The whales migrate to the islands to give birth to their babies (calves) and stay in the area for up to 4 months, giving the babies a chance to get some size before they migrate to Alaska. Here is a mom and baby. If you look close, the spray is coming from the babies blow hole.
There isn't really any food for the whales in this area so the adults are basically fasting the whole time they are in the islands. They don't eat until they get further north. The babies however, nurse up to 100 gallons of milk a day from their moms. The milk is the consistency of cottage cheese or thick yogurt.
They have never recorded or seen a live birth of a humpback whale in the ocean, which seems unbelievable. They think that the moms calve on the east side of the island but they are not sure. You can tell approximately how old the baby is by how frequently is comes up for air.
Of course each day ends with an incredible sunset. You will see people lined up everywhere, just taking it all in, both tourists and locals. It is magical and a great time to reflect on all the gifts of the day and to give thanks for being in such a beautiful place.