Looking for Whales

Jacques Cousteau called the Sea of Cortés the “the aquarium of the world” (link), and you know it has to be a helluva big tank to hold 6,000 animal species – 4,854 invertebrates, 891 fishes, 181 birds, 36 mammals and seven reptiles (Brusca et al. 2005). We could discuss the “health” of the Sea of Cortés – the lack of freshwater flow and nutrients from the Colorado River; habitat destruction and bycatch by commercial shrimping; overfishing of sharks and groupers; over-harvesting of pearl oysters, sea turtles and whales; population crashes of the totuava (link) and vaquita (the world’s smallest and most endangered cetacean) and more (link, link). Maybe when I feel sufficiently misanthropic about the future of the “world’s aquarium,” I’ll depress you with some of those stories. For now I’d like to celebrate the remaining diversity in a diminishing sea.

Ron photographing humpback whale (Isla Danzante on the right)

Let’s begin with the biggest of the big – the whales. The Sea of Cortés is home to 18 species of whales, including blues, humpbacks, fins, orcas and greys (link).  I’ve seen gray whales from a panga in Ojo de Liebre (Scammon’s Lagoon) on the Pacific Coast of Baja. I’ve seen humpback, gray and pilot whales working and recreating on boats in the Southern California Bight. I’ve seen pods of orcas in Puget Sound and belugas in Alaska. But I had not seen a blue whale – the biggest of the bigs (up to 100 ft long) – until now.

Launching a panga at Ensenada Blanca

I attended a presentation on blue whales at Eco-Alianza de Loreto, a non-profit conservation group (link). Dr. Diane Gendron, research project director for CICIMAR (Centro Interdisciplinario de Ciencias Marinas) in La Paz, talked about blue whale life history and the research her group was doing in the Sea of Cortés. At the presentation, I met Martin Romero, a whale-watching guide working out of Ensenada Blanca. He looked like a middle-aged fisherman: medium height, strongly built, black wavy hair and sun-weathered skin. He spoke in English and Spanish describing his operation: a 25-foot, fiberglass panga with a canvas sun shade that carries six passengers; $300 USD for a half-day. Martin had been a guide on whale-watching boats operating out of La Paz for more than a decade before he went out on his own. He moved to Ensenada Blanca, started a company (“Super Pangas”) and was certified by Parque Nacional Bahía Loreto to operate in the park. He gave me his cell phone number (011-613-104-2254) and I told him I’d call when I had six people.

Humpback whale breaching in Bahía Danzante (click to enlarge)

We rounded up three people from the Spanish classes Rande and I were taking from a local teacher. Ron, who was in my Spanish class, would bring his fishing buddy. Rande called Martin (she speaks better Spanish than I do), discussed the weather forecast and made plans for us to meet in a couple days. Martin lives in a compound of several small, concrete-block houses near the fishing camp in Ensenada Blanca. We met him at his house and followed him to the cove where the fishermen launch their pangas (and where I launch my kayak). He waded out to a panga anchored in shallow water, pulled it onto the beach and we climbed in over the gunwale. He had water and life jackets for everyone. Coming out of the cove, Martin gunned the motor and turned the boat toward the south end of Isla Danzante. We had only covered a couple miles when we spotted a humpback whale between Danzante and the mainland. The whale breached. We saw another humpback closer to shore. It was a female with “una cría de ballena” (a baby whale). Martin said that baby animals are called crías (bebé is a human baby). We followed them for about 10 minutes when Martin said it was time run offshore to find blue whales.

Humpback whale with cría de ballena (baby whale) in Bahía Danzante

Humpback whales occur worldwide and are considered by the U.S. as endangered and depleted throughout their range. There may be 20,000 individuals in the Eastern North Pacific. They feed in the Gulf of Alaska during the summer and migrate to tropical waters of Hawaii (approximately 10,000), Mexico (6,000-7000) and Costa Rica (1,000) in the winter (link). They grow to 60 feet (females are larger than males), weigh 25-40 tons and live about 50 years (link). About 2,000 humpback whales frequent the Sea of Cortés and some individuals spend the entire year there (link).

Spinetail mobula jumping near Isla Danzante

Between islas Danzante and Carmen we saw several spinetail mobulas (Mobulidae, same family as giant mantas) jumping out of the water. Adults have a wingspan of 5-8 feet (Humann and Deloach 2004); the ones we saw were about 3-4 feet across, probably juveniles. It’s pretty amazing to see them jump 2-3 body lengths out of the water, sail through the air and crash back into the sea. Why do they expend so much energy? The usual reasons given for why fish jump include: avoiding predators, ridding themselves of external parasites and free-riders like remoras, communicating among themselves (males could be advertising their fitness to potential mates) and maybe just for fun (link). Jumping mobulas are often in groups, and they’re pretty large, so they’re probably not jumping to avoid predators. Beyond that, we’re just speculating.

