When it’s cold up north and the “snow bird” tourists start to arrive in Ixtapa Zihuatanejo, it means that the whales are not far behind. Humpback whales are famous for their long complex songs and for their acrobatic displays; breaching, jumping and spy-hoping, delighting all who have the good fortune to observe them. They are known as Humpbacks (Megaptera novaeangliae), from the shape of their backs when they dive.
During the northern winter and early spring, many Humpbacks play off the coast of the Ixtapa Zihuatanejo area. They are part of a large stock of whales that travel between Northern California, Oregon and Washington states coming south each season. They are thought to number around 1,250 individuals. And just like “snow birds,” more come south each year. This stock is generally considered to be growing.
Like many other local winter visitors, Humpbacks are social creatures. They travel in pods, large loose social groups that vary widely from week to week. Only mothers and calves stick close together for the winter season. Humpbacks sometimes hunt cooperatively too; rounding up massive amounts of prey in a technique called “bubble net feeding”. The hunting members of a pod form a large circle and then blow a wall of bubbles as they swim to the surface in a spiral path. The cylindrical wall of bubbles makes the trapped prey swim to the surface, where the whales eat them.
Humpbacks are seasonal feeders; which means that they are not usually eating while they stay in the warm waters off the Guerrero coast. They are baleen whales or filter feeders that eat tiny crustaceans, krill, plankton, and small fish, consuming up to 5,500 pounds a day in two feedings! They make the most of their summer by feeding heavily in the rich waters of the northern coasts and actually take a vacation from hunting and feeding when they come south.
Humpbacks come in a variety of color themes, ranging from black to grey to white to mottled and have distinctive markings on their tails and flukes, one of the way scientists who study the various groups (stocks) can identify individuals. Adult Humpbacks weigh as much as 6,000 to 15,000 pounds and the females out weigh the males. They swim by moving their tails up and down (fish swim by moving theirs from side to side) and swim about 3 to 5 miles an hour unless they are in danger – then they can burst into speed up to 15 miles an hour. When you are watching these beautiful winter visitors, you can often see them playing close to shore and then, in the blink of an eye, they are off and gone. Perhaps a friend has sent out a song to join up, or perhaps they are just ready to move on.
You can look for Humpbacks by taking a boat tour out of Barra de Potosi or Zihuatanejo, or often see their spouts from local beaches. Keep on the lookout and you will be rewarded with sightings!
For more information about the Ixtapa Zihuatanejo area, see: