21 Mar 2009

Ria Formosa - 11 Feb 1989

The Ria Formosa Natural Park is a remarkable area of marshes, lagoons, mud­flats, saltpans and sandbars, extending from 15km west of Faro, eastwards almost to the Spanish border. It is recognised as a wildfowl feeding ground of inter­national importance for such species as fla­mingo, spoonbill and many waders and wildfowl.

Created in 1755 by a great oceanic earthquake, the landscape of sand dunes, islands and bars to the open sea is still continously reshaped by tidal changes. During the 1870s, this whole area was leased to one family as a royal favour. When the lease ran out in the mid-1980s, the crown no longer existed and the state wanted the land. The family laid claim to it and there have been several years of legal, polit­ical and personal battles as to who should have what. However, since then, the Ria Formosa has been a protected nature reserve, despite the heart of it being under the flight path of Faro airport. The water here is still excellent quality, having managed to escape detectable contamination by industrial effluents, sewage dumping, agricultural and radioactive pollutants. The main industry, away from the tourists, is the traditional gathering of sea-salt. Except for the protected area at Ludo, there is considerable human influence on the area: the marshland and mudflat shellfish fauna is exten­sively exploited, and some of the offshore sandbars are already crowded with holiday homes.

We stop for lunch half way between Ludo and the Praia do Faro where we watch kentish plover and other waders and gulls. Then we visit Les Batty and his family ‑ friends of Ralph and Glenis. Les lectured at the university at Faro and, although his subject was oceano­graphy, he managed to include sea birds and saltpans in his work. He explains to us that many saltpans are being converted to fish farming tanks. As yet there are no bird problems on these fish farms and Les hopes to study the changeover and the effect on birds before the farmers suspect the birds as potential pests and used that as an excuse for more shooting.

At Les's suggestion we give Ludo a miss and carry on to the Castro Marim reserve, stopping to the see the salt pans at Tavira on the way. Salt extraction here is on a larger scale than we had previously seen and there are great white mountains of the stuff waiting to be transported away. There are few birds in those evaporation tanks that are almost dry, but those with water hold black‑winged stilt, avocet, godwit, red and greenshank, and even a couple of sanderling.

Half a dozen stilt feed in one part­icular tank, with others coming and going all the time. They wade in water just above knee deep, pecking things off the surface or off the bottom, frequently immersing their heads. Sometimes one gets into a rhythm of stepping and dipping. Mostly they feed together quite peaceably, but two birds are giving each other some hassle. One bird sits on the water as the other approaches, stands up when it has passed, then sits down again. When the second bird has moved on several metres, the first one jumps into the air and flies over it, appear­ing to threaten it, before land­ing a metre further along. Both birds resume feeding peaceful­ly, then repeat the process after a while.

04 Feb 1989 - Cabo san Vicente

We spent the night beneath the lighthouse at Sagres. No‑one bothered us but there were cars coming and going all night, or so it seemed, with night fishermen.

We breakfast to the sound of thekla lark in song-flight: the lark went up high and flew in circles, sometimes pausing to hover briefly in one place. It did not sing continuously but when the display was last properly finished, the bird plunged earthward with folded wings. There was no doubting its identity, since we had clear views of its pale grey underwing (the crested lark has an orangy‑buff underwing).

Black redstarts were also singing, but from the tops of rocks. Their ditties included a strange, unbird‑like, hissing sound.

While we were talking to the other campers (they were not into wildlife) a mouse appeared from amongst the hottentot figs. I put out our two Long­worth traps close by and caught it within five minutes ‑ we have frequently put the traps out at night but never caught anything. This beastie was a young male wood­mouse, and it posed for photo­graphs before being returned to forage amongst the figs.

Out at sea - a feeding frenzy of thousands of gannets, gulls, skuas, shearwaters and cetaceans. They disperse after a while then another frenzy starts up with cetaceans (they may have driven fish up to the surface to catch for themselves) and a dozen gan­nets. The dazzling white plumage of the gannets attracts more gannets to the fishing area, and other species take note of the signal too.

Skuas (bonxies from their size and shape) come in and sit on the water; then more gannets and balearic shearwaters, then gulls and more cetaceans. The skuas move up to the top of the stack of birds, ready to pounce on any unsuspecting bird hoping to get away with a meal. They often chase, three or four together, after a gull, grabbing its wings or tail, or just dive-bombing it until it drops its prize.

The rest of the afternoon is spent driving slowly along rough tracks looking for little bus­tards. We find lots of lapwing and lots of stones but no bustards.

03 Feb 1989 - Cabo St Vicente

Westwards from Portimao is a rocky coast known as the 'Barlavento' meaning wet and windy. The hilly coastal land becomes less fertile, and the population density decreases. The arid and windswept headlands of Cape St Vincent are composed of limestone rocks, weathered into a plateau and ending abruptly in overhanging cliffs some 80m high.

Apart from being heavily grazed by cattle and sheep, the headlands are relatively undisturbed by man and still hold plenty of botan­ical interest. The dominant plant is Portuguese cistus which forms low compact spreading bushes with extremely shiny sticky leaves. Few plants are actually in flower, but they include the yellow Calendula sufruticosa and the spiny Astro­galus massiliensis ‑ few plants have common Port­uguese names, let alone English. Hottentot fig covers much of the rocky ground.

At Sagres, strong winds of indeterminate direction swirl along the coast, and there is a heavy swell on the sea. Most of the birds over the sea are gannets, predominantly adults heading west. A couple of balearic shearwaters, a little gull, a kittiwake, and a few razorbills, some in summer plumage. Closer inshore are a few black-headed gulls, cormorants and shags, while lesser black‑back and herring gulls either fol­low the fishing boats or hang-glide along the top of the cliff.

The headland is populated mainly by black redstarts, linnets and meadow pipits. A first winter male blue rock thrush is busy catching bees in flight. It spends some time carefully wiping the sting off each bee before swallowing it.

Sagres is considered to be a good place to see thekla lark, a species very similar to crested lark, differing mainly in habitat and in the colour of its underwing coverts. A thorough look at all the larks today reveals only cresteds – even though our information says they don’t occur here!