Rising Tide Images
Departing Kōlea
A male kōlea in his dapper breeding plumage, often referred to as a tuxedo, before the long flight from the tropics to the nesting grounds on the Alaskan tundra. In a few days, he will sense that the time has arrived to congregate with other previously solitary kōlea and depart collectively. The trip spans 3,000 miles of open ocean requiring a rigorous, energy intensive effort of 3 to 4 days and nights of nonstop flight at elevation ranging from 3,000 to 16,000 feet. Superb navigators with territorial fidelity, kōlea, or Pacific golden plovers, use the stars and the earth’s magnetic field to find their way over the featureless ocean to the same small patch of territory every year. They may use the earth’s magnetic field visually with the magnetoreception molecules of cryptochrome in their retina.
The physiological changes in migrating shorebirds, like this male kōlea, are astonishing. The necessity of increasing fat load for the sustained energy demands of long-distance migration has been compared to, in terms of percentage body fat, larding up to morbid obesity in humans. The surge in heart and lung capacity and increase in pectoral flight muscle are driven by hormonal changes (without the drudgery of exercise!).
Departing Kōlea
A male kōlea in his dapper breeding plumage, often referred to as a tuxedo, before the long flight from the tropics to the nesting grounds on the Alaskan tundra. In a few days, he will sense that the time has arrived to congregate with other previously solitary kōlea and depart collectively. The trip spans 3,000 miles of open ocean requiring a rigorous, energy intensive effort of 3 to 4 days and nights of nonstop flight at elevation ranging from 3,000 to 16,000 feet. Superb navigators with territorial fidelity, kōlea, or Pacific golden plovers, use the stars and the earth’s magnetic field to find their way over the featureless ocean to the same small patch of territory every year. They may use the earth’s magnetic field visually with the magnetoreception molecules of cryptochrome in their retina.
The physiological changes in migrating shorebirds, like this male kōlea, are astonishing. The necessity of increasing fat load for the sustained energy demands of long-distance migration has been compared to, in terms of percentage body fat, larding up to morbid obesity in humans. The surge in heart and lung capacity and increase in pectoral flight muscle are driven by hormonal changes (without the drudgery of exercise!).