Where do the majority of woodcock that migrate to Ireland come from?
Woodcock which winter in the Western and Southern parts of Europe come from Scandinavia, Central Europe and Russia. The migratory flyways follow a general direction North-East - South-West. So, the majority of woodcock that migrate to Ireland come from Norway and Sweden. This has been proved by ring analysis.
What prompts the migration of woodcock to Ireland is it climate change or is it inherent in the bird?
As for all the migratory birds, this phenomenon is inherent in the bird. It is probably the result of a genetic programme which "indicates" the direction and the travel duration to the bird. However, the date of departure is linked to the duration of the daylight. I would add that amongst the woodcock populations some are totally sedentary, some are partial migrant and others are long migrant. In winter in Ireland, you have sedentary (which breed in Ireland) and migratory woodcocks at the same time.
When does migration start, in what month, how regular is this?
I take into account only the woodcocks which winter in Western and Southern Europe. The birds which come from the further breeding sites (Oural mountains) begin to migrate in mid-September. In North-West Russia, they start in the first decade of October. Usually the first migratory woodcocks reach our countries (France and Ireland) at the end of October but the peak of migration occurs around mid-November. So, you see that the migration may last two months. From the ringing analysis, we know that a woodcock can travel 500-600 km in one night. So, of course, the birds stop during several days during this travel. They need to stop for resting and storing fat which is a source of energy. These are the average dates. But many factors can affect migration, especially the weather conditions. If it is warm and/or if strong winds hamper the flight, the migration can be delayed. If an early cold spell occurs, the migration can be advanced. Nothing is strictly defined in animal behaviour !
Is the migration continuous or in large groups phased over a specific period? If it is in groups, what is the age profile, are groups mixed age birds or are groups comprised of young birds in one group and older birds in a later group?
Indeed, the migration is in groups of 5-6 birds. As far as we know, these groups seem to be randomly made and you can have young and/or adults, males and/or females in the same group. These groups don't correspond to a family, parents and their young. However, there is a general tendency in the succession of classes of age and sex. During the autumn migration, the young are more numerous in the beginning and the adults reach the wintering sites last. Likewise, the females arrive before the males. This is a general rule, but of course you can find some adult male at the beginning of the migration. The opposite is observed during the spring migration : the adults reach the breeding sites first.
If the first migrants are first-year birds, will they fall to the same area as the parents who will follow later?
an important family dispersal for woodcocks, especially for the birds
which breed in the most northern part of Europe. This dispersion is less
important for short migrant woodcocks. So, we can say that it is very
unlikely that young and parents winter together in the same wintering