The Sea of Cortez cradles an incredible exuberance of life. Cold upwelling water rich in nutrients and plentiful sunlight feed phytoplankton that is in turn grazed on by zooplankters. Bigger plankton feed on the smaller and are in turn consumed by fish that disappear down the throats of waiting birds. Soon the energy flow results in the production of eggs. The large white patch in the upper left of this photograph contains tens of thousands of elegant terns. The background noise is a cacophony of calls that blends together in an undecipherable high-pitched clattering of noise. The activity and energy expended seems beyond containment. Birds constantly boil up from the surface like some overheated cauldron of white feathers and orange bills. Over 200,000 pairs nest on this island of Isla Rasa. Over 260,000 pairs of Heerman's gulls and 17,000 pairs of royal terns nest here as well. If one thinks of a city with that many inhabitants the numbers become mind boggling.
On the right of this photo is a flock that shows an incredible exuberance for life. They have flown in from all over the United States placing a high priority on learning about what wild ecosystems can produce. Today we were lucky enough to have Dr. Enriquetta Velarde give us an introduction to Isla Rasa and tell us of her fascinating research and how closely tied nesting success is to El Nino. This bright and dedicated woman has been spending 3-4 months every spring on this island for the last 22 years. Later she led us through thousand of Heerman's gull nests to the overlook in this photo. These terns have been flying about the island in massive flocks before finally settling in about a week ago to start nesting. Their social tolerance for each other is remarkable. They are packed in like their prey in a can. It almost appears that they are touching each other. Many of us later felt we had observed not scenes but a spectacle.
After a barbecue lunch on deck we cruised on to Isla San Estaban for afternoon hikes. This island was used by Seri Indians and still has roasting pits they used for cooking agaves. Our guests enjoyed an energetic walk to the agave pits and to explore the central valley of this remote island. One of the naturalists found a pinto chuckwalla. These are large endemic lizards reach over four pounds and have an interesting orange and gray blotched skin. We took Zodiacs back to the ship, as beautiful sunset colors faded from the western skies.
