Every week we hear from regular listeners and Minnesota school kids as they call or email us with their nature observations. This week, because of the Monday holiday, we only had two school reports. We did hear from a number of other listeners, tho. Topics in this week's talkbacks include invasive cattails, ravens, rabbits eating their own poop, the sound of the first "phoebe" song and a follow up on last week's discussion about sections of the Mississippi river becoming frozen. What are you