Yeah.
Between the sky and the time.
Between the sky and the tides.
This is one of the few Portuguese rivers that flows north, the Sado.
Close to the Atlantic Ocean, its waters facing the surrounding terrain form a large estuary.
Separated from the ocean by the long sandbar of the Troia Peninsula, the broad estuary offers a haven for wildlife, especially for waterfowl.
The Sado estuary is a natural reserve and is classified as a wetland of international importance according to the Ramsar Convention.
Here the main driving force of life is the tides.
They support and provide for everything that lives in the estuary.
As the tide goes out, new habitats are revealed.
The freshly exposed mudflats are teeming with life.
Dozens of species wait for the water to recede to feed on small mollusks and crustaceans.
The sediment layers of the channels shelter many invertebrate communities, living a few centimeters beneath the surface, such as crustaceans, mollusks, worms, welks, and many more.
These organisms not only recycle nutrients and extract toxic substances from the water, they also represent the main food source for the animals of the estuary.
However, birds are not the only ones seeking these buried treasures.
Among all bird species that forage here, one stands out.
The Eurasian Spoonbill is one of the most unmistakable estuary birds.
The bizarre bill shaped like a spoon is used for feeding.
It sweeps its bill from side to side in the silt disturbed by its feet, and when it comes into contact with an aquatic creature, the bill snaps shut.
The Spoonbill is of conservation concern in Europe and generally only spends the winter in Portugal.
However, in recent years, the Spoonbill has been found breeding in the sado estuary, and a small population has been established.
The Spoonbill has been found breeding in Europe and generally only spends the winter in Portugal.
The Spoonbill has been found breeding in Portugal.
The habitat with the greatest biodiversity in the estuary is the saltmarsh, which is of extreme importance for marine and estuarine animals, and serves as a nursery for many species of mollusks, crustaceans and fish.
Saltmarshes are formed by the deposition of mud around salt-tolerant or halo-phytic plants.
They fringe the banks of the estuary and conform small islands or islets.
In the spring, the shrubby vegetation of these islets provides the ideal conditions for colonies of little egrets, Spoonbills and Caspian gulls.
The flocks of Spoonbills and Egrets are sometimes mixed with the chicks of both species living side by side in adjoining nests.
Often, you can't tell where one ends and the other starts.
These islets provide an important refuge for the birds, as here they are far from terrestrial predators and can nest in safety.
Early May, there is already lots of activity in the colony.
This is the new generation of little egrets in the estuary.
Their appetite is insatiable.
While the chicks eagerly wait, the parents forage in the channels of the saltmarshes.
The little egret is a common sight in the estuary and can often be seen fishing at low tide.
Saltmarshes are endangered habitats. Due to the expansion of urban, agricultural and industrial lands, their area is greatly reduced and must therefore be protected.
Every year between summer and autumn, thousands of flamingos return to the Sado estuary from their breeding grounds in the south of France and Spain.
The population of the Sado estuary is the second largest in the country, with close to 4,000 individuals at the winter peak.
Most juveniles remain here until they reach sexual maturity at around three years old.
During that period, they gradually begin to disperse to other Mediterranean wetlands.
Flamingos are an icon of the Portuguese estuaries. Their elegance and the pink plumage exhibited by the adults will fascinate any bird watcher.
These long-legged birds join with flocks of hundreds of members and together form a group of thousands of individuals come wintertime.
Flamingos usually feed in the intertidal zone. Although when the tide rises, they turn to the salt palms to forage.
The length of their legs allows them to stand at various depths and enables them to choose areas with their preferred prey, which they collect with their specialized beaks.
Rice fields extend over most of the arable land of the estuary. An area of high agricultural production, the paddies have replaced much of the salt marsh.
These lands are watered by irrigation canals from upstream dams and are protected from the tides by dykes built along the river.
Despite their human origin, the rice fields support many species, especially during the growing season when the paddies are waterlocked.
Amongst the plants, the wildlife thrives.
No wonder then, with food in abundance, that the rice fields are filled with flocks of birds.
