Boa constrictor is a large, heavy-bodied species of nocturnal snake. It habits in North, Central, and South America, and in some islands in the Caribbean. All subspecies are called "Boa constrictors", but people usually refer with that name to the red-tailed boa (BCC). Boas constrictors can length up to 4 metres (females are bigger than males) and weight around 27kg. It can detect heat with it lips, and they cannot see very well during the cycle of skin changing (the substance that lubricates between the old and the new skin covers it eyes making them look opaque). They eat mammals and birds as well as amphibians. It haunting technique consists in a fast strike to grab the prey with it teeth and then constricting it to death.