Advancing the conservation of the critically endangered Raso Skylark on the Cape Verde Islands

The Bird Conservation Fund (BCF) is teaming up with the African Bird Club (ABC) to raise $6,670 to deepen the understanding of the predation risks that are threatening Raso Skylark, one of the globe’s rarest and most threatened species.

The Raso Skylark (Alauda razae) is one of the rarest and most threatened birds in the world. It’s total population has fluctuated from a low of 130 individuals (2001) to a high of 1490 (2011). This species was confined to the small oceanic island of Raso (Cape Verde) until its translocation in 2018, to the nearby Santa Luzia Island. The population fluctuates in response to rainfall and its survival is highly dependable on successful incubation time and minimal predation risk. In 2021, the project team carried out a first preliminary study of this species in Santa Luzia Island, following its translocation. Unfortunately, they documented a heavy predatory impact on eggs from mice and birds.

The proposed assessment of predation of adults and nests on Santa Luzia Island is essential for its survival. Nest success rates remain poorly studied but it is considered to be naturally very low on Raso, which is free of any introduced mammals, but heavy predated by the giant gecko Tarentola gigas, itself a threatened species. The adaptation of this bird to different ecosystems and predation pressures will be crucial for its long-term survival and conservation management. Therefore, the project team aims to estimate the impact of its potential predators. For this, the team will study the synergy of the three desert islands (Raso, Saint Luzia and Branco) together with the particular and unique aim to compare their different ecological situations in respect to the Raso Skylark population. The study on Branco might determine a future low predator translocation environment for the Raso Skylark.

After translocation to Saint Luzia heavy predatory impact on eggs found, assigned to mice and bird predators. Therefore, aim to estimate impact of potential predators. Study the synergy of the three desert islands (Raso, Saint Luzia and Branco) to compare their different ecological situations in respect to the skylark population. The study on Branco might determine a future low predator translocation environment for the Raso Skylark. Aims will be to (i) identify the different potential predators present in these different ecosystems (ii) estimate more precisely the presence of introduced mammals with bait trapping; (iii) assess relative impact of predators on experimental nest survival compared to original Raso Island ecosystem.

The project will be initiated in October 2024, and the Bird Conservation Fund is working with the African Bird Club to raise the funding to support the project team Dr. Stephane Caut, Michael Jowers, and Evandro Lopes.