One of the few things known about the Nordmann’s greenshank is that it is one of the most endangered shorebirds on earth. No one had studied the bird in depth since 1976, and its nesting habitat remained a mystery.

But this summer, an American graduate student and Russian ornithologists spotted a pair of Nordmann’s greenshanks in a larch forest near a coastal bog in far eastern Russia. They shot video of one in a nest, measured and photographed four eggs and tagged seven adult birds, a few which have been spotted again as they migrated south across Asia.

“The moment of discovery — it was pure joy,” said Philipp Maleko, a graduate student at the University of Florida, who tracked the birds for nearly two months this summer, wading through the bog and forest to spot the nest. In addition to fighting off hordes of mosquitoes, the research team traveled with an armed guard to ward off bears and wolves.

Their research marked the first in-depth investigation in decades of the Nordmann’s greenshank (Tringa guttifer), a pigeon-size bird named for a 19th-century Finnish biologist and parasitologist.