I saw this pretty little sparrow on the east side of the park, just a bit south of the gravel path that leads to the dog park. This area happened to be a verdant meadow three years ago. The mowers bypassed it, and the vegetation grew high as a human knee, and higher. That was perfect nesting habitat for Savannah Sparrows, as well as some other birds. They build their nests on the ground, and weave artful canopies and tunnels of grass to conceal them from overhead view. This bird may have been born in the Spring of 2019, when a thoughtful and empathetic park administration called off the mowing machines on this little patch of grass so that the bird parents could raise their babies. See “Saved from Mower,” Apr 26 2019. It’s a characteristic of these birds that they return to the place where they hatched. But what a shock. It has migrated here, flying by night for many miles, only to find that the home where it was born has been razed to the ground, devastated. To a bird raised in a verdant meadow, a mowed lawn is as good as a city bombed flat.
For two decades, the Savannah Sparrow has been the principal teacher of bird navigation skills to researchers willing to listen. Its orientation behavior during migration has been more extensively studied than that of any other bird species. The bird finds its way through “a system of interacting compass senses: magnetic, star, polarized light and, perhaps sun compasses.” (Source.) They are born with a migration map based on the earth’s magnetic field and on celestial rotation. Even birds raised in captivity that have never seen the sky can point in the direction of migration. They are able to correct their maps with experience, adjusting for changes in the earth’s magnetic field and for variations in polarized light. But what good is their “extremely flexible orientation system” if at the end of the journey, there is no home?