B95 is the tag an Argentinian placed on a red knot's leg 18 years ago, in 1995. The individual male has since outlived most of his species and continued to make a journey that has been carefully recorded from the Canadian Arctic to the tip of South America. Many sandpipers migrate across great distances, but this knot is spectacular.
He weighs 4 ounces (113g) and has flown a minimum of 320,000 miles (515,000km). The "Moonbird" epithet arises from the distance to the Moon and half-way back that this measures. Predatory falcons, bad weather and fatigue kill many of the formerly numerous knots as they carry out this enormous migration. The population is also decreasing rapidly, so his survival could be important - if we can discover how he keeps on going.
It's likely that human encroachment on the tidal flats he inhabits has been responsible for many of his fellow-migrators' deaths. In Delaware Bay he has been observed feeding on the numerous green eggs of horseshoe crabs in May. They themselves are now threatened after overfishing locally and, again, human encroachment.
Local authorities in New Jersey and in Delaware have been forced into action, as the red knot was predicted to become extinct as long ago as 2003. So the knots have gone hungry in many coasts close to human interference and may have died because of it.
The ultimate tribute to this bird's achievements is that B95's biography has been written. "Moonbird: A Year on the Wind with the Great Survivor B95," is to be published in July by author, Phil Hoose.