| Summary: | Maintenance and Update Frequency: notPlanned Statement: Data-loggers were fitted to four Little Penguins in August 2002. All birds were nesting on the central part of Penguin Island, Rockingham (32 16'S, 115 21'E), Western Australia, in rectangular, wooden nest-boxes, allowing easy capture of the adults and checking of the chicks. Nautical dusk and dawn for the study period were taken to be 0550 h and 1848 h (local time), respectively, (http://lychnis.imcce.fr/cgi-bin/levcou.cgi). Birds were captured at their nest site, either at night or before departure for sea early in the morning. The sex (determined from the bill depth; Gales 1989), breeding status and the mass of both the adult and its chicks were noted. Loggers were then attached using waterproof (Tesa) tape (Wilson et al. 1997a) on the median line of the birds back, near the tail so as to minimize drag (Bannasch et al. 1994). The attachment of the logger was completed in <5 min and birds were released at the entrance of their nest-box. Statement: Time-budgets and activity patterns of birds were recorded using miniaturized, cylindrical, four-channel data loggers (M190-D2GT, 12 bit resolution, 52ยท15 mm, 16g, Little Leonardo, Tokyo, Japan). The absolute accuracy for the depth sensor was 0.1m. The devices simultaneously monitored depth (1 Hz) and acceleration (16 Hz) along the longitudinal (surging) and dorso-ventral (heaving) axes of the birds. The units contained sensors capable of measuring both dynamic acceleration (e.g. vibration) and static acceleration (gravity). In the absence of movement, values of static acceleration ranged from +1 to -1 G. For instance, a vertically upright logger would correspond to values of 0 G on the heaving axis and -1 or +1 G on the surging axis, depending on whether the logger was head-up or head down, respectively, (see Yoda et al. 1999 for technical details). Statement: Calibration sessions were conducted at the Perth Zoo, Western Australia. One Little Penguin was equipped with an accelerometer, attached using ...
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