Female killer whales reach sexual maturity when they grow to about 15-18 feet (4.6 m-5.4 m) long, depending on geographic region. The gestation period for killer whales varies from 15-18 months. Birth may take place in any month--there is no distinct calving season. Calves are nursed for at least 1 year, and may be weaned between 1-2 years old. The birth rate for killer whales is not well understood, but, in some populations, is estimated as every 5 years for an average period of 25 years. Killer whales are highly social animals that occur primarily in relatively stable social groups that often range in size from 2 to 15 animals.
Other symptoms that alert you to a case of head lice include a ticklish feeling on your head, especially at night. The head louse is a nocturnal creature and is more active in the dark than during the light of day.
Head lice are tiny insects. They are about the size of a sesame seed (2â3 mm long). Their bodies are usually pale and gray, but color may vary. One lice is called a louse. Head lice feed on tiny amounts of blood from the scalp. They usually survive less than a day if not on a person's scalp. Lice lay and attach their eggs to hair close to the scalp. The eggs and their shell casings are called nits.