Another autumn is coming to an end

By the end of October most birds have left Finland and the few that remain are preparing themselves for the winter. But something is still moving. During the last two days of October in Hanko I still saw good numbers of Long-tailed Tits (they counted more than 1200 at the Bird Observatory on the 30th!) and Waxwings, while small groups of Common and Parrot Crossbills were still flitting around. Most of the thrushes had disappeared by mid-month, but an influx of Blackbirds, a strictly nocturnal and later migrant, suddenly filled the gardens about a week ago. Other late autumn migrants, in fact the last ones to arrive, are Bullfinches, which obviously have had a good year, Greenfinches and Yellowhammers, all of which will stay, at least partially in Finland.

At sea things are different. Although most ducks have gone by now, the Goldeneyes are only reaching their peak, with flocks numbering several hundred strong, and the Long-tailed Ducks, coming here to winter, are only just building up in numbers. The recent cold spells iced the lakes of the north, causing the Whooper Swans to leave their northern breeding grounds. Hanko is a great place for Whoopers in late autumn, with hundreds staying to feed in the shallow inlets. They stay until the sea eventually freezes over, forcing them to move to milder climates. Late autumn is also good for White-tailed Eagles, with the breeding population being augmented by birds from further north and east. At this time of year it is in fact the most often seen raptor along the Finnish coasts and it is not difficult to see more than ten in a day. Other raptors still hanging around are Goshawks, but only in small numbers, and if you are lucky you may see a Golden Eagle.

Nutcrackers are also a feature of the autumn, and although this fall witnessed no big influx, birds are still showing well. Southwestern Finland has traditionally been inhabited by the thick-billed nominate subspecies of Nutcracker, which is depending on Hazel nuts for its living. Hazel has a rather restricted range in Finland, and consequently the Cracker has also been a localized bird. Every now and then Finland is reached by huge invasions from the east of the thin-billed Siberian subspecies, which then tends to hang around for a while before disappearing again. However, already in the seventies Nutcrackers were reported to breed also in eastern and northern Finland, well north of the range of Hazel. These were thin-billed Siberian crackers relying on different exotic pines for food. The situation with the two forms breeding almost side by side has now been going on for decades, but as far as I know, this has not been studied in detail. Looking now at the autumn migrants at Hanko, I certainly get the feeling that many birds cannot be assigned to either subspecies. There are clearly thick-billed and thin-billed birds, but many, if not most, are nicely intermediates in all respects. Traditionally the thick-billed birds were not supposed to be migratory at all, but now we see them moving together with the thin-billeds. Traditionally the thick-billed nominates were supposed to rely on Hazel, but two days ago I photographed a territorial pair in Hanko (which by definition should be thick-billed) collecting seeds from the cones of Macedonian Pine (!) to be cached for the winter. What I’m trying to say, is that we probably have an intergradation of the two subspecies over large areas, which used to be inhabited by thick-billeds in the past. The birds don’t only look intermediate, but they have also widened their ecological niche, by feeding on exotic pine species, such as Cembra and Macedonian. More studies are definitely needed.

Finally, driving back home from Hanko yesterday afternoon (31st Oct) I spotted a Hawk Owl on a wire after some 15 mins of driving. As such, this is nothing special in a year like this, when they have been seen in above average numbers since late Aug. However, 30 mins later I saw another one, just by the road, and stopped for a few shots, although it was getting late and the light was not good. And, as if two wasn’t enough, a third Hawk Owl on a wire just 5 kms from home rounded off the day nicely. This is the only day since Oct 1976, when I have spontaneously found 3 Hawk Owls in a day, so probably we are living a major influx.
But, Oct 1976…. that was a hell of a Hawk Owl autumn, which for sure won’t be matched now, perhaps never? During three weeks in Oct-Nov 1976 our one-car team trapped 56 Hawk Owls, with 17 handled and ringed in the best day! That is a record difficult to beat.