White stalks, spoonbills, several species of herons, and more recently, the glossy ibis.
However, one species is threatening the entire ecosystem, the red swamp crayfish.
An exotic invader, this voracious crustacean feeds heavily, particularly on sensitive species such as amphibians, and its burrowing activities can lead to damage of the rice crop.
One species that has increased numbers over recent years is the glossy ibis.
In the 19th century, the glossy ibis was common along the Iberian Peninsula, particularly in the south of Spain, but it declined significantly during the 20th century.
Fortunately, populations are now on the mend.
The bird's body and beak shape are very similar to those of sandpipers. In some regions, glossy ibis are actually called black sandpipers.
However, these two species are not related and belong to two different families. The glossy ibis is actually part of the spoonbill family.
Living up to its name, the glossy ibis shows a much more brilliant and gleaming plumage than their cousins, when the sun shines, the iridescent feathers shimmer in the light.
These waders are regularly seen in small flocks in the rice fields, feeding on insect larvae, small fishes, amphibians, and also crustaceans.
Their abundance in the estuary has been rising, and in 2012 they bred here for the first time.
This pair of kentish plovers seem nervous.
They are restless, running back and forth. A few meters away is the reason for their anxiety.
When alone, the chicks must rely solely on their camouflage.
The middle of a dirt track is a perilous place to live.
When they hear a call from their father, the young run to him for protection under his body and wings.
But this little chick senses danger and runs back to the nest.
Luckily this time it was a false alarm, just a small beetle passing by.
Still, the parents don't want to take any more risks and move the chicks to their natural environment, water.
The sandy soil surrounding the estuary is perfect for this colony of bee eaters to build their nests.
They dig tunnels that can reach two meters in depth.
Bee eaters migrate each spring from the savannas and arid areas of northern Africa in order to breed.
Of all our birds, these perhaps are the most exotic, with their vivid colors and charming sounds.
They fly effortlessly over the rice fields and agricultural land searching for prey.
Bee eaters, as the name suggests, feed mainly on bees and wasps, but they can also take other flying insects, such as flies and butterflies.
At this time of year, breeding pairs have on average four chicks to feed.
They must go back and forth to the nest all day.
When entering their nests, they are at their most vulnerable to predators, such as snakes.
So they must first check for danger nearby, and only then will they go inside.
This is the nest of the bee eaters.
The nest of the bee eaters is the nest of the bee eaters.
Some of the rarest habitats in the estuary are the freshwater ponds.
These pools are a great asset to the life of the estuary, as they provide the only freshwater in a vast expanse of saltwater.
The fauna here varies throughout the year, depending on the water level and the vegetation.
The dense reed beds are suited to shy, elusive species that cannot be found in the open waters of the estuary.
During the summer, reed beds allow the formation of colonies of herons, glossy ibises and spoonbills.
This is the largest colony of birds in the freshwater ponds of the Sado estuary.
The lack of suitable habitat elsewhere has created major overcrowding.
Now thousands of birds have made their nests here.
The marsh harrier.
This winged predator is an expert in scouting the dense vegetation, flying over in search of small mammals, amphibians and crustaceans hidden in the reeds.
It must be successful in the hunt, for it is not just feeding itself.
Secluded in the immense reed beds, its young are always ready for food.
However, the marsh harrier is not the only species hunting here.
This little egret is prey on the plentiful red swamp crayfish.
Its technique is to try to expose the crayfish, making quick movements with its feet in the water.
And it is a successful approach.
The Sado estuary is one of the most important wetlands in Portugal.
Being of international significance for biodiversity and conservation of endangered habitats and species, especially for birds.
Here, we can find around half of all bird species occurring in the country.
Human activities such as salt production and sustainable agriculture and fisheries are also of critical importance and contribute to the balance of this great ecosystem.
Between the sky and the tides lies this fascinating natural world.
It requires us to respect and to protect it, so that it remains a true wildlife sanctuary.
Thank you for watching.
Thank you for watching.
