Habitat use and population dynamics of the Azure-Winged Magpie ...

3.3.4 Breeding individuals
Out of the 26 banded individuals that bred 6 in this colony, at least four were individuals known to
be born into this colony (2008 chicks). Three females and one male banded as adults, bred for
three consecutive breeding seasons (Table 3.11). Only two of the females raised chicks
successfully in all three years. The third female bred and raised chicks successfully in the first
two years, but in the third year she died whilst incubating. The male bred successfully in 2008
and 2009, but failed to fledge chicks in 2010. In 2009, two yearlings attempted breeding but only
one succeeded in fledging chicks.
13 banded individuals (eight females and five males) bred more than once between 2007 and
2010 (Table 3.11). Based on the visual estimation of colony sizes from 2007 to 2010 (beginning
of breeding season), 25.9 % of adults bred in 2007, 52.9% of adults bred in 2008, 48.8% of adults
bred in 2009, and 66.7% of adults bred in 2010.
The number of individuals attempting to breed between 2007 and 2010 was similar (on average
16 birds; r 2 = 0.47, P = 0.859; Fig. 3.16). However, the number of individuals that successfully
fledged chicks was lower, apart from 2007. There is a significant decrease of individuals
breeding successfully (r 2 = 0.949, P = 0.017).
All individuals that attempted to breed in 2007 were successful in fledging chicks (Fig. 