As I watch waves of migrant birds move through our valley, beginning in mid-July with rufous hummingbirds and a few early shorebirds, followed by raptors pouring over the Wellsvilles mountains in mid-August, then September when many of our songbirds head for the tropics, and lastly in November come the waterfowl- ducks, geese, and swans stream through by the thousands, I am thunderstruck. The remarkable physiology that allows our avifauna to find their way through storm and unimaginable distances to their destinations defies logic. Fraught with peril, it is the most dangerous part of their existence since leaving the nest.
In the past two decades, our understanding of the navigational and physiological feats that enable birds to cross-immense oceans, fly above the highest mountains, or remain in unbroken flight for months has exploded. What has been learned of these migrations is nothing short of extraordinary.
Bird migration entails almost unfathomable endurance, like a sparrow sized sandpiper that flies nonstop from Canada to Venezuela- the equivalent of running 126 consecutive marathons without food, water, or rest- avoiding dehydration by drinking moisture from its own muscles and organs, while orienting itself using the earth’s magnetic field through a form of quantum entanglement that made Einstein queasy.
Crossing the Pacific Ocean in nine days of nonstop flight, as some birds do, leaves little time for sleep, but migrants can put half their brains to sleep for a few seconds at a time, alternating sides- and their reaction time actually improves.
Birds add muscle when and where it’s needed, and shrink it away when the task is completed. Barred godwits lose their entire digestive system for flight. They burn fuel with extraordinary efficiency, qualities that would make endocrinologists, bodybuilders and weight loss gurus salivate. Birds can pack on fat without obesity’s downsides, add muscle when and where it’s needed, and burn fuel with extraordinary efficiency. Most of their fuel comes from omega 3 fatty acids gained by eating certain crustaceans and other invertebrates along the way. These fats also provide water and assist with protein digestion and synthesis.
Birds have intricate air sacs connected to their lungs allowing 90% efficiency in capturing oxygen, far beyond the human respiratory system capability. This is combined with super-efficient hemoglobin molecules. Pulmonary embolism, which I recently experienced, is unknown in migratory birds. Might these remarkable beings have something to tell myself and medical science?
Regarding navigation, in addition to sight and smell, it has been recently discovered that when a photon of blue light strikes cryptochrome in the bird’s eyes it becomes magnetized through quantum entanglement allowing them to see the earth’s magnetic lines. That’s amazing! Much of this information is from “A World on the Wing: The Global Odyssey of Migratory Birds'' by Scott Weidensaul, a beautifully written book you must read.
Jack Greene for Bridgerland Audubon Society and I’m wild about Utah.
Sound credit to Kevin Colver.
