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Since a few days, we have got back he midnight sun again in Tromsø, N. Norway, where I have lived since 1973. But spring is late this year: our garden is still 3/4 snow-covered, the birches are still bare and I have not yet heard
the Willow Warbler, our most numerous song bird.
As several people has asked me how birds and birding are in winter in Tromsø, when it is mostly dark, I'll give an impression here. Please let me know, if I mail too often these days; being more or less isolated gives one more
time for such activities.
Tromsø in winter--birding in the dark, part 1
Tromsø is at c 70* N, and with c 75 000 inhabitants the largest town in N. Scandinavia. Because of the Gulf Stream,
we have a forest of mainly birch trees (and pines in the inland), instead of ice or bleak tundra, as everywhere else at this latitude. The town is situated on the island of Tromsøya, and the sounds surrounding the island form the sill of the large Balsfjord.
Between us and the open sea there is the large and high island of Kvaløya, so that by road it is c 50 km to the outer coast. The island itself is not very high, maybe 100 m, but the surrounding hills on the mainland and Kvaløya reach 1200 m. My house is at
the south end of the island, at c 45 m o.s.l., and close to a remnant birch forest with much planted spruce, Folkeparken; I walk through Folkeparken on my way to Tromsø Museum, where I worked for 40 years and still have a desk and do research on my specialty,
the amphipod crustaceans. I am now 83.
Being so far north, we have a long winter, and snow half the year (snow depth, now, 26 May, is 80 cm(!), but this
is a late year), but because of the open water around, the winters are not very severe, with temperatures rarely falling below -17*C (in the inland it easily can get - 40* C). All the cars here have summer- and winter wheels, and they shift to winter wheels,
usually with studded tires, in October, shifting back in May. I also use 'brodder' under my shoes for most of winter; they are especially useful in the increasingly frequent periods of Atlantic depressions with milder temperatures, leading to very slippery
and icy roads and paths (Without these periods, we would have had almost 4 m of snow this winter!).
Another major factor between our winters and yours is the absence of daylight in mid winter here; the sun is not
visible from late November to late January. With the reflecting snow on the ground it is usually possible to walk the unlighted paths in Folkeparken during the day, but birding in winter is no easy task: the icy roads are hard to drive (in fact, I don't drive
at all in winter anymore) and there is very little daylight.
So how do the birds cope with all this? Most simply by doing what a popular song here says: 'The birds come to their
senses and fly south': they leave us in autumn and come back in spring. Some, like the Arctic Terns, almost overdo this by flying all the way to the Antarctic, and swallows, cuckoos and Willow Warblers winter in S. Africa, but many species do not migrate further
than South or even Western Europe. The species that do stay here in winter I have divided into several categories:
- Seabirds.
For them there are no problems of ice and snow, as the water remains open. On the other hand, the dark may well be a problem for species such as terns that hunt by sight, making it impossible to remain here in winter. We won't talk about them further,
just remark that in winter we have here several species that nest even further north, and only can be found here in winter. Good examples are the King Eider and the Yellow-billed Loon (White-billed Diver for some).
- Shore birds. There is often ice on the shores in winter, and many if the intertidal invertebrates also
migrate to deeper water in winter, so the shore is a difficult environment in that season., and most shore birds leave us. A few of the hardier gulls, such as the Herring Gull and the Great Black-backed Gull can be seen here all year (But it looks like as
if ours migrate and the winter birds are breeders from NW Russia). And there is a single shorebird that apparently has overcome all these problems; that is the roly-poly Purple Sandpiper, that seems impervious to the cold and always able to find the periwinkles
they feed on.
- Freshwater birds. All freshwater here freezes over for many months on end, so these birds all have to
leave, unless they can change over to the open shore, as the Grey Herons and some few Mallards do. Another small exception is our national bird, the Dipper, where part of the population survives the winter up here at some rapids, that never freeze completely
over.
- Ground feeders. Just as with the freshwater birds, they all
have to leave in winter, as the ground is snow covered for
months on end. A few Woodcocks try to winter on the outer islands, but they often are found dead.
to be continued
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