Spinetail mobula jumping

Martin said the blue whales were feeding in deep water south of Isla del Carmen. Once we were south of Carmen, Martin cut the throttle to half speed. I asked him how deep the water was beneath the boat – “Quinientos metros más o menos ” (500 meters or 1,600 feet). Blue whales feed on euphausiids, pelagic shrimp-like crustaceans commonly known as krill. They’re less than an inch long and occur in large aggregations in the Sea of Cortés hundreds of meters below the surface (link). Blue whales feed by engulfing tons of water in their mouths and use their tongue to force the water out through baleen plates, which are made of keratin and act like a sieve to retain the krill.

Blue whale spouting (Sierra de La Gigante in the background)

Everyone was scanning the horizon for spouts, columns of moisture-laden air forcefully exhaled while the whales were on the surface between dives. Martin saw a blow in the distance; his trained eyes picked it up before the rest of us. He turned the boat, but did not change speed. No need to rush and scare or stress the animal. The whales spend several minutes on the surface between dives. We were near the whale when we saw its tail flukes. Martin said it wouldn't return to the surface for 15-20 minutes, so we continued motoring looking for another whale.

Blue whale diving (Isla del Carmen in the background)

In all, we saw a half dozen blue whales. We were about 20 miles offshore between islas Carmen and Montserrat and the only boat on the Sea of Cortés for as far as we could see. Skippers of whale-watching boats often share information among themselves over their marine radios, but there was no one else around to help us find whales. I was a bit skeptical about finding whales in such a big area, but Martin knew where they would be and how to find them. They’re big (3-4 times the length and wider than our panga), but hard to spot when you’re only a few feet above the water.

Blue whale diving

Blue whales occur worldwide and are considered by the U.S. as endangered and depleted throughout their range. They grow to about 100 feet (females are larger than males) and weigh up to 165 tons. Lifespan is unknown, but they mature between 5-15 years (link). In the In the Eastern North Pacific, blue whales spend the summer and fall from the Gulf of Alaska to the U.S.; they migrate south to winter-spring grounds to high productivity areas off Baja California, in the Sea of Cortés and in the oceanic region known as the Costa Rica Dome. The best population estimate is about 1,600 individuals (link). Between November and May, approximately 300 blue whales enter the Sea of Cortés to feed, reproduce and nurse their calves, primarily between Loreto and La Paz (from Dr. Gendron’s presentation).

Blue whale diving near Isla del Carmen

Researchers from CICIMAR have been monitoring blue whales in the Sea of Cortés using photo identification for two decades (the mottled pattern on their blue-gray skin is distinctive enough to recognize individuals). They have over 600 individuals in their photographic catalogue and have skin samples from over 300 individuals (from which they can determine the sex). The oldest individual was first photographed in the 1980s. Females have a calf every two to three years. Several individuals have repeatedly returned to areas within the park (from Dr. Gendron’s presentation).

Bottlenose dolphin approaching the panga in Bahía Danzante

Crossing Bahía Danzante on the way back, we were joined by a pod of bottlenose dolphins. Pangas don’t displace a lot of water, so the bow wave is not very big. Still, several of the dolphins swam beneath the bow zig-zagging back and forth looking for the best ride. A female with her cría swam over to the panga; she stayed between the boat and her baby, but brought it right up to our bow like she was showing it how to ride the bow wave. The pair moved off to our starboard and surfaced to breathe. Somehow the baby ended up between the female and the panga and swam back toward us. When it got close to the panga, another adult came from our port side and positioned itself directly below our bow. The mother and the second adult guided the baby away from the panga, where they swam for another minute before the pod left us and headed north.

Female bottlenose dolphin with her baby approaching the panga

Baby bottlenose dolphin surfacing to breath

Bottlenose dolphins occur around the world in inshore to offshore waters at tropical and temperate latitudes. Population estimates range from about 3,000 in the Eastern Tropical Pacific to 2,000 off California-Oregon-Washington (link). They grow to 6-12 feet, weigh 300-1,400 pounds and live 40-50 years (they mature at 5-14 years) (link).

Snorkelers in Bahía Danzante

On our way back to Ensenada Blanca, we passed a couple snorkeling in the shallow water near Villa Del Palmar, a timeshare resort. We all agreed that it was an incredible day.

Postscript: Mexico has responsible whale-watching guidelines and these activities can only be conducted with permits issued by SEMARNAT (Secretaría de Medio Ambiente y Recursos Naturales) (link), the Secretariat of the Environment and Natural Resources. Thirty species of marine mammals have been recorded in Parque Nacional Bahía Loreto, which is 75% of all the species recorded in Mexican waters (link).

R. Brusca, et al. 2005. Biodiversity, ecosystems, and conservation in northern Mexico. J.E. Cartron, G. Ceballos, R.S. Felger (editors). Oxford University Press, pp.179-203.

P. Humann and N. Deloach. 2004. Reef Fish Identification: Baja to Panama. New World Publications, Jacksonville, Florida. 343 pp. + appendices.