Yesterday evening we drove to the Lauwersmeer in the north‑east of Friesland, another one‑time tidal inlet that had been reclaimed. It was closed off from the sea in 1969, leaving 5000 ha of tidal sandflats where vegetation was allowed to develop naturally, 2000 ha of heavier soils to be reclaimed for agriculture, while the original system of creeks and gullies made another 2000 ha. Within a few years over half of the sand-flats were covered with salicornia. With no grazing or mowing of the area, there was a huge stock of food for autumn waterfowl. Up to 65,000 wigeon, 60,000 teal and 50,000 barnacle geese took advantage of the bounty each autumn in the 1970s.
At the western end of the sluice gate that now keeps the sea out, a man‑made spit goes a hundred metres into the Meer and allows a view behind the woods and shrubs bordering the car park.
Things are fairly quiet, a hundred or so pochard roosting nearby, common and black‑headed gulls taking baths and preening, later to be joined by three great black‑backs and a half-dozen immature herring gulls. Two little grebes diving busily, two grey herons perched in small bushes carefully combing their feathers, while small numbers of other waterfowl quietly go about their business at the edges of the reedbeds.
Half a dozen tufted duck fly in and, as they come to a stop just beyond the pochard, a rather small brownish duck dashes out from behind the reeds to join them. If it was hoping for companions of its own kind it was out of luck. It looks familiar but we puzzle over its identification, and take copious notes on its plumage as it spends ten minutes thoroughly preening every feather it can reach. Then it takes to diving. It is a juvenile long-tailed duck, familiar because we had seen one before, but without any other species nearby for comparison we had not realised just how small it was. After a few more minutes this bird swims towards us, then takes off, flying low over the water but showing its pale belly and dark underwings as it flies in a series of s‑bends before disappearing behind some vegetation.
Meanwhile four brent geese fly across the meer, two goosander redheads (females and/or immatures) fly in to join the pochard, and pairs of shelduck are flying past. Then we hear barnacle geese flying directly above us, the low winter sun picking up the contrast of white belly and dark underwing. Other skeins of geese come and go in the distance and we can just make out a large flock feeding in a field about a kilometre away. Something disturbs them for they all take off and swirl around above the field for a couple of minutes before settling again.
We are getting cold, and thinking about leaving, when a Dutch lad walks over to join us. He does not have binoculars but seems quite knowledgeable about the local birds ‑ large ones at least ‑ wildfowl, gulls and robbery birds (raptors). He thinks we were too early for the huge numbers of geese, and are optimistic about sea eagles ‑ perhaps half a dozen pass through each winter and you may be lucky or may have to wait a few weeks for one.
We are still talking as we reach the car park; suddenly a first year female sparrowhawk flies around the bushes, low over the ground and close enough that we can see the barring on her chest, and her yellow eye, without using binoculars. In the bushes are blue and great tits, chaffinches, goldfinches, tree sparrows and a great-spotted woodpecker, each one a potential meal for a sparrowhawk.
Waddensee
On the other side of the sluice gates, which keep the water level in the Lauwersmeer to 85 cm below mean sea level, is the Waddensee, 8,000 square kilometres of shallow, intertidal mudflats considered to be one of the most important wetland areas in western Europe for wintering and migrant wildfowl and waders. It is sheltered from the worst of the North Sea storms by the Friesland Islands, which run parallel to the mainland coal. The Dutch section of this sea comprises about fifty per cent tidal flats (or waddens), the rest being tidal channels and shallow water. Smaller sections belong to Germany and Denmark.
The area should be fringed by saltmarsh, but only 87 square kilometres of this were left after centuries of reclamation. Now about half of the flats and most of the saltmarsh were private or state nature reserves, and the major threats were pollution (PCBs have been of particular concern in the last two decades) and disturbance through recreation activities and military training.
Autumn migration here starts with the arrival of spotted redshank in the second half of June; then grey plover, knot, dunlin, bar‑tailed godwit, curlew, redshank, greenshank and turnstone in July; oystercatchers arrive in August followed by wildfowl from September onwards. Geese and shelduck arrive in October and sawbills in October and November. Some six to eight hundred thousand birds stay for the winter, mostly eider, wigeon, oystercatchers, curlew, knot and dunlin.
