fearless

[burrealist]

thawed lake (This gives a good impression of ice without mentioning the ice, and it's only spoken in two words)

swallows new snow  (Hmm, I'm confused as to what the "new" word means-- I'm guessing a change of season, but in that case, the snow would be old and thawing itself. So I'll have to think about it, hard.)

robins lurk  (The sound of the word "lurk" reminds me of some dark, murky, moist void. I like the use of the word. I'm guessing robins suggest a seasonal change, even though I wouldn't know. The thawing lake suggests it to.)

So, I'm left with not enough information about the Robins, like everyone else has said. One more word, maybe? You gave a very serene image to us, so thank you. I also like that you didn't constrain yourself to a syllabic count. The little poem seems to be free of constraints, like the seasonal change into Spring. Maybe the final word you use could be open-ended, instead of harsh and cut with "lurk".