Hi GG,
Just looked at this tube clip of bees on hazel pollen. Do you know the location? - the geographical context is relevant. I see buildings in the backlog round, sun and calm conditions. Here in the wet and windy west of Ireland, hazel puts on catkins during Feb when my bees are largely inactive and there is overlap of flowering with willow, especially in March, and it offers more rewarding forage.
Alan.