Celebrating Our Skyward Nomads: Common Swift

Birdlife International shines a spotlight on a different migratory bird species, showcasing its unique characteristics, incredible journeys, and the efforts being made to protect its habitat. After celebrating the splendor of past migratory stars such as the European Turtle-dove (Streptopelia turtur) or Black-backed Shrike (Lannius collurio), now its turn focus to an avian marvel that truly embodies the boundless freedom of the skies—the Common Swift (Apus apus).

These birds have captivated hearts with their unparalleled flight capabilities and fascinating lifestyle, making them a perfect candidate for this month’s feature. Known as the true monarchs of the skies, Common Swifts spend nearly every moment in the air, only landing when it’s time to breed. Their graceful aerial maneuvers and incredible endurance not only inspire awe but also highlight the remarkable resilience of migratory species. This month, the article explores their life, migratory patterns, and the growing conservation efforts to secure their future in our ever-changing world.

I am deeply grateful for the Common Swift, the true master of the sky. Their graceful flight, endurance, and long migrations are a beautiful reminder of nature’s wonders. They fill our summer skies with life, connecting continents and seasons in a way that few creatures can.

Key Facts

• Scientific Name: Apus apus
• Conservation Status: Least Concern BirdLife International
• Global Population: Estimated between 95,000,000 and 164,999,999 mature individuals.
• European Population: Around 19,100,000 to 32,500,000 pairs, translating to 38,200,000 to 65,000,000 mature individuals. European Bird Census Council
• Migration Route: African-Eurasian Flyway

Physical Characteristics

• Wingspan: 36-40 cm
• Lifespan: Up to 20 years
• Distinctive Features: Sleek dark plumage, scythe-like wings, forked tail
• Diet: Insects caught mid-flight
• Top Speed: Up to 111 km/h
• Habitat: Urban areas, cliffs, woodlands, and even on your building

Common Swift: Apus apus

Mastering the Skies

The Common Swift is a species like no other, known for its unmatched ability to stay airborne for most of its life. These sleek, scythe-winged birds are built for flight, with bodies perfectly adapted to life in the sky. Once they leave the nest as juveniles, they spend the next two to three years in constant flight, not touching the ground until they are ready to breed. During this time, they eat, drink, sleep, and even mate on the wing.

Such an airborne lifestyle has shaped not only their behavior but also their anatomy. Their streamlined bodies, long wings, and small, underdeveloped feet make them true aerial acrobats. Their incredible adaptation to the skies showcases the marvels of avian evolution and makes them an essential species for study and admiration.

The Epic Migratory Journey

Common Swifts embark on one of nature’s most remarkable migratory journeys, traveling thousands of kilometers between their breeding grounds in Europe and Asia and their wintering areas in sub-Saharan Africa. They follow the African-Eurasian Flyway, a migration route that poses numerous challenges, from adverse weather conditions to dwindling insect populations. On average, a Common Swift can cover between 570 to 800 kilometers in a single day, often flying at altitudes of up to 2,500 meters.

For a detailed view of the distribution of the Common Swift (Apus apus), please refer to the distribution map provided by BirdLife International. Access the map here.

Their incredible endurance and speed enable them to navigate these vast distances with grace and precision, earning them the title of some of the fastest birds on long-distance migrations. This epic journey not only illustrates their resilience but also underscores the importance of conserving migratory routes, which are critical for the survival of many bird species.

The Threats They Face

Although Common Swifts are currently listed as “Least Concern” by the IUCN, they are not immune to the pressures of habitat loss, food scarcity, and climate change. As urban areas expand, traditional nesting sites in buildings and natural structures like cliffs are disappearing. Modern construction practices often seal off potential nesting cavities, leaving fewer safe spaces for these birds to breed.

Additionally, the widespread use of pesticides has led to a decline in insect populations, the primary food source for swifts. Climate change further exacerbates these threats by altering weather patterns and the availability of prey, disrupting their carefully timed migratory and breeding cycles. These combined challenges highlight the need for conservation efforts that address both habitat preservation and sustainable practices to protect this incredible species.

Conservation Efforts

To combat these challenges, BirdLife International and its partners are working tirelessly to conserve swift populations and their habitats. The “Save Our Swifts” initiative is a concerted effort to protect nesting sites, particularly in urban areas where building renovations and modern architecture pose a threat. This project aims to promote swift-friendly building practices, ensuring that new constructions and renovations include features that provide safe nesting opportunities.

