| Summary: | Maintenance and Update Frequency: notPlanned Statement: Great cormorants Phalacrocorax carbo carbo rearing small chicks (during the first week after hatching) were caught on their nests at Qeqertaq (69 30' N, 54 05'W) in the Diskofjord area, Disko, west Greenland, between June 2002 and July 2002. Little penguins Eudyptula minor novaehollandiae, also rearing small chicks, were captured in wooden nest-boxes (see Klomp et al. 1991) where they normally breed at Penguin Island (32 16' S, 115 21' E), Rockingham, Western Australia, in August 2001 and 2002. Statement: The diving behaviour, body posture and swimming activity of birds were monitored using cylindrically shaped data loggers with domed heads (M190- 2GT, Little Leonardo, Tokyo) that weighed 16g (15 × 52 mm) and had a 128 Mb flash memory into which data were stored with 12 bit resolution. Depth was measured by a piezoresistive pressure sensor (FPBS-82A, Fujikura, Tokyo) up to 190m, with a precision of +-1 m and a resolution of 0.05m. Acceleration was measured along perpendicular axes by a capacitive accelerometer (ADXL202E, Analog Devices) between 0 and +-30 m s-2. This sensor measures both dynamic (e.g. vibration) and static accelerations (e.g. gravity). Values recorded by loggers were converted into acceleration with linear regression equations. To obtain the calibration equations, values recorded by each logger set at 90° and -90° from the horizon were regressed on the corresponding acceleration (9.8 and -9.8 m s-2, respectively). In our study, loggers were attached to the lower backs of birds with waterproof TESA tape. Acceleration signals were measured along the surging (along the main body axis of birds) and heaving (dorsoventrally) axes. Data were recorded at frequencies of 1 Hz for depth and 16 Hz on each acceleration axis. Credit Funding was through Institut Polaire Français Paul-Emile Victor through Grant No. 388 to D.G. and by the Centre National de la Recherche Scientifigue, as well as the Japan Society for Promotion of Science, Tokyo, Japan ...
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