Farther along, Mission Blue intersected with Silverspot Drive. After I turned around on Callippe Court, I pondered the bittersweet experience of future generations who will be reminded of the iridescent butterflies that once flashed in the sunlight on San Bruno Mountain by the names on street signs. A century earlier, the bird had ranged across the Southeast, but unregulated hunting and habitat loss there and in Caribbean wintering grounds had decimated its numbers. Decades have passed since the last documented sighting, and in all likelihood, Bachman's warbler is extinct. Witnessing the last of anything is a privilege, but a sad one.
Memories are all that's left.
But memory can also be a beginning. For we remember what we related to. Science alone cannot assess the diminished quality of a world without the ivorybill or the Xerces blue. Psychologists have not begun to ponder the emotional toll of the loss of fellow life. Nor have theologians reckoned the spiritual impoverishment that extinction brings.