At Miranda last weekend the Eastern Bar-tailed Godwits were looking decidedly fat and it won't be long before they begin to clump into flocks of about 20 - 50 and quietly and unobtrusively leave the Firth of Thames to begin their incredible journey north to Alaska for the summer. By April they will hopefully have found their Yellow Sea estuary* still rich in the marine worms they need to regain their weight. And then, after their stop of 4 weeks or so, they'll continue on the last leg to the Alaskan lowland tundra to mate, nest and raise their chicks.
*If it hasn't had a seawall built around it and been drained to make it useful. To people.