Bedbugs can live undetected for long periods of time hidden in mattresses and suitcases. Bedbugs are generally active only at dawn, with a peak feeding period about an hour before sunrise. They may attempt to feed at other times, however, given the opportunity, and have been observed to feed at any time of the day. Attracted by warmth and the presence of carbon dioxide (from humans), the bug pierces the skin of its host with two hollow tubes.