The gray whales have been here in San Ignacio Lagoon for two weeks already—and it’s only early January!
We were so excited to have the season’s first gray whale sighting in the lagoon 2 weeks ago. I was up in San Diego a month ago, and a local whale watching company told me that their first sightings of the gray whale migration this season were a week earlier than normal. So, fingers crossed and cheers to a great season!!
The gray whales make a major annual migration with a 10,000-mile round-trip from the Bering Sea to San Ignacio Lagoon. Food sources along Baja are almost non-existent for the gray whales, so why the heck do they stress themselves to fast and make this heavy-duty trip?
It must be especially difficult for new mamas to lactate while fasting for many months at a time, while their newborn calves grow from 12 – 14 feet up to 20 feet or longer, putting on 60 – 80 lbs of weight a day. All of that growth is supported by calves feeding on a mother who is unable to feed herself… Interestingly, research monitoring body size and blubber thickness indicates that fully-grown females are able to support extended lactation fairly easily. It must be a lot more challenging for younger females. Females become sexually reproductive at 10 years old, but don’t reach full size and have ample blubber for another 30 years!! A fully mature female gray whale is usually twice the size of a first-time mother.
Why Do Gray Whales Migrate Vast Distances?
Why make this long swim every 2 years to give birth in a lagoon 5,000 miles away? We are doubtful it’s because of the high salinity of the lagoon, although that is an often quoted reason. It’s not because of the relatively warm water of the lagoon or energy conservation either. That’s because a healthy calf is well insulated for water 20 degrees colder than San Ignacio!
There has to be more direct and high value to the whales to make this migration worth the extremely long swim. I think it’s because San Ignacio Lagoon is a safe place for the newborn calves to learn the basics of life. Here, whale mothers help their calves grow strong, protected from predators, so they can prepare for the long return journey north.
Calf Haven: Why is the lagoon safe for calves?
I think it comes down to orcas (killer whales), the nemesis of gray whale calves. As we heartbreakingly see in Monterey Bay, California, orcas prey on gray whale calves. And yet there are no reports of orcas ever entering the lagoon. Why??? No orca has ever been sighted inside the lagoon. If a gray whale can navigate the sandbars at the entrance to San Ignacio, surely an orca could? The thing is that orcas navigate and hunt their prey using echolocation, which wouldn’t work very well in the shallow and muddy lagoon. The killer whale would be going in mostly blind and feeling their way around, which would leave them vulnerable to beaching and to full-size adult gray whales.
As we saw with gray whales attacking and killing whalers in the 19th century, these are big, powerful animals with a temper. “One fluke slap from a big gray whale across the face could easily put the killer whale out of action permanently. For gray whales, coming to the lagoon may be an evolved behaviour to avoid predation at the most sensitive time in their life cycle, during mating and with very young calves”. – Eye of the Whale: Epic Passage From Baja To Siberia by Dick Russell.
Point of interest with regard to San Diego gray whale migration watching. San Diego Bay was a birthing lagoon in the 19th century. Historical records recount stories of ladies being taken out for a row around the bay only to be covered in interesting-smelling whale blows. Those whales were wiped out by whalers, and none have ever returned to give birth there. Sad but true. Thankfully, we get to see loads of gray whales in San Ignacio Lagoon.
Hope you can join us.
- Captain Mike, Baja Expeditions.
Find out more about the best eco-friendly, multi-day whale watching in Mexico: “Whale Watching in Baja California: Up Close with Giants”
Baja Expeditions has been Baja’s pioneering eco-expedition company for almost 50 years and counting. 2021 will be the company’s 29th season at San Ignacio Lagoon.
Author Mike Lever is the company President. He and his team have breathed new life, energy, capital, and previously unheard levels of luxury into Baja Expeditions.
