For years, I have been wrong (and have been misleading readers) when I have said that the Pine Grosbeak is a locally irruptive species.
An irruptive bird is one that breeds in the north, but, occasionally irrupts in large numbers to the distant south. I had been persuaded that the Pine Grosbeak was one of these irruptive species by a number of websites that labelled it as such, plus the fact that I only saw it now and then in winter months. It all seemed to fit. But, I was wrong.
Certainly, the Pine Grosbeak is irruptive on the eastern half of North America, and websites based there proclaim it as such. But, these sites are regional (without saying so). In the western mountains, the Pine Grosbeak is, not irruptive, but a permanent resident. It is an altitudinal migrant: breeding in the high country during the warm months and sometimes descending to the valley bottoms in the cold months.
Today, I watched a few Pine Grosbeaks feeding on saskatoon berries.
This bird played the contortionist to get at the berries.
A male (top) and female Pine Grosbeak feed.