Magdalena Bay and Hull Canal, Baja California Sur

Magnificent marine mammals have dominated our first few days in Baja California. And so they should. But today was a day for reflecting on another form of vertebrate - the birds. We have come here to explore the ocean and desert and to learn about the living and non-living parts of Baja's complex ecosystems. We are visitors, but so too are many other animals. Humpback, blue and gray whales have come from afar. The rich, warm waters are what they seek for breeding and giving birth to their young. Similarly, many bird species have no choice but to escape winter's ice and snow, so they head south for the warmth of the near-tropics. We found some of these "neotropic migrants" yesterday as we walked near Cabo San Lucas, including northern cardinals, western tanagers and least and spotted sandpipers. Today we encountered thousands more - mostly the large shorebirds that have flown here from the Great Plains and Arctic tundra to enjoy the winter season and fatten up on intertidal invertebrates and small fish. Hull Canal, a long, narrow passage separating picturesque Isla Magdalena from mainland Baja, is a paradise for wading birds. Marbled godwits, long-billed curlews, willets, whimbrels, black-bellied plovers and western sandpipers challenged us to identify them from our ship's bow. Great blue and green herons, great, snowy, and reddish egrets, and white ibises waded in the shallows or rested on the protective mangroves. Three cormorant species - double-crested, brandt's and neotropic - flew in long lines or dove under the murky surface in search of schooling fish. Terns and pelicans plunged from on high to capture their prey.

In preparation for the day, Bryan was pleased to present a slide program on the ecology of seabirds and their adaptations to a windy, wet, salty and unforgiving environment. Light wing-loading, a salt processing gland and the ability to take advantage of the Earth's winds are among their secrets to success.

Even with birds surrounding us, our 8th species of marine mammal appeared - the California Gray Whale. As Sea Lion wound its way north in Hull Canal, mother grays with new calves began to appear. Like the shorebirds, they seek these warm, protected waters. The "tiny" calves need warmth as they nurse voraciously, adding 40 or more pounds per day, and gaining strength in preparation for a long and hazardous journey north, perhaps to the Bering Sea. That adventure may begin as soon as next month. And, like the whales, many of the birds will soon head north again. A healthy layer of fat - gained from their invertebrate food - will provide them with the energy they need.

And then there are those other migrants - ourselves. All too soon we will have to move northward again. But for now, there are whales to meet and a 60-mile long sandbox in which to play. We can keep jumping, and won't think about migrating yet.