainforest National Park, one of the last remaining intact parts of the tropical Upper Guinean forests in West Africa. Tall trees surround us, and we suddenly hear a strange cackling “wha-o wha-o wha-a-a-aw whaaaw” sound. A large black hornbill with a patch of light blue around its eyes and a large casque on the top of its head is staring at us.

The Black-casqued Hornbill is heavily dependent on the forest for its survival. Unfortunately, outside of the national park and some other protected areas, the trend is not good. Data from Global Forest Watch reveal significant forest loss in this hornbill’s range in recent years, contributing to its status being elevated from Least Concern to Near Threatened this year.

Deforestation in the region is often linked to forests being turned into agricultural areas. In Sierra Leone, our Partners, the Conservation Society of Sierra Leone and the RSPB, are tackling this issue through a REDD+ (Reducing Emissions from Deforestation and Degradation) project. By working with local communities, the project aims to advance sustainable agriculture and agroforestry practices.

The project supports more than 2,500 farmers who have been trained and provided with the equipment they need to grow forest-friendly cocoa. But it also targets another growing threat faced by the Black-casqued Hornbill: poaching. The development of an international illegal market in hornbill parts in recent years is putting even more pressure on the species. The REDD+ initiative is funding direct protection of the forest through ranger patrols, which has the potential to alleviate the pressure on hornbills and on other species inhabiting this precious ecosystem.

While most Asian hornbill species are protected through the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), no African hornbills are currently listed. BirdLife supports the recent proposal to offer more protection to these species, including Black-casqued Hornbill, and hopes it will be adopted at the upcoming CITES CoP in Uzbekistan in November.

A tale of two islands in the Indian Ocean

Time for a quick stop in Madagascar! Tropical forests are an important habitat for many bird species in the country, but these ecosystems are under intense human pressure on the island. Slash-and-burn agriculture and uncontrolled fires are among many reasons for the concerning decline of forest habitat in recent years, which has led 14 endemic forest bird species to be uplisted to Near Threatened and three to Vulnerable.

Vony Raminoarisoa, Executive Director of ASITY Madagascar (our Partner in the country), said:

“Even if almost all of these 17 species live in Madagascar’s protected areas, this change in conservation status means that greater conservation efforts are needed, particularly in terms of strengthening research on these species to prevent further decline.”

One such species is the Schlegel’s Asity, whose males have vibrant blue and green patches on their faces. Only found in intact native forest in northwest Madagascar, this species’ population is currently thought to be declining at a rate of more than 30% per decade due to rapid deforestation within its range, and hence now qualifies as Vulnerable.

Despite this bleak news, one aim of the IUCN Red List update is to highlight negative trends so that conservation actions can be put in place for the species that need them the most. And we have a proven antidote to habitat loss: nature restoration!

Let’s cross the Indian Ocean for our final stop and head east of Madagascar, towards the Mascarene Islands. Our destination? One of the world’s most remote inhabited islands: Rodrigues. Located about 600 km east of Mauritius, Rodrigues lost 10 of its 12 endemic bird species in the past, due to forest clearance for cultivation, grazing by feral livestock and introduced predators. The two remaining bird species also came close to extinction, with only 5 or 6 pairs of Rodrigues Fody in 1968 and only 8 or 9 pairs of Rodrigues Warbler in 1979. As recently as 2012, the fody was assessed as Vulnerable and the warbler as Endangered, although since then both species have been listed as Near Threatened.

The gradual improvement in their status reflects the restoration efforts led by our Partner, the Mauritian Wildlife Foundation (MWF), to recover and expand native woodlands on Rodrigues. So successful have these efforts been that the fody’s population has boomed to approximately 20,000 individuals and the warbler’s to around 25,000 birds, with both species now found in most native forests across the island. As a result, both species are now considered Least Concern, showing what is possible through partnership and perseverance.

Dr Vikash Tatayah, MWF Conservation Director, said:

“It’s wonderful to see the rebound of two birds that teetered on the path of extinction some 60 years ago and have bounced back to become fairly common birds in built-up areas and backyards, and almost anywhere with suitable forests, including secondary forests, on Rodrigues. Especially that the comeback for these Rodriguan species did not involve captive breeding, releases, supplementary feeding, disease and predator control, genetic management and detailed studies that their Mauritian bird counterparts have required.

The recoveries of the Rodriguan passerines have rested purely on habitat restoration and protection and show that the return of passerines from near-extinction to Least Concern is possible, bringing a glimmer of hope for passerines worldwide. It is above all a tribute to Rodrigues and its people for their care for nature.”

Factsheets presenting the latest assessments for all 11,185 bird species are available on the BirdLife DataZone. More information about the IUCN Red List categories and criteria is available here.