- Sexual maturity
After approximately 5 (females) or 7 years (males), and after they have reached a length of approximately 35-40 feet, females as well as males are considered to have reached sexual maturity. Females may mate every 1-3 years after reaching their sexual maturity, according to research. Males will head to breeding grounds to mate, compete, or if you are a young male humpback, just watch and learn.
- Gestation period
After a gestation period of approximately 12 months, female humpbacks give birth to a whopping baby, 10 – 20 feet in length and weighing 1 – 2 tons, depending on the size of the mother. Calves length is approximately the length of mom's head, so small moms, little calves, big moms, enormous young. The North Pacific calves are born in warmer waters around Hawaii, Baja California, and off the Bonin Islands of Japan. According to researchers calves are born positively buoyant, which means immediately after birth they will bob to the surface like a cork.
- Nursing
The mother nurses the calf for anywhere between 6 and 11 months. While feeding, mother and calf are close to the surface so that the calf can easily reach to breathe. The term nurse or suckle is actually not completely correct, since the milk is squirted by the mother into the mouth of her calf. The calf will 'latch' on to the nipple using the tip of the rostrum. Photos of new calves show the skin pigment worn away in the front. Also, according to researchers, the calves have no baleen in the very front of their mouths creating a small gap. If it were not this way, the milk would hit the baleen and the nutrition would be lost. Feeding the calves up to 100-130 gallons of milk, which is very thick, the consistency of yogurt, and 50% fat every day allows the baby to gain about 100 pounds every day. At this rate, researchers have discovered the calves rapidly grow 1 foot per month! Before its first birthday, the "little" humpback whale already eats krill and fish and has doubled in weight and length. The following year, if the mother returns to the breeding grounds, the yearling may follow, but not all do. Off the coast of Canada, many ‘little' ones have been seen and photographed staying and continuing to follow the food to small inland passages.
