The appearance of vultures is traditionally an ill-omen, but not this time. Two breeding pairs of Eurasian black vultures have shown up in southern Portugal, marking the return of this critically endangered species after a whopping four decades away.

As you likely knew, vultures feast on the carcasses of other animals, earning themselves infamy for ominously circling above like harbingers of death. They also aren't friendly looking animals, with oily black feathers, a balding head, and a cruelly curved beak designed for the ripping and tearing for flesh.

Between shrinking habitats, a decline in local prey, and increasingly frequent power line collisions, vultures became very rare in Portugal by the mid 1950s. According to conservation group Fauna and Flora International (FFI), the poisoning of carcasses as a means for controlling wild dog populations eventually led to the unintentional decimation of the region's remaining population, with the last black vulture breeding pair disappearing by the 1970s. Globally, the species was classified as near-threatened.

Effort to see these birds - an essential clean-up crew in the Portugal's ecosystem - return saw some breeding pairs finally reappearing in Portugal by 2010. However, with the birds remaining absent in well over half the country, it was locally designated as a critically endangered species.

That's why the reappearance of these pairs in the south is a source of new hope. FFI partner Liga para a Protecção da Natureza (LPN) had first reported spotting these breeding pairs closely following the completion of several artificial nesting platforms created by the LIFE-Nature project "Habitat Lince Abutre." (Scroll to read on...)

"After more than forty years without confirmed breeding south of the Tagus River in Portugal, a period during which only a failed nesting attempt was registered (about twenty years ago and on the same area), the settling of these two Black Vulture pairs on these artificial nests represents a success of the conservation [project] and an important milestone for Black Vulture conservation in Portugal," the LPN announced.

The hope is that these pairs are but the first of a growing breeding colony, as has already been seen to a small extent in northern Portugal.

The Eurasian black vulture (Aegypius monachus) is one of the world's largest birds of prey, with a wingspan that can reach almost three metes across. It is found mainly in forested habitat, and feeds on the carcasses of wild rabbits and domestic livestock.

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