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Launched in 2017 , our bird monitoring programme is the first comprehensive field study on Sal’s resident and migratory bird species.


Birds, and especially seabirds, serve as important indicators of the health of the surrounding ecosystem. Our team collects critical nesting, feeding, and migration data on several key indicator species.


Rapid coastal development, overfishing, marine pollution and the introduction of domesticated species such as cats and dogs are placing increasing pressure on the habitats and feeding patterns.


Our bird monitoring team currently works with over seven species of birds on Sal island to better understand their roles in the island’s ecosystem. Our collection and analysis of this data will provide an essential roadmap for developing future conservation strategies of these important birds.

Seabirds: A Barometer for Biodiversity

Seabird populations, their breeding habits and their diets all offer important insight into the health of the surrounding marine ecosystem. As marine predators that are accessed with relative ease, the remains of their diet provides us with a fresh sample of their prey species, that can be simultaneously studied in real time.

Seabirds play important roles as:

Biological Indicators


Their health reflects the quality of their surrounding environment and any changes it undergoes over time.

A Source of Nitrogen

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The nitrogen and potassium from their excrement (also known as guano) provide essential nutrients for soil and ocean cycles as well as for local plant vegetation.

Natural Ocean Samplers


By taking samples of their diet researchers are looking for the presence of organic and inorganic contaminants. 

Seabirds at a Glance:

340 Species Globally

We can find up to 350 species of seabirds in the World. From them, 8 can be found in Cabo Verde and 5 in Sal Island.


Specilized Fishers

They have waterproof feathers that allow them to plunge-dive to catch fish and squid. Others, like penguins, use their wings like fins.

Drink Saltwater

They evolved with a sal processing gland that allows them to drink salt water. The excess of salt is excreted through the nostrils.

Colonies & Migrations

Seabirds breed in aggregations or colonies that they leave to migrate to feeding areas with species rich in their diet.


Red-billed tropicbird

Red-billed Tropicbird


  • Habitat: Coastal cliffs, in rocky areas and cliffs. Nest inside holes.

  • Breeding season: year-round breeding with a seasonal peak from December-April.

  • Migration: middle of Atlantic Ocean, between CV and the north of South America.

  • Threats: predation by humans, introduced animals (rats, cats, dogs), accidental catches by fisheries. Least Concern (UICN).

  • Population trend: Decreasing

Red-billed Tropicbirds

Red-billed tropicbirds (Phaethon aethereus) are a loosely colonial species that nest in the rocky cliffs where there is easy access to the open sea. Their diet consists primarily of small fish and squid caught by plunge-diving. 
It’s in part their breeding patterns that make Red-billed tropicbirds particularly sensitive to environmental changes.
This species often return to the same locations to breed and remain as a pair throughout their lifetime making them increasingly vulnerable to threats such as predation from introduced species such as cats, rats, and other mammals, as well as human-induced threats such as ocean pollution and poaching of adults and chicks.
Red-billed tropicbirds are nationally protected throughout Cabo Verde, though this particular population is still listed as endangered.​

In 2018, our team's data collection in the field led scientists from the University of Barcelona to identify Sal island as likely the most important breeding site for Red-billed tropicbird in West Africa.

Volunteer with us!

If you are looking to kick-start your career in ornithology and develop new skills, our new bird volunteering programme is for you! Gain hands-on field experience working with locally and globally iconic species. We're only taking a limited number of volunteers this season and are looking for people ready to make a meaningful contribution and who are prepared for some challenging, but very fulfilling work.

Seabird Species in Sal

Seabirds of Sal Island

In addition to the Red-bill Tropicbird, our team has recorded four other species of seabird currently nesting on Sal island. Though these species share a number of the same general characteristics of seabirds, they each possess their own unique breeding and migratory patterns. 

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Cape Verde little Shearwater

Puffinus boydi

  • Endemic of Cabo Verde

  • Local Name: Pedreiro

  • Status (IUCN): Least Concern

  • Habitat: on the coast, in rocky areas and cliffs. Nest inside holes.

  • Breeding season: February- May

  • Migration: between CV and the north of Brazil.

  • Threats: introduced animals (rats, cats), mortality associated with light pollution.

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Cape Verde Shearwater

Calonectris edwardsii

  • Endemic of Cabo Verde

  • Local Name: Cagarra

  • Status (IUCN): Near Threatened

  • Habitat: on the coast, in rocky areas and cliffs. Nest inside holes.

  • Breeding season: June- November

  • Migration: south of Brazil and Uruguay

  • Threats: predation by humans, introduced animals (rats, cats), accidental catches by fisheries.

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Cape Verde Storm-petrel

Hydrobates jabe jabe

  • Endemic of Cabo Verde

  • Local Name: Pedreirinho

  • Status (IUCN): Vulnerable

  • Habitat: on the coast, in rocky areas and cliffs. Nest inside holes.

  • Breeding season: possibly in two different seasons, not enough info

  • Migration: Unknown

  • Threats: introduced animals (rats, cats), mortality associated with light pollution

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Bulwer's Petrel

Bulweria bulwerii

  • Local Name: João Preto

  • Status (IUCN): Least Concern  

  • Habitat: on the coast, in rocky areas and cliffs. Nest inside holes.

  • Breeding season: June- September

  • Migration: middle of the Atlantic Ocean, between west África and the north of Brazil.

  • Threats: introduced animals accidental catches by fisheries and mortality associated with light pollution.

Threats to Seabirds

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Marine Pollution

Over 90%  of seabirds have ingested some form of plastic. Plastic found inside birds includes bags, bottle caps, synthetic fibers from clothing. Even worse, plastic is often transferred from the fish in their diet to both the adults and the chicks, creating a cycle of plastic consumption that is difficult to break. 

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Predation by Introduced Species

Predation by introduced species such as dogs and cats pose a significant threat to seabirds. In Sal, lack of capacity to control stray animal populations has placed species like the Red-billed tropicbird and others at increased risk. 

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Light Pollution

The presence of light pollution from buildings near seabird habitats disorients the seabirds, which are normally nocturnal. As a result, many seabirds land by the light and if they are not rescued they could face predation.   

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Destruction of habitat due to coastal construction

Unregulated construction as a result of the rapidly-expanding tourism industry continues to threaten coastal seabird habitats. 

Tools for Conservation

Tools For Conservation

​​Until recently, little was known about the health and conservation status of the seabird species on Sal. As an indicator species, seabirds can assist in piecing together important information about the health of the surrounding ecosystem and environment. In partnership with the University of Barcelona's Seabird Ecology group, we are working on collecting specific data that will provide critical information on the health of Sal's seabird populations, and by extension, the surrounding ecosystem. 

Here are a few ways we are measuring the health of seabird species on Sal: 

Sampling of adults

  • Uropygial fat to help identify organic and inorganic contaminants;

  • Blood extraction to determine the sex of the animal;

  • Feathers: to collect information on the diet of the local population.

Movement tracking​

  • Placement of geolocators to determine migration patterns and areas of travel after their breeding season;​
  • Placement of GPS devices to determine feeding areas during the incubation and the rearing periods and the differences between incubation and breeding periods;

  • Placement of GPS devices on boats: determinate human-seabirds conflict.

Ringing and biometrics

  • Support population study - tracking the size of the population here on Sal, as well as learn more about the age and duration of sexual maturity;

  • Control the weight and measurements of both adults and chicks to know the food supply status - less weight gain could mean a depletion of fish stocks.

Other bird monitoring initiatives

Other Monitoring Initiatives

Coming soon
Wader Birds
Wader Birds
Coming soon

Main project partners:

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