Sorry that you have lost some. How are they being kept, and what type of waterers are they using? Weather in February is usually very cold for shipping chicks, especially if they are in the mail more than a day. I have noted in past years, that many chicks have feeders filled with pine shavings and nipple waterers in some feed stores I have visited. They don’t seem to keep things cleaned out. Bantam chicks cannot reach some of the nipples. You see chicks with pasty butt, and no one seems to care if you point that out. I usually try to get chicks in milder weather months, and try to get there the day they arrive. The stores that keep the chicks away from people handling them are preferred as well.