This winter for the first time I seriously looked into arthropods found on snow, from multiple walks in the middle of the winter my most successful days were when it was -2C, but since February I struggle to find any, I come out in warmer weather, 0C, +2C, +4C (as today), but find a whole zero invertebrate life in the forest, what could be the reason for this? Did all insects died in periods of freezing? What is your experience in that field?
Temperature swings might have something to do with it. I find the best conditions are a mild evening for temperatures accompanied by newly fallen snow, then clearing the next day with mild weather continuing.
My best day so far followed an entire week when the overnight lows ranged between -11C and -18C, and every day was windy and/or cloudy. But then on March 1, there was an accumulation of 1cm of fresh snow from the previous evening which stopped by the morning, and it climbed up to -2C or warmer that day with very little wind, and no cloud cover. I imagine all of these factors combined led to the explosion of life I encountered that day: tons of chironomids climbing up from the margin of the lake and then crossing the trail to continue to the hill on the other side, and an assortment of spiders, Boreus, stoneflies, and springtails besides. I even found my first Chionea in a few years! I had especially wanted to find one before I set out, but never imagined I’d have that wish granted!
I wonder now if the extended period of unfavorable conditions that preceded that one good day precipitated the change when the poor weather finally broke.
I experienced the similar situation around January, but last 1,5 months it’s all been empty.