BirdLife partners have developed technical guides for architects and developers, available in multiple languages, to encourage the incorporation of nesting sites in building designs. For example, Spanish SEO/BirdLife and French LPO partners have created comprehensive documents outlining simple yet effective measures for swift conservation.

Conservation isn’t just for organizations—individuals can play a vital role as well. By setting up swift nesting boxes on homes and buildings, anyone can create a welcoming environment for these remarkable birds. BirdLife’s partners, including Germany’s NABU and the UK’s RSPB, provide easy-to-follow guides on how to install nesting boxes, enabling everyday citizens to become active participants in the protection of Common Swifts.

• Setting up a Swift Nesting Box in German: NABU
• Setting up a Swift Nesting Box in English: RSPB

How Can You Help Common Swifts?

The Terracotta Swift Nesting Brick Box is a simple yet effective nesting solution for swifts, designed for new builds and modern brick houses. It replaces a standard 9″ x 3″ brick and can be easily installed during construction. With its colored face, it blends seamlessly into the surrounding masonry. The box features a 29 x 65mm entry tunnel, leading to a spacious 413 cm² nesting area, while a built-in cavity tray protects against water ingress. Developed in partnership with house builders and conservation experts, this nesting box helps support the declining swift population by providing safe nesting sites. Other colors are also available.

The Esschert Design NKC Nest Box for Common Swifts is a sturdy, brown wooden box made from pine with a zinc roof, weighing 2.24 kg. Designed specifically for swifts, it features an easy-to-open side for convenient cleaning and requires no assembly. For best results, hang this nest box in a quiet, sheltered place to provide a safe environment for nesting swifts.

Fascinating Facts

A Life on the Wing

Few birds can claim to live as much of their lives on the wing as the Common Swift. These birds do almost everything while airborne—feeding on insects they catch mid-flight, drinking water as they skim across lakes, and even sleeping by alternating between the hemispheres of their brain to remain active to keep them safe during rest. It’s a remarkable lifestyle that has fascinated scientists and bird enthusiasts alike.

Their name, apus, comes from the Greek word meaning “without feet,” a nod to the bird’s airborne existence and small, inconspicuous feet adapted for clinging to vertical surfaces during nesting. Despite rarely being seen up close, their distinctive silhouette and characteristic screaming calls make them a familiar sight in summer skies, where they dart and swoop in pursuit of prey. However, this aerial mastery comes at a cost; modern threats like urban development and pesticide use are encroaching upon the Common Swift’s habitat, making their conservation more crucial than ever.Skyward Sovereigns

Companions in Flight

One of the most intriguing aspects of Common Swift’s life is its relationship with a peculiar companion: the Common Swift louse fly (Crataerina pallida). This small, wingless parasite clings to its host throughout the journey, living among the swift’s feathers. Although the idea of parasites might sound unpleasant, the relationship between swifts and their lice flies is a natural one.

These freeloaders do not pose significant harm to the swifts and have evolved to live exclusively with these airborne birds. Almost all swifts host these companions, which can become quite visible as they move through the feathers. While little is known about any potential benefits this relationship might have for the birds, it is a fascinating example of the complex interactions within nature that accompany migratory life.

Celebrating Swift Conservation

The popularity of Common Swifts has surged as awareness of their plight grows. Notable advocates include environmentalist Hannah Bourne-Taylor, who has passionately campaigned for their protection, and Jane Goodall, a well-known conservation icon and animal welfare activist who supports these amazing birds.

For more insights, check out this video featuring Jane Goodwall on World Swift Day: Watch Video.

Embrace the marvel of the Common Swift, and join the efforts to preserve these incredible aviators for future generations.

References:

1. IUCN Red List: Common Swift ↩︎
2. BirdLife International (2024). Species factsheet: Common Swift Apus apus. Downloaded from https://datazone.birdlife.org/species/factsheet/common-swift-apus-apus on 30/07/2024. ↩︎
3. S. Åkesson, G. Bianco (2021). Wind-assisted sprint migration in northern swifts, DOI: https://doi.org/10.1016/j.isci.2021.102474 ↩︎
4. Ander Hedenström et al. (2016). Annual 10-Month Aerial Life Phase in the Common Swift Apus apus ↩︎