Off of Isla Carmen, the Gulf of California
Why is the Gulf of California (aka the Sea of Cortez) such a productive place to search for marine mammals? Complex bottom topography and ocean currents bring dissolved nutrients up from the depths to the surface, where light is also available in abundance. Light + Nutrients + Phytoplankton = Primary Productivity (the basis of all marine life). And where there is ocean productivity there will be consumers, from small to enormous, to make use of it. At least, that is the theory of it, and the theory was quickly put to the test.
Our first Baja California sunrise was savored from the fore deck of the Sea Bird just south of Isla Carmen, one of the largest of the islands of the Gulf, with morning sunlight reflecting off of the mountains of the Baja California Peninsula to the west. And so we began our search, watching the morning birds but ever scanning the distant waters hoping to spot a blow, the exhalation from a giant set of lungs that marks the presence of a great whale. We didn’t have long to wait. A blow was soon spotted off in the distance, its “bushy” shape identifying its maker as a humpbacked whale. Our morning was spent in the presence of … could we really be so fortunate? … a blue whale and, later, a fin whale. These are numbers one and two in size of all animals known to have ever lived, and we watched them both in the same morning! Both animals were swimming steadily, searching for concentration of prey to fuel their enormous appetites. Later we found ourselves in the middle of one such concentration, its presence marked by a group of common dolphins numbering in the high hundreds, or maybe there were a thousand of them for counting dolphins is a difficult proposition. The dolphins would disappear from the surface, descending to drive the “bait fish” to the surface, and then rise through the bait in a feeding frenzy. Hordes of plunge-diving pelicans and boobies likewise profited from the event, with Heermann’s gulls joining in to clean up the scraps from the bountiful table of the Gulf of California.
Why is the Gulf of California (aka the Sea of Cortez) such a productive place to search for marine mammals? Complex bottom topography and ocean currents bring dissolved nutrients up from the depths to the surface, where light is also available in abundance. Light + Nutrients + Phytoplankton = Primary Productivity (the basis of all marine life). And where there is ocean productivity there will be consumers, from small to enormous, to make use of it. At least, that is the theory of it, and the theory was quickly put to the test.
Our first Baja California sunrise was savored from the fore deck of the Sea Bird just south of Isla Carmen, one of the largest of the islands of the Gulf, with morning sunlight reflecting off of the mountains of the Baja California Peninsula to the west. And so we began our search, watching the morning birds but ever scanning the distant waters hoping to spot a blow, the exhalation from a giant set of lungs that marks the presence of a great whale. We didn’t have long to wait. A blow was soon spotted off in the distance, its “bushy” shape identifying its maker as a humpbacked whale. Our morning was spent in the presence of … could we really be so fortunate? … a blue whale and, later, a fin whale. These are numbers one and two in size of all animals known to have ever lived, and we watched them both in the same morning! Both animals were swimming steadily, searching for concentration of prey to fuel their enormous appetites. Later we found ourselves in the middle of one such concentration, its presence marked by a group of common dolphins numbering in the high hundreds, or maybe there were a thousand of them for counting dolphins is a difficult proposition. The dolphins would disappear from the surface, descending to drive the “bait fish” to the surface, and then rise through the bait in a feeding frenzy. Hordes of plunge-diving pelicans and boobies likewise profited from the event, with Heermann’s gulls joining in to clean up the scraps from the bountiful table of the Gulf of California.
