Alexander’s Swift: Cape Verde’s Endemic Aerial Acrobat
In the vast, azure expanse of the central Atlantic Ocean, the archipelago of Cape Verde (Cabo Verde) rises from the waves as a volcanic marvel. Located between 600 and 850 kilometers west of the African coast, these ten islands are home to a unique evolutionary laboratory. Among the most remarkable results of this isolation is Alexander’s Swift (Apus alexandri), a bird that embodies the spirit of the islands: resilient, energetic, and found nowhere else on Earth.
The Master of the Macaronesian Winds
Alexander’s Swift is a small, dark, cigar-shaped bird that belongs to the Apodidae family—a name derived from the Greek word for “footless.” While the birds certainly have feet, they are so small and specialized for clinging to vertical cliffs that they are rarely seen on the ground. For Alexander’s Swift, life is lived almost entirely in the air.
Endemic to the Cape Verde islands, this species is a distinct part of the Macaronesia ecoregion’s biodiversity. While it shares some physical similarities with the Common Swift found in Europe, Alexander’s Swift is smaller, with a paler throat and a distinctively rapid, flickering wingbeat that allows it to navigate the turbulent thermal currents created by the archipelago’s dramatic volcanic topography.
Habitat and Distribution Across the Archipelago
The geography of Cape Verde is divided into two main clusters: the Barlavento (windward) islands and the Sotavento (leeward) islands. Alexander’s Swift can be found across most of these islands, though its presence is most felt where the terrain is most rugged.
In islands like Santiago, Santo Antão, and Fogo, where the landscape is defined by towering mountains and deep “ribeiras” (valleys), these swifts find their ideal habitat. They are frequently seen swirling around the majestic Pico do Fogo, an active volcano reaching 2,829 meters above sea level, or darting through the humid mists of the mountain forests where condensation allows for lush vegetation in an otherwise arid climate.
Conversely, on the flatter, desert-like islands of Sal and Maio, they may be less common but are still spotted near sea cliffs and salt flats, hunting the insects that thrive in the coastal breeze.
Key Identification Features:
- Size: Smaller than the European Common Swift (approximately 13 cm in length).
- Coloration: Generally dark brown with a subtle, pale grey-white throat patch.
- Flight Style: Characterized by incredibly fast, shallow wingbeats interspersed with short glides.
- Voice: A high-pitched, screaming “shree” often heard when birds are in groups.
Life on the Wing: Ecology and Behavior
The ecology of Alexander’s Swift is a testament to adaptation. In a country where only two percent of the land is arable and rainfall is irregular, these birds have mastered the art of “aerial plankton” harvesting. They feed on a wide variety of airborne insects, often concentrating in areas where orographic lift pushes air—and bugs—up the sides of steep cliffs.
During the breeding season, which typically aligns with the arrival of the irregular rains between August and October, the swifts become particularly active. They nest in the crevices of volcanic rock, in the roofs of old colonial buildings in cities like Mindelo or Praia, and even in the sea caves carved by the Atlantic’s powerful swell. Their nests are constructed from feathers, grass, and down, glued together with their own sticky saliva—a common trait among swifts.
Conservation in a Changing Climate
Despite being a symbol of the islands’ natural heritage, Alexander’s Swift faces challenges. Cape Verde is on the frontlines of the global climate crisis. Ranked as one of the most endangered nations due to rising sea levels and flooding, the archipelago’s delicate ecosystems are under pressure. Changes in rainfall patterns affect insect populations, which in turn impacts the swifts’ food supply.
However, there is hope. The Republic of Cabo Verde has become a leader in renewable energy and environmental conservation in Africa. With a goal to reach 50% renewable energy by 2030 and recent “debt-for-nature” swaps with Portugal, the nation is investing heavily in protecting its endemic species. The preservation of the Macaronesian dry forests and the regulation of human development on steep slopes are critical steps in ensuring the skies of Cape Verde remain filled with these aerial acrobats.
The Best Places to Observe Alexander’s Swift
For birdwatchers and nature enthusiasts visiting Cape Verde, observing Alexander’s Swift is a highlight. Unlike the more elusive Raso Lark, these swifts are ubiquitous if you know where to look.
1. Santo Antão
The craggy peaks and deep ravines of Santo Antão offer some of the most spectacular sightings. As you hike the trails between Cova and Ribeira Grande, you can watch the swifts performing high-speed maneuvers against the backdrop of verdant terrace farms.
2. Fogo
The caldera of Pico do Fogo is a surreal place to witness these birds. They are often seen soaring along the rim of the 8-kilometer-wide caldera, silhouetted against the dark volcanic ash.
3. Cidade Velha, Santiago
In the historic Cidade Velha, a UNESCO World Heritage site and the first permanent European settlement in the tropics, you can see the swifts nesting in the ancient stone walls of ruins and churches, bridging the gap between Cape Verde’s human history and its natural wonders.
Conclusion
Alexander’s Swift is more than just a bird; it is a link to the ancient, volcanic origins of the Cape Verde islands. In its rapid, tireless flight, one sees the endurance of a nation that has transitioned from a strategic Atlantic outpost to a stable, thriving democracy. As Cape Verde continues to champion environmental sustainability, this endemic swift remains a soaring reminder of the unique beauty found in the heart of the Atlantic.
Image: Pexels – Magic K
