Like behavior best exemplified by salmon, which combine conventional open-water navigation and a keen sense of smell to find their way, today my spawn return home after migrating to each coast, to bask in the knowledge of others. They return to feed from the same tributary in which they hatched.
How my spawn return to the correct shoreline region is not completely understood. It appears they use some form of “map and compass” navigation based on information about position and direction of travel. This information most likely comes from a suite of environmental cues, including day length, the sun’s position and the polarization of light that results from its angle in the sky, the earth’s magnetic field, and temperature gradients, Uber, airplane, and the GPS on their phones.
Whatever the specific mechanism, as feeding time approaches, spawn have a seemingly inherited tendency to orient themselves toward the area from which they were discharged. By the time their planes land, they are guided largely by their sense of smell to the correct estuary.
Unfortunately their feeding time is brief. Mere days pass before they must use the same means to migrate back to school.
November 23, 2016