Do you fly at night sometimes? I flew in my dreams last night with arms outstretched for gliding over rooftops. I didn’t see any birds although on landing back in reality in the morning I learned that an estimated 10,400 birds had flown across James City county overnight. They headed ESE at an average speed of 14 mph.
The fall migration begins in August for some birds, including green herons, yellowthroat warblers, and the scarlet tanagers that were featured in last week’s post. Normally active by day, they migrate at night for safety. The numbers passing through surged between 10 and 11 pm, flying at 1,500 feet, although nocturnal migrants sometimes fly up to 10,000 feet to save more energy.
I checked other counties I know. Over 64,000 birds flew SSE down the Appalachian chain at around 3,000 feet across Pocahontas county, WV. If you live in the United States, you can check the spring and fall migrations in your country from radar records at The BirdCast Migration Dashboard.
Spotting a Scarlet Tanager in the upper story of an Eastern Forest transports me to the tropics. And it is a tropical forest dweller in our winter months.
Our Northern Cardinal is almost as rosy and House Finches a bit less. Their red plumage is thought to come from carotenoids obtained in the diet (originally beta-carotene, the abundant precursor in plants—think carrots). Since tanagers are mostly insectivorous and insects have a lot of carotenoids, there is an easy explanation for why tanagers are bright red, except for an awkward fact.
While cardinals remain much the same color the year round, male Scarlet Tanagers are much less rouge when they go south, although they still have black wings and a black tail. They look like female tanagers, olive-yellow. Their diet is still based on insects in the tropics, so that is unlikely to account for the change. Since their testosterone levels plummet to female levels after the breeding season, does that suppress gene expression in the liver where carotenoids are converted to pigments (by p450 cytochrome enzymes)? Please enlighten me, readers.
Ozone hole shrinking in the southern hemisphere (NASA, 2021)
Did you ever regret you hadn’t met someone after hearing it was too late? I did today. James Lovelock was one of my scientific heroes. He died on Tuesday at age 103.
I knew people who worked with him at the Medical Research Council in London in the late 1950s. His research on cryopreservation laid foundations for freezing tissues, sperm and human embryos for in vitro fertilization technology. I wrote about this contribution in the biography LET THERE BE LIFE (2019). With hindsight, I am sorry I didn’t reach out for his personal recollections when I interviewed other pioneers for the book. Perhaps I felt too timid to approach a saint.
He didn’t receive universal acclaim for his theories and projections for the global climate. But I admired his courage to be an outsider and able to admit a mistake. Taken as a whole, his works have had immense impacts for science and society.
After prestigious institutions in Britain and the USA, he set up a private laboratory for independent research in a barn close to the county line between Cornwall and Devon. It was a fitting place for a man who began life in a humble home and as a Quaker when careers in British science were hard to pursue without a privileged background for attending university.
He was as much an inventor as a scientist. After pioneering cell freezing in London, he turned to atmospheric research and, then, to environmental science. His electron capture detector became the go-to technology for monitoring atmospheric pollutants, such as chlorofluorocarbons (from refrigerants). CFCs were ‘eating’ the atmospheric ozone layer that shields life from ultra-violet light. Detection of the ozone hole earned Nobel Prizes for two chemists. The Montreal Protocol of 1987 that banned CFCs is a model for global environmental policy.
Lovelock became widely known for the Gaia hypothesis (named after the Greek god for Mother Earth). He regarded the Earth’s atmosphere as a self-regulating whole that maintains homeostasis by feedback between the atmosphere, oceans and life forms, by analogy with physiology. Critics asked how such a state could have evolved through natural selection of countless species (the major forces being phytoplankton, grasses and trees). Nevertheless, the idea is influential and embraced by environmental activists.
Although he declared himself a ‘Green’, he was too much his own man to mind standing outside the mainstream. He ridiculed renewable energy sources now heavily invested by governments and advocated nuclear energy instead. Time will tell which is the better policy, if not already too late for a tipping point in global warming. He persuaded me that the time for sustainable development (i.e., ‘growth’) is past and human society needs to concentrate on resilience and preserving biodiversity.
James Lovelock deserves a seat in the pantheon of environmental guardians.
We released Lilah today, sending her along the path ahead of us. “You can run to the end and wait for us there!” The path feels empty without our companion, her coat shining white and golden and tail wagging to share joy and unconditional love.
The epitaph on the tomb of Lord Byron’s dog, Boatswain, captures a tribute I wish I had written of her.
‘Near this Spot are deposited the Remains of one who possessed Beauty without Vanity, Strength without Insolence, Courage without Ferocity, and all the virtues of Man without his Vices. This praise, which would be unmeaning Flattery if inscribed over human Ashes, is but a just tribute to the Memory of Boatswain, a Dog who was born in Newfoundland May 1803 and died at Newstead November 18th 1808.’
These bluebirds are residents here all year. The first was abandoned but we now have eggs and chicks in two nest boxes. After cool weather, it is now warmer and insects have hatched for parent birds to stuff in the wide beaks of demanding youngsters. They often fly to the ground from a perch for a morsel invisible to us. From a distance, the male plumage looks slate-blue but close-up in the sun they are gorgeous blue and rouge. Evidently, the blue color is created by light scattering (like a prism) whereas pigment is responsible for their sky blue eggshells. Why they are blue to match plumage when many other cavity nesters have white eggs with or without speckles is a question I can’t answer. Recent research confirms that birds tend to be more colorful in the tropics, but our bluebirds are among many exceptions to the rule.
Roger musing about Peace with Nature 