March 9 Chatham Bay, Cocos Island, Costa Rica retrieve, as the rolled, or when wounded, ran down hill. Often one couldn't see where they hit. On the flats recovery was no problem. The finches and flycatchers were very common here, the finches showing a density, comparable to the birds on the Galapagos. It was not unusual to see 8 or 10 in a small group working high in a tree, and after awhile one male would be- gin to chase others away. I saw only 2 or 3, all ? plum- aged, birds lower than 4 feet, and well over half the birds were of 25 ft from the ground. They did come lower when I squeaked. Saw one pulling a cicada apart like yesterday. The seems to probe bark and seem were seen tearing dead leaves apart. Two were seen "flycat- ching." A ? spent nearly a minute in the air in a slow sinuous flight apparently chasing something, then turning to another object and chasing that. It landed on a large bromeliad covered branch, foraged there, and then went off on a shorter similar flight. Later I saw a ? plumaged bird doing the same thing. The ?'s very frequently show a tail drooped & spread, wing drooped posture, with the feathers of the breast and body fluffed somewhat, and so. They forage in a wing- drooped, Tail up posture. The two postures look like: 233