Wednesday, March 31, 2010

Rain Chasers

Waterbirds are now gathering in the marshes of the Guadalquivir to breed. They come from diverse sources as these images show

there are year-round residents like the Little Grebe (above) and the Coot (below)

then there are migrants that have come from tropical regions of West Africa, like the Purple Heron (below)

Night Herons (above) also move in from the south, from tropical West Africa, only a small number remaining here in winter

Some Spoonbills winter in Senegal but they may be belong to the breeding population in Mauretania. But Iberian birds may join them some years. The key to success in these wetlands is the ability to change behaviour from one year to the next. And the bad season here is not the winter but the dry summer, from July to September. It is then that the wetlands are vacated, many birds moving south into Morocco and many more crossing the Sahara Desert. They arrive in countries bordering the Sahara (Mali, Niger) at the start of the wet season. With the onset of the dry season in the tropics, they return north to hit the fresh bout of rains that usually reach Iberia in October.

Some years the autumn rains arrive late, or they hardly make a presence. During drought years many of these migrants hardly make their presence felt. Some arrive but soon depart if feeding conditions are insufficient for successful breeding. But when the rains come they make the most of it, producing offspring before the summer drought arrives in July.

Burst of waterbird activity with the arrival of the rains

The White Stork, until recently, behaved very much like the migrants I have described. Many still do. The Iberian birds migrate south in July and early August, crossing the Strait of Gibraltar in huge numbers. They cross the Sahara and arrive in Mali, Nigeria, Upper Volta and Ghana at the start of the wet season. Then they start to return across the Strait of Gibraltar in October and continue to pass into January by which time the southern birds are on the nesting sites. West European storks pass later in the spring. 

But in the past two decades many White Storks have changed their behaviour. They have become resident and manage to cope with the summer drought by living off open refuse tips where they find sufficient food.  You can always tell them from the others as their plumage is usually badly stained. The White Storks in these photographs are now with eggs. They are birds breeding in the marismas and appear not to be regular visitors to such tips as their plumage is immaculate. They are among the early arrivals from Africa and are now well established in the breeding grounds.

Black Storks (this one photographed on the 12th February) are scarcer than White Storks, although numbers have increased significantly in recent years. They don't frequent rubbish tips and most are migratory although a few winter in the marismas. They don't breed here but pass through and stop to feed. Curiously, Black Storks are more widely distributed than Whites, breeding across Eurasia into the Far East. The White Stork, on the other hand, is practically confined as a breeding bird to the Western Palaearctic.

Tuesday, March 30, 2010

Footprints in the sand

Moving away from the marsh, towards the Atlantic coast the landscape of Doñana changes abruptly into a tangle of Mediterranean shrubs with scattered cork oak trees

Above: pajarera with Spoonbills and other waterbirds giving way to shrubland 

This place is a favourite for Wild Boars (above and below) which can hide in the tall vegetation and dig for roots at leisure

Black Kites hunt from perches (above) while passing Bee-eaters sweep the air for insects (below)

Herds of Fallow Deer graze in the safety of cover

Towards the coast shifting sand dunes begin to take over between the flowering Halimium

Stone Pines cope best with the shifting sand and replace the oak trees

But the sand wins in the end, surrounding the pines into traps known here as Corrales

...and eventually the pines succumb. This photograph shows the crown of the tree. The rest is under the sand, yet the tree clings on for life

death on the mobile dune

"between the devil and the deep blue sea" - pine wood with killer dunes in front and the Atlantic behind

but there is life here, even though it may not be obvious. Hares leave their footprints in the sand

that keeps the raptors interested, soaring high above the ground in search of prey. Black Kite and Booted Eagle (above), Red Kite and Short-toed Eagle (below), Buzzard (lowest)

where the water table is high temporary pools and bogs form (above) and in more permanent situations they become seasonal lakes (below)

...and the footprints in the sand give away a hidden presence: ducks, herons, stone curlews, deer and boar have all passed through here earlier in the day

A Weekend in Paradise

With the record amount of rain this winter I was keen to see what impact it was having on the wetlands of the region. There is no better place to go than the quintessential Doñana. It is a real privilege to be able to spend time in these marshes, away from civilisation, and get a real feel of what have once been a network of wetlands linking Europe and Africa. Dawn (above) across the vast flatness of huge marshland is undescribable. Here Night Herons return from a night's feeding activity and Grey Herons are starting their day.

The view across the marsh from the elevation of a watch tower (above) is spectacular. I have never seen it like this, not even during the wet 1995-96 winter.

There are waterbirds everywhere, and in large numbers, like these Night Herons (above). Many birds are returning from West Africa and there is so much water that some are delaying breeding until the levels are right. Even so the famous "Pajarera", an emblem of this place, appeared to be in full swing especially with White Storks, Grey Herons and Spoonbills

Pajarera (above and below)

Migrant waterbirds were also coming in from the south to breed. These included Collared Pratincoles, Squacco and Purple Herons (below)

 Grey Heron in flight

Grey Heron and White Stork hunting in shallow water

White Storks are now with eggs (above and below)

 Night Herons (above and below)

Local waterbirds, like these Little Grebes (above and below) are on eggs too and are highly territorial, chasing each other over the water

Red and Fallow Deer (above) are making the most of the fresh growth, feeding on the edge of the marsh amidst a riot of colour

Tortoises are also active along the marsh edge, known here as La Vera

Spoonbills and other waterbirds commute up and down La Vera between feeding grounds and nest sites

This activity attracts the attention of many predators. Red Kites (above) patiently patrol La Vera in search of frogs, small birds and rodents

Marsh Harriers (above) are opportunistic thieves

Viperine Snakes (above) are on the lookout for frogs

the local horses also feed along La Vera

Inland, pools, ponds and lakes (above and below) have appeared on usually solid ground

With the rising temperatures, now reaching 24C in the middle of the day, swarms of tiny mosquitoes and gnats are emerging along with dragonflies, large beetles and butterflies - a larder for insectivorous migrants arriving to breed

The swallows that have been coming in since late January have no shortage of mud for nest building

The colourful Bee-eaters were finally back this week, actively hawking for insects. Many more will move north in the following weeks

We'll continue to look at this wonderful paradise in the following posts