With the number of individuals over time bernikli Canadian increasing all the time. However, they have started after some time cause problems for farmers. In some countries, even the birds attempted to emigrate to places where there will be too burdensome. In general, these ideas do not end in success, however, resulted in a wider area of occurrence of these geese. The reason for this was mainly to the fact that they rozmnażały with unusual speed. In western Europe, they live only a few large species, which in some way could prevent the excessive number of bernikli. Alternatively, they fall victims of their only day-old chicks, because adults are too strong to overcome.