Musings on Grosbeaks

Most pictures of Pine Grosbeaks are taken of them munching rowan berries to extract seeds. This is not because it is where you always find them but because it is where it is easiest to take close photos of them.

This year they are spending just as much, if not more, time feeding in spruce and to a much lesser extent pine trees. There is a common misperception in Norway that they eat the seeds from the cones (like crossbills) which may well come from their Norwegian name, Konglebit, which literally means cone bite. However, it is not the plentiful cones that attract them but rather the small buds. I have also seen them eating buds on deciduous trees such as birch.

In the invasion of 2021 the birds were nearly just seen in berry trees as they also were in 2019. These were both good berry winters but siginficantly less than this year such that the birds were more concentrated and eventually forced into urban areas whereas this year they can still find countless berries everywhere. It therefore seems strange that they would spend so much time eating buds on coniferous trees this year but maybe there is an especially abundant crop of these too?

In the invasion of 2012 there were no berries when the birds turned up (slightly later than in the three subsequent invasions) and here I saw them nearly exclusively in spruce.

Grozzas are significantly easier to find when feeding in a low and leafless rowan tree rather than high up in a dense spruce which perhaps also explains to some extent why they are so frequently observed in rowan bushes. But there is clearly something else going on. In the years when they have come into urban areas (as these are the only places where they can still find berries) they could have remained in the forests eating spruce buds so maybe their ideal is a mixed diet but when berries are in a low supply but still available they will feed on these as long as possible which can lead them into urban areas where there is little or no access to spruce.

This video shows birds from the same flock feeding in spruce, rowan and pine:

male Pine Grosbeak (konglebit) nipping off a tiny brown bud from a spruce

food would appear to be much more abundant on the rowan trees

look at the berry juice on the bill

they often just slice the berries in two to reveal the seeds and if you see berries like this on a tree then it is a good sign that Grozzas have been there

here eating buds on a pine tree