Biogallery

Get to know the Species

Black stork

In spring, migratory birds bolster the Portuguese black stork population and in the autumn, they leave the country for Africa. Some of them fly along the coast in an elegant manner, alternating between vigorous wingbeats and calmer moments when they glide, seemingly suspended in the sky.

Whether on land or in the air, the black stork (Ciconia nigra) is a species that is easy to identify due to its dark contrasting colours, size and beauty. The dark, glossy plumage on its upper body and neck and the white areas on its underside, along with its long, reddish legs and beak are distinctive features. In sunlight, its black feathers reflect a greenish-purple hue.

Despite its large size—its wingspan can extend to more than two metres—the black stork is very light and weighs no more than three kilos, which helps it to glide.

Much less common in Portugal than its “cousin” the white stork (Ciconia ciconia), the rare black stork is a bird that can be found both residing here and as a migratory species. According to the organization Aves de Portugal (Birds of Portugal), this sort of overlap is not very common.

During spring and early summer, the black stork lives and nests across Europe and much of Asia. As autumn approaches, most of the population flies south to spend the winter in warmer climes. Some of them, however, remain all year round in Portugal and also in Spain. Globally, this overlap between residents and migrants is only observed on the Iberian Peninsula and in southern Africa.

Thus, at the end of September and beginning of October, many black storks that have nested in Portugal and other European countries fly towards Sub-Saharan Africa. Although Gibraltar is the preferred spot for crossing the Mediterranean Sea, some deviate from this route and can be seen in Portugal either stopping or flying across the sky. During this season, they can be seen mainly along the coast: Sagres is one of the best places to see this and other migratory birds according to SPEA – The Portuguese Society for the Study of Birds.

The native ones live mainly in the inland part of the country and the migratory ones nest mainly in the areas surrounding three large rivers, the Douro, the Tagus, and the Guadiana, typically in the parts straddling the border with Spain. Its preference for quiet areas with an abundance of water—rivers, streams, ponds, and dams—is also justified by its diet which, although it contains insects and small mammals, such as small rats and other birds, is rich in fish, crustaceans, and amphibians.

The black stork is a shy bird and it nests in steep areas and in large trees with vast canopies, from cork oaks (Quercus suber) and stone pine (Pinus pinea) to holm oaks (Quercus rotundifolia) and some eucalyptus, pine, and other oak trees. Females lay three to five white eggs, which they incubate for 30 to 40 days. The chicks remain in the nest until they can fly and are fed for just over two months. After this time, the parents leave the nest and the chicks behind.

Did you know that…

  • In Portugal, there are around 100 pairs of black stork, according to the ICNF – Portuguese Institute for Nature Conservation and Forests, which has been monitoring the species since 1995. In its 2021 census, it identified ten pairs and 21 unfledged chicks, which indicated an increase in the number of chicks in the Douro International region.
  • Black stork nests are made up of sticks and mud and are often used repeatedly year after year. Disruption to their habitat can lead to the temporary abandonment of the nest, their eggs, and young. This is especially critical in the incubation phase and after hatching, as it can lead to loss of the eggs and small hatchlings. Water contamination, collisions with power lines, the construction of water, road, and even recreational or tourist infrastructure are some of the threats facing the species.
  • One of the main differences between the black and white stork is in the colour distribution of their plumage: the upper part and neck are entirely dark in the former, while in the latter, only the flight feathers (on the end segment of the wings) are dark. The white stork is a bit bigger, a lot more common in Portugal, and less shy. Unlike the black stork, which is difficult to spot, white storks live near urban areas and nest there in elevated areas, from trees to man-made structures such as electricity pylons, church towers, chimneys, and even in occupied premises, such as factories.
  • BIRD

  • Black stork

    Ciconia nigra

  • Genus:

    Ciconia

  • Family:

    Ciconiidae

  • Threat status:

    “Vulnerable Species” (VU) in Portugal and “Least Concern” (LC) worldwide (according to the International Union for Conservation of Nature’s Red List. It is protected by Annexes I and II of the Berne and Bonn Convention and also by Annex II of the CITES Convention.

  • Habitats:

    Slopes next to waterlines and mountains, mature forests and agroforestry areas, which do not tend to be disturbed.

  • Distribution:

    All over Europe, a significant part of Asia and Africa. In Portugal, it can be observed mainly in the inland part of the country and also migrating along the coast, especially near Cape St. Vincent in the Algarve.

  • Height/Length:

    Between 90 and 105 centimetres in length, with a wingspan of between 170 and 205 centimetres.

  • Longevity:

    Between 20 and 30 years in the wild.

How do we look after black stork populations?

Black storks have been sighted in some of the forest areas managed by The Navigator Company, from Mogadouro in the Northeast of Portugal to Nisa, where it nests, and in the Sado Valley and Alentejo.
In Nisa, during wildlife monitoring, a nesting site was discovered on a rock in 2016. Barring one year, the same site has been successfully used for annual nesting between 2016 and 2022.

Since the black stork feeds within a radius of about 20 kilometres around the area it nests, the main measures applied in the forest areas managed by the company are aimed at preserving the watercourses and ponds, which are important feeding grounds. The preservation of these freshwater areas is important for both resident and migratory populations that nest in Portugal and even for those that cross the country on their journeys and stop off to feed.

In addition, where justified, temporary measures are also taken to prevent activities on the ground that could disturb nesting sites.

Temas: