In Baja, marine mammal expert Lorenzo Rojas explains that the fishermen, who must limit their activities during the whale season, “understand well” that tourism income to the community from whale watching can equal or surpass that generated by fishing. “They have adopted the gray whale as a symbol of their culture and their community,” Rojas says.

Ecologist Steven Swartz takes the view that gray whale conservation is a unique platform for studying the macro phenomena affecting the whales’ health and behavior. Recent observations of emaciated adults and calves, for example, suggest negative effects caused by climate change in the gray whales’ northern feeding grounds. As with the monarch butterfly migration, there is a warning here as well. “To me,” Swartz says, “gray whales are sort of sentinels from the sea.”

The Urge to Travel
Animal migration is a mystery yet to be unlocked. Wildebeests, whooping cranes, some sharks, many insects, songbirds, even a strain of the humble slime mold are repeatedly driven to travel at some phase of their life cycle.

Migration is an adaptive trait, hardwired into a species’ DNA and vital to its survival. The origins of migration seem basic enough: mass movement in response to seasonal fluctuations in climate and food supply or to population pressure. But understanding the actual mechanisms of the behavior is tricky. Scientists have examined the sensory apparatus that allows a population to detect en masse the moment of equinox for beginning a long trek (as monarch butterflies do) or to process complex navigational problems using landmarks, moon phases, odor, magnetic fields and celestial clues. One bird, the indigo bunting (right), uses a single star, Betelgeuse, as a reference point. Much more remains to be learned.

Note: This article was originally printed with the title, "The Behemoth and the Butterfly".

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