All of the sandy Friesland Islands have important breeding sites or high tide roosts, and many have nature reserves. Opposite the Lauwersmeer is Schiermonnikoog, the smallest of the five inhabited isles, with dunes, beaches, woods, saltmarsh and freshwater lakes. It is famous for its high tide wader roost. The fifty minute ferry service from Lauwersoog, took foot passengers only. (It is actually possible to walk across too! It's a bit like crossing Morecambe Bay, you must have a guide to do it safely.)
As we look across there are many gulls loafing on distant mudflats. On the water are large numbers of eider, one of which surfaces with a crab and is then harassed by a herring gull until she drops it and dives to escape the unwanted attention. Some 200,000 eider winter on the Waddensee, and for most of this century some have remained to breed on the Friesland Islands.
Two snow buntings announce their presence as they battled with the wind. We battle back to the shelter of the van.
Geese II
We drive past a field of golden plover, about 1500 of them playing stop-start games with imaginary traffic lights as they searched for food. A few dozen lapwing wander amongst them, often chasing a goldie, perhaps for a morsel of food, or just being bullies.
In the next field are a thousand or more barnacle geese. They, and the plovers, take to the air above their respective fields when a plane passes over. The goldies landed back where they had been, but the barnacles moved to a field further from the road.
All the geese grazed in one field as if they were a domestic flock surrounded with wire netting. Barnacle geese, with their small bills, prefer short grassland that is regularly cut or grazed in summer. They like the fine leaves of meadow grasses, but feed principally on stolons of clover (starch rich storage roots), probing their short bills into the mat of grass stems for the stolons lying beneath. So when a field of ideal food is found, they all descend on it and ignore the surrounding land for a while.
Geese of all species commonly graze young sprouts of autumn grown cereals, moving onto such fields as soon as growing shoots are a few centimetres high. After a few days a field appears brown, but the crop is not destroyed ‑ the shoots sprout again, often more strongly than if geese had not been there (sheep grazing and mechanical rolling have the same effect). If grazing takes places later when the plants are taller, the crop can be set back permanently but, fortunately, geese are less attracted to taller growth.
When geese have finished with arable crops they switch to grass. As the grass is hardly growing at this time of year, they cause little damage, but it is common practice for farmers to fertilise a few fields each winter to encourage early growth. Such fields look brighter green and the geese recognise them as good feeding, then there is conflict between farmer and goose.
It is not easy to assess damage to crops; experiments use domestic geese penned on plots to simulate effect of wild flock. The results show no measurable differences when the crop starts growing again, even when the flock feeds at a density unlikely to be reached in the wild. Apart from the damage mentioned above, the crop can be puddled into the ground in prolonged wet weather, and geese can strip the unripe seeds of grain if they arrive very early or if the harvest is very late.
Geese spend about 90% of each winter day feeding, taking about 650 ‑ 800 grams (1.5 lb.) of fresh vegetation each per day, though their relatively inefficient digestive system absorbs only about a third of it. Perhaps the birds should be thought of as fertiliser production lines, for the partially digested vegetable waste quickly breaks down and is reabsorbed into the soil.
The Dutch government recognises that farmers do have problems as a result of the protection given to geese, and as geese numbers rose from 100,000 in the 1960s to over 600,000 in the mid-eighties, so the compensation paid to farmers also increased, from ,1500 in 1974 to ,758,000 in 1988, and is still increasing, some people think, to a ridiculous extent. The money for these payments comes from shooters' licence fees. (refs: Bruinderink 1989, Monnobar & van Erden 1990)
From Oostmajorn we walk along the main dyke around the Meer and come across another field of barnacle geese. There must be a couple of thousand at least, though counting is next to impossible when one was faced with such a seething mass. They keep up a constant bickering, threatening any neighbour that comes too close. The birds on guard duty (usually males) watch carefully as other wildfowl flew overhead. Bewick swans pass in groups of five to twenty, their calls announcing their presence above the clamour of the geese.
Other skeins of barnacles come in, the groups getting larger as the light fades. Eventually the cold gets the better of us again and we leave. Suddenly the noise increases and half the flock take to the air in a swirling cloud, victims of their own nervousness, then settle back to feed again.
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