Godwits back from their incredible flight soon

Press, Volume CXV, Issue 33965, 4 October 1975, Page 11

Godwits back from their incredible flight soon

< By

KEN COATES)

The godwits will soon be back in their hundreds around the Sumr. estuary. They will arrive hungry, travel-scarred, and exhausted after the incredibly long migratory flight from Alaska or Siberia, spanning almos half the globe.

Called the kuaka by the Maoris, the long-beaked and long-legged Eastern bar-tailed godwit — to give it its full European name — appears in motif form on every N.A.C. aircraft. But few Boeing jet passengers give the bird a passing thought. In summer godwits are plentiful in their thousands around the shores of harbours, estuaries and river mouths in both islands.

About the size of pigeons, though plumper and with longer legs, godwits have speckled brown plumage, and distinctively barred tails. Their feeding grounds are tidal mudflats and sand, and in summer the birds stoke up on small Crustacea, worms, shellfish and vegetable material. Tilted beak They probe the mud with their black, slender beaks,

which are tilted slight!; upwards. Termed waders they do not swim on the water as gulls do, and while in New Zealand they are not seen on grass. When the tide covers their feeding grounds, the godw'its gather in certain places — the Maoris who hunted them as food called the spots puta — generally towards the coast. Here they rest until the flats are clear again. In this way they regularly and swiftly perform their routine flights from ocean beaches at high tides to lagoons and back again. Must be fit Tn a sense, they are in training, in the same way as athletes preparing for a marathon; they must be superbly fit for the gruelling journey ahead. A Christchurch woman who lives at Mount Pleasant overlooking the estuary has become keenly interested in godwits. She is Miss Norah Finn, a retired nurse, who has even made a couple of visits to Alaska to seek out the birds in their northern habitat. Hormonal change Because they are so difficult to tag or band, there is not a great deal known about the migration of godwits, said Miss Finn. But she has noted changes in the birds’ colouring as the time for

them to fly north approaches. “They get a hormonal change in their bodies," she said. "The females’ feathers become bright and the male has a rustcoloured breast." In some strange way the godwits know they must leave New Zealand’s shores. Thousands congregate in the far north, at Parengarenga Harbour and at Farewell Spit at the north of the North Island. Unknown guide It is in March that the godwits finally head off north. They fly swiftly across the Pacific, resting on islands, including Fiji, on the long haul. The mysterious process by which the birds know which direction to take is not fully understood; some experts think their built-in radar systems are guided in some measure by the stars. Finally the tired godwits reach the long chain of the Aleutian Islands, but their six-week journey is not yet over: their final destination is the bleak tundra of western Alaska and northeastern Siberia, where they join millions of other mi-

gratory birds from other parts of the world. The Arctic summer is short, and with the disappearance of snow and ice in late May or early June, the godwits display an urgency in making a nest and raising their young before the snow, cold and silence of winter again invades the tundra. Miss Finn flew to Alaska in 1970 and 1971. Studying the godwits through her binoculars prompted her to wonder just how many of these long trips a godwit makes in its lifetime. She wondered whether they always flew by the same routes, and whether they returned to the locality from which they left. Tracing flights “1 wanted to find out whether the main migration is to New Zealand, as is suspected,” she said. Placing a band around the leg of a bird is the usual method of tracing flight and of finding answers to this kind of question. “Godwits are too difficult to band in New Zealand,” said Miss Finn. “Herding them into a fine net on the mudflats would

be the only possible way of catching them. “In the mud of the estuary, the wild things would get so mud-covered and panic-stricken, the results would be disastrous.” So Miss Finn decided to try to band some godwit chicks in Alaska. She went to Nome in 1970. and searched for nests, usually concealed between clumps of bunch grass. The nest is usually a depression in the moss or lichen. The female sits on the eggs while the male bird keeps guard and meets any intruder with great ferocity some distance away. The nests are difficult to find. This is some protection against, marauding jaegers, fork-tailed, gull-like birds, which will swoop on eggs or chicks. Godwits have a Jekyll and Hyde quality: while in New Zealand they are shy and elusive, flying away if one approaches too near. But when nesting and raising their chicks, they become most aggressive. Banded chick There were few godwits in the area Miss Finn first visited, but she did manage to band one chick. She returned the following year after making contact with the American Fish and Wildlife Service. This time she flew to a settlement called Bethel, and then to the abandoned village of Old Chevak, where there is a wildlife refuge field station. Luck was against her again. “I stayed in a camp in that remote place with a whole lot of men — not that I minded that,” she said. Late spring “I got there in mid-June, but because spring was late that year I did not even find one godwit nest. 1 could not wait any longer than three weeks. It was most disappointing." Miss Finn is trying to arrange a visit to Siberia,

to where, she thinks, most of the godwits migrate. But although she has written dozens of letters to the Russian authorities in the last 10 years, the reply has invariably been that there are no bird-banding expeditions to Siberia in the meantime. Godwits lay their eggs usually during late May and the beginning of June. The young birds are flying by the middle of July. They wander northward, becoming adult and independent, and begin their southward migration with the main flocks in August Some authorities have written that the godwits return through Japan, China, the Philippines and the Malay archipelago to Australia and New Zealand. But others have evidence that the main migration route is further east — over the south-west Pacific, well east of the Solomon Islands. By this time of the year, the long and arduous sixweek flight south is almost over. But again there is no great cloud of birds to be seen in the sky marking their return. Quiet return As Miss Finn puts it: “Quietly they return and one day you notice them back in much greater numbers around the Sumner estuary. The godwits are back.” They are dowdy and bedraggled compared with the godwits which have stayed for the winter. Just why a proportion stay behind is not known. Miss Finn says they are immature or perhaps sick. Perhaps they never make the long trip to perpetuate their species. Fortunately godwit numbers do not seem to be declining, and it seems that as long as there are mudflats and food they will continue to come and go with the seasons — right at Christchurch’s back door.