Flying over the sea: discover the world of seabirds
When talking about seabirds, only one bird usually comes to mind: the seagull. Overall, we can say that most people are unaware of the diversity of birds that inhabit our seas. Which is not very surprising, considering that most species of seabirds fly far away from our eyes. Our whale and dolphin watching trips give us an excellent opportunity to enjoy these birds (flying over the sea).
Flying over the sea: For someone who is taking his first steps in the world of ornithology (observation and study of birds) he has a complicated task at hand, as it requires a well-trained vision. The elegant flight of a bird looking for food can be confused with a simple “shadow” movement on the horizon. But once our curiosity is piqued, our senses stimulated and our vision refined, we can enjoy the great diversity of birds that roam our ocean.
What are seabirds?
There is a wide variety of species of seabirds that we can observe right here in the Azores. From the best known as the yellow-legged gull to the wide variety of shearwaters (Shearwaters, Alma negra, Frulho, Estapagado, Cory’s Shearwaters), passing through the always elegant Tern (common and pink tern) and ending with the small 25 grams (Painhos da Madeira, forced-tail or Monteiro).
Photograph 1 – flying over the sea- Adult Common Tern (Sterna hirundo)
Photograph 2 – Flying over the sea – Juvenile Common Tern (Sterna hirundo)
Some birds can have a long lifespan (up to 60 years old) and reproduce at a very slow rate (many species only lay one egg per year). Precisely because of this, these animals are very sensitive to changes in their environment, which has led to a drastic reduction in some populations. They usually breed in colonies that can have several hundred and even thousands of pairs, located in inaccessible areas such as cliffs. They spend most of their life flying over the sea, where they find their food: fish, crustaceans, molluscs and other marine animals. They are found at the highest levels of the marine food chain, being excellent indicators of the state of conservation of ecosystems.
Precisely because they live a large part of their lives in the open sea, we raise some questions about these magnificent creatures:
- How do they manage to spend most of their lives in the salt water of the sea?
- How do they manage to stay in the water for so long?
- Can they take off with wet plumage?
Seabirds (flying over the sea) can present a wide variety of anatomical and physiological adaptations, which make the sea, such a hostile environment for the rest of the birds, their ideal habitat. Many of them waterproof their feathers with a wax produced through a gland called “uropygial”, which is located at the base of their tail. When we watch them straighten their plumage, they are actually distributing the wax through their feathers. Its paws have an interdigital membrane between their toes, providing a greater surface for contact with water, making it easier to swim. In addition, they also have glands that efficiently eliminate excess salt from their body.
Importance of the Azores for seabirds
The Azores Archipelago, due to its geographical position and isolation, thousands of kilometers from any continent, constitutes an important crossing area for many species of seabirds. The archipelago is actually an isolated retreat in the middle of the Atlantic along its migration routes.
The birds approach the coastal zone of the Azores and look for islets or isolated cliffs that serve as nesting areas (areas where birds lay their eggs) and resting. It is so important that some species are highly dependent on our islands.
It is important to mention, for example, the case of Cory's ShearwaterCalonectris diomedea borealis), the most abundant seabird in the Azores, where the Azorean nesting population represents 74% of the world population of the subspecies Calonectris diomedea borealis and 52% of the species Calonectris diomedea.
Photo 3 – Cory's Shearwater flying over the sea (Calonetris diomedea borealis).
Likewise, the position of the Archipelago between America and Europe makes the western islands an important refuge for birds of American origin that are brought by storms, very rarely seen in Europe. These occasional events delight all ornithologists and birdwatchers (aka birdwatching).
Seabirds and the Azorean people
For the Azorean people, with a tradition and history so linked to the sea, seabirds have always had a strong connection with people who look to the sea for their way of life.
Some of the most abundant birds on the islands, such as shearwaters, were once hunted by the islanders. The Cory's Shearwater was very popular for its meat and also for its feathers and fat, as described by Gaspar Frutuoso. Today the Cory's Shearwater is listed as “vulnerable” in the Red Book of Vertebrates of Portugal and is protected in the Azores.
The relationship between seabirds and fishermen is especially strong. Fishing affects seabirds and their environment in different ways, representing a serious threat, but it is also a potential ally. If, on the one hand, seabirds can be indicators of the location of fish banks, on the other hand, marine pollution from fishing gear and human activity in general, contribute to habitat deterioration and population reduction.
Also in our Whale-Watching activity, the help of seabirds is essential to find cetaceans in the vast ocean. Sometimes the lookouts can see the dolphins due to the presence of large “birds”, where the birds, in coordination with the elegant dolphins, find and corner their prey.
Threats to seabirds
Unfortunately, like many other groups of animals, these wonderful birds are heavily endangered, largely because of humans. Their dependence on both the marine and terrestrial environments doubles the number of threats they face. At sea, the presence of plastic, toxic substances and other types of pollution is a serious problem. On the other hand, overfishing makes it more and more difficult to find food, and can even contribute to their death, when they become caught in hooks or fishing nets.
On land, the presence of predators such as cats or mice in their nesting areas causes damage to many of their colonies. At the same time, excessive urban development and coastal degradation reduce the number of areas available for nesting. A particularly serious impact is the intense lighting of the coast, which can disorient the young birds when leaving their nests, and they can end up dying.
We can say that seabirds are the most threatened group of birds in the world: more than a third of the 346 known species are threatened globally, several of them on the verge of extinction.
The conservation of seabirds in the Azores
Fortunately, the Azoreans are increasingly aware of the conservation of their natural resources. We can find an increasing number of citizens and institutions involved in the conservation of this group of animals.
An example of what we have just mentioned is the SOS Cagarro campaign, which is promoted every year by the Government of the Azores. This campaign, disseminated to the population through information leaflets, social networks and the media, involves the population and institutions in rescuing juvenile shearwaters found “lost” on roads near coastal areas. The campaign aims to demonstrate the care to be taken when young birds are found: in case of being run over, on days of intense fog or at night when they are chained.
Other projects such as LIFE Ilhas Santuário para aves Marinhas in Corvo and Ilhéu de Vila Franca do Campo, which began in 2009, whose objective is the conservation of seabird colonies in the Azores through the recovery of their habitat and measures to control and eradication of introduced invasive species. This is a project coordinated by the Portuguese Society for the Study of Birds (SPEA) in partnership with the Regional Secretariat for the Environment and the Sea (SRAM), the Municipality of Corvo and the Royal Society for the Protection of Birds (RSPB).
