Baby Whales are Something to Celebrate
Tara A. Spears
Recent strong waves, westerly winds and high tides caused a strange occurrence along the Jaltemba Bay beach. Three different whale placentas washed up on shore creating quite a stir. After two stressful years surviving the pandemic by practicing stay at home, most visitors are so excited to be able to travel to Mexico and have something positive to celebrate! How marvelous to know that the environmental conditions are healthy and right for the delicate ocean life along our slice of paradise. While many of the adult whales that came to our area to breed are already heading north on their return migration, the mothers with nursing calves are still here. Calves are born during migration in the shallow lagoons and bays of coastal Mexico from early January to mid-February. From mid-February to May, eastern North Pacific gray whales can be seen migrating northward along the U.S. West Coast. It’s a great time to take a whale watch tour.
There are several local professional captains that provide boat rides to see the whales and who respect the giant mammals by following the whale watching regulations. The whale watching industry in the area is based around humpback whales migrating to the region each winter. According to Sayulito biologist, Nico Ransome, other animals that cruise the coast are: Bryde’s whales, gray whales, false killer whales, bottlenose dolphin, pan-tropical spotted dolphins and rough-toothed Dolphins
. There are 39 species of cetaceans recorded in the Mexican Pacific, which is over 40% of species recognized worldwide! From a boat you might also see turtles-usually the olive ridley; manta rays and a great diversity of bird life around the JB islands.
It’s so amazing that this part of the Eastern Pacific Ocean is part of several whale species migration routes. One whale that you will find in JB is the gray whale, which are known for their curiosity toward boats. Gray whales make one of the longest annual migrations of any mammal, traveling about 10,000 miles round-trip and in some cases upwards of 14,000 miles. On their migration routes they face threats from vessel strikes, entanglement in fishing gear, and other sources of disturbance.
During the 6-7 months that whales are on their wintering grounds, they primarily fast, breaking down stored fat for energy. They can lose 16-30% of their body mass during this time before returning to the summer feeding grounds. Whale gestation is 11-12 months. Migration and reproduction are connected, since it’s best for the mothers to reach warm waters before giving birth. Gray whales have a special adaptation called delayed implantation; the embryo does not start developing in the mother’s body until a few months after she becomes pregnant.
Several Interesting gray whale characteristics: Baby gray whales gain 190 lbs. per day while nursing in the lagoon. They don’t suckle but rather bump a slit on mom’s belly which stimulates a squirt of fat-rich milk. It’s the consistency of toothpaste, making it easy for the calf to swallow in the water.
Baby gray whales are born tail first and there is usually another female present who acts as a midwife. March and early April are good times for human-whale interaction, as mom and babies are ‘hanging out’. It’s thought playing with the humans on the boats is a diversion for the whales.
Another species that you might see in our area is the Humpback. Humpback whales are larger and darker colored. This whale sucks in krill through their baleen plates, which act like a sieve.
Humpback whales are a favorite of whale-watchers, as they can be found close to shore and often display activities near the surface, such as breaching (jumping out of the water) or slapping the surface with their pectoral fins and tail.
There is something so joyously elemental about seeing whales in their natural environment. And catching a glimpse of a mother with baby is certainly uplifting! Enjoy your boat ride, enjoy the scenery, and let your cares float away on the waves.
