The beach

See how the water breaks into white caps in the wind? Sleek black shags—Pelagic Cormorants and Double-crested Cormorants—are strong swimmers that plunge into the pelagic waters in search of small fish. Grebes and Loons are also busy in healthy parts of the Bay. Brown Pelicans wheel overhead, and terns and gulls of several species are common. Smell the air. It is crisp and clean with the unmistakable, dark fragrance of the bay. What you smell is geosmin, a potpourri of sesquiterpenoids, a cocktail of gasses produced by blue-green algae, filamentous bacteria, and other prokaryotes. You may associate geosmin with the smell of a rainstorm, a lake, or the ocean. It’s a smell that reaches to something deep inside us, and hopefully you find it as comforting and familiar as it is primordial. Your olfactory system can detect geosmin in the air at less than 10 parts per trillion (Polak). There are few other fragrances to which we humans are so attuned. Some evolutionary biologists suggest that the capacity to detect this scent may say something of the important connection between water and its support of all life on earth, or as an ancient mechanism to allow us to find water sources. As you can see, this little beach teams with all forms of life, from the birds and barnacles to the little purple crabs that seem to fear their own shadows.