The clouds ultimately broke because of a life-changing course in terrestrial ecosystems with Tom Siccama and another in evolutionary biology with Charles Remington. “Five minutes after graduation, I got a job with The Nature Conservancy,” said Hoose, and he has worked there ever since. “That was the big thing Yale did for me. It also built a little Rolodex for me. It introduced me to important people.” At The Nature Conservancy, Hoose talked his bosses into giving him time to produce a how-to book about species protection called Building an Ark, and that launched him on a side career as a writer.
By 2009, when Hoose traveled to Tierra del Fuego to begin work on Moonbird, B95 was already at least 17 years old, older than any other rufa Red Knot on record. He had been recaptured three times, most recently in 2007, by a startled scientist, who at first uttered “Oh, my God,” and then went to work, quickly taking all the usual measurements. “His weight was where it should be,” he later recalled. “He had wonderful plumage. He was as fit as a three-year-old. I was holding a superbird in my hand.”
Animals can intrigue us for several reasons, but one of them is how they adapt to all the far-flung, seasonal opportunities of life on Earth. B95 and his fellow rufa Red Knots travel to Tierra del Fuego every November, Hoose writes, because the reddish-brown restinga tidal flats there are packed with juvenile mussels still soft enough and loosely enough anchored “for the tug of a ravenous Red Knot’s bill.” The long hours of daylight in the extreme south then also mean that the tidal flats are exposed for two brightly lighted feeding sessions a day.
Thus B95 can double his weight until he looks bloated and beady-eyed before migration. It’s mostly fat, which is better for long-distance flight because it packs eight times the energy per ounce as protein. At the same time, B95’s heart enlarges to pump blood to his flight muscles, and he shelves many internal organs: “His liver and gut shrivel, as do the muscles in his legs. His gizzard—an organ that grinds food—decreases in size by nearly half, meaning he will be able to eat only soft food when he stops to refuel.”
These changes also mean that B95 and his flock depend on having the right foods available on his route. But it wasn’t until May 1979 that researchers discovered rufa’s single most important feeding site on the long trip north. The flight from northern South America to the Delaware Bay is almost 5,000 miles long and can last more than six days, much of it across open water. B95 and his flock make the drop into Cape May, N.J., “panting for oxygen, with bones protruding, desperate for food.” To rebuild for the final 2,000-mile run up to the Arctic, these birds must each manage the equivalent of a human gaining 10 pounds a day. Happily, just in time for their arrival, horseshoe crabs are littering the tidal zone with their soft, nutrient-packed eggs.
In the early 1990s, however, commercial fishermen suddenly realized that the horseshoe crab mating season in Delaware Bay made easy pickings for the bait trade. “For a few unregulated years, it was a gold rush,” Hoose told his F&ES audience. “Out-of-state vehicles drove up and paid locals a pittance for every horseshoe crab they could gather.” On any given day at that time of year, 90 percent of the entire rufa population can be working the beaches of Delaware Bay, and they apparently felt the competition. Over a two-year period, from 2000 to 2002, half of all adult rufa Red Knots died.