A few days ago, a grim ornithological mystery came across my computer screen. A photo of a chunky, yellowish bird found dead in the wrack line at Hardings Beach in Chatham. It was originally sent to Mike O’Connor at Birdwatcher’s General Store in Orleans, who identified it as one of the most sought-after and hardest to see birds in North America, a Yellow Rail. And how exactly it ended up on that beach is anyone’s guess. But that’s not that much of a mystery – it was in a marsh somewhere nearby and didn’t survive the winter, eventually washing out with the tide. The real mystery is, well, pretty much everything else about Yellow Rails.