The winter birds include a good number that come from Northern Europe to escape the harsher winter weather. These include divers, grebes, cormorants, herons, spoonbills, geese, ducks, waders, gulls and terns.  

The best way to see the marshes is to follow the established route that runs over the docks of the Marsh of Bengoa, north of the town of Santoña and along a road that runs parallel to the C-629 road. This easy 2.3km route can be traveled in about 2 hours – depending on how often you stop to look at the birds! And then there are other, longer routes – we also took one of them and made a whole day of it.

Three fairly short rivers flow into the bay at Santoña and Laredo, and saltmarsh is creeping onto the mudflats exposed at low tide. Sheltered from Atlantic storms by the limestone massif of Monte Buciero at the harbour mouth, the bay attracts sun seekers in summer and flocks of migrant wildfowl and waders in winter.

Spoonbills (above) stop here on migration, and shelduck have taken a liking to the place in recent years, though there were none of the latter to be seen today. The marshes are the principal site on the north coast for grey plover, dunlin, greenshank and curlew. The most numerous species that we saw was wigeon (top photo) – thousands of them – settled quietly on the water.

We parked in Santoña and walked. About half way along there was an area surrounded by a dyke and partly drained.  It had a few healthy-looking ponds and willow scrub in the wetter part

Eucalyptus

A small eucalyptus plantation occupied the drier area. The trees were regenerating, but there was no under-storey since the ground was carpeted with slow-decomposing eucalyptus leaves which inhibits the growth of other species.

Eucalyptus was introduced to Europe in 1804, within a few years of the discovery of Australia.  It was soon found to grow well on deforested land where the soil was so thin and badly eroded that few other tree-species could find sufficient sustenance. Throughout the nineteenth century it spread on eroding, near-desert, lands around the Mediterranean, serving as windbreaks, providing welcome shade and stabilising the soils. It is only relatively recently that its use in forestry has become important, the wood is ideal for pulping to make paper, and on less impoverished soils the trees grows very quickly.

Like most introduced species, the eucalyptus has a reputation for being no good for birds: and the few birds that we did see or hear were well-hidden by the evergreen (or should that be ever-grey) leaves.

Fishing – the human side

While the tide was low there were a number of people out on the marshes, variously fishing, digging or probing for whatever was there. We watched a couple of fishermen under a bridge. They baited a wok-shaped basket with a sizeable piece of fish.  Then they slowly lowered the basket, with the aid of a forked stick and a rope,  into the water and laid on a ledge or mudbank. After a few minutes it was slowly pulled out of the water and the catch of crabs and crayfish was emptied into another wicker basket.  Traditional methods of fishing are still allowed here since the marshes were declared a natural reserve in 1992.

The estuary of the Asón (the largest of the three rivers that flows into site) is also an important spawning/fishing area for sea ​​bass, red mullet, sea bream, sole and eel and Atlantic salmon. Shellfish are farmed here, and the development of the canning industry for anchovies and sardines is part of the economic activity of this area.

Birdwatching

It was mid-December, and our day at the Santoña Marshes was grey and murky with neither wind nor sun, but some drizzle in the afternoon.  At least we didn’t have to contend with the glare of the sun bouncing off the water

The tide was coming in and bringing with it a juvenile red-throated diver (above) and an adult great northern diver which we were able to study at much closer than usual quarters. The red-throated looked small and finely built compared with the heavy angular great northern. The latter swam mostly in a hunched posture, but then took to preening, followed by a fishing session. For this it swam around with its head and neck stretched along the water surface, then dived, sometimes coming up with a crab.

Four red-breasted mergansers flew in and spent most of the time vigorously stirring up the mud and shallow water. Eider and scoter also moved up-stream, some of the female and juvenile scoter looking almost chestnut in colour.

An adult Mediterranean gull roosted on the mudflat, then became active as the tide disturbed it. It walked a few metres and picked up an amorphous lump from the mud, took it to a nearby puddle and washed it thoroughly several times, then shook it vigorously for a few seconds before swallowing it whole. This species’ winter diet consists mainly of molluscs and marine fish.

Two little egrets fished close to the shore: one moving slowly and deliberately, stirring up mud with its foot, the other more energetic, rushing from side to side and flapping its wings to disturb prey. The first one seemed more successful. Later a dozen egrets joined a feeding frenzy of gulls, cormorants and herons. At high tide they all roosted together on a half-submerged wreck.

Among the waders common sandpiper and whimbrel were of particular note as we were now in their wintering areas. Some of the bar tailed godwit had cinnamon plumage on their necks, breast and scapulars indicating they were juveniles.

Out on the open channels, about forty black-necked grebe (above) were roosting or preening. As the tide brought them in, they dispersed into smaller groups and began feeding. Often a group dived together, leaving the water empty. They were quite noisy, calling to each other with high pitched whistles. If a bird surfaced alone, it sometimes got quite frantic, whistling loudly and paddling around to find its mates. Their rather contrasty plumage made the little grebe look quite drab.

A peregrine flew in, calling, and settled atop an electricity pylon to watch the world go by. We made our way back to the camper through drizzle.

Resources for visitors

The local tourist website has more information about accommodation etc, and a down-loadable leaflet about the reserve.  However, it is now available in Spanish only.

Brittany Ferries and others go to Santander – 15km to the west and the closest port to Santoña.  There is the chance of seeing cetaceans and seabirds as you cross the Bay of Biscay


Wikitravel For information about travelling in Spain