I see the odd wild one out ferreting but usually they arrive here in their thousands around mid January from Scotland & the UK and feed on alder seeds close to river banks and when this food is depleted they hit the peanuts in garden feeders, 3 or 4 years ago it would be normal to see up to 40 siskins in the garden around late January/early February,last year they were far and few between & this year I have not seen one.
I have five or six aviary bred pairs that will call them in when they hear them flying over but they are just not here this year.
I put it down to weather patterns,