HMN 2025: How to Chronicle each identified terrestrial extinction within the Macaronesian islands

Because their relative isolation encourages speciation, oceanic islands are hotspots of biodiversity. Yet their comparatively small dimension, atypically defenseless animals and crops, and ecological vulnerability to the consequences of launched species has additionally made them hotspots of extinction.

Jairo Patiño, José María Fernández-Palacios and colleagues chronicle each identified terrestrial extinction in Macaronesia—an space within the Atlantic Ocean comprising the volcanic archipelagos of the Azores, Madeira, Selvagens, the Canaries, and Cabo Verde. The work is published in PNAS Nexus.

The survey uncovered 220 extinctions representing 3.1% of the Macaronesian endemic species, of which 111 have been land snails, 55 have been arthropods, 27 have been birds, and 15 have been reptiles—together with a number of species of large tortoises. Half of the endemic birds of those islands are actually extinct. Plants fared better, and lichen and fungi noticed no recorded extinctions—though that result’s seemingly influenced by an absence of information for these taxa.

Of the 220 extinctions, half are clearly related to human arrival—significantly the arrival of the Portuguese and Castilian colonists and their home animals within the fifteenth century. Some extinctions have been seemingly associated to climatic adjustments or volcanic occasions earlier than human arrival, however the price of extinctions within the post-human interval is greater than 12 occasions larger than the speed earlier than people arrived.

Extinct birds embody the São Jorge rail (Rallus nanus) from São Jorge Island within the Azores; the Madeiran Scops Owl (Otus mauli) from Madeira Island; the slender billed greenfinch (Chloris aurelioi) from Tenerife within the Canary Islands; and the São Vicente Quail (Coturnix centensis) from São Vicente Island in Cape Verde. According to the authors, conservation and habitat restoration are crucial to gradual the speed of extinction in Macaronesia.