3.1. General pattern of behaviour profiles
Not surprisingly, the birds spent most time in activities relating to
obtaining food including diving, head-dipping, eye-submerging, and
vigilance, and food handling, preening and other social activities such
as intraspecific interaction took only a fraction of a foraging bout
(Table 3).
For each foraging activity, diving took the longest time with mean
duration of 13.13 seconds (SD = 7.12) followed by swimming (5.22 ±
6.59s), preening (4.69 ± 4.17s) and vigilance (4.06 ± 2.69s),
socializing (3.83 ± 3.12s) and food handling (3.19± 4.77s). While the
frequency for head-dipping and eye-submerging were the highest (4.40 ±
5.51 and 5.75 ± 5.48 times/minute, respectively), they took the least
time (2.60 ± 0.92s and 1.89 ± 0.07s, respectively). Moreover, the
standard deviation (SD) of the attributes (i.e. frequency, duration and
proportion) for most behaviours were relatively large comparing with the
mean, suggesting the highly variable behavioural profiles of the
bird.
Table 3. Summary of the foraging behaviours of M. squamatusduring wintering in Shangqing River, China