Test of barometric, pitch and roll sensors.
Plumage, bill colour and shape distinguish Sterna bergii from S. bengalensis.
Sterna albifrons colony re-establishing at new locality.
Considerable variation between colonies and years.
Greater reaction of Anous tenuirostris melanops handled in previous year.
Pelsaert Island, Houtman Abrolhos, Western Australia, was visited between August 1991 and February 1992. Observed and estimated laying dates reveal that most laying occurs between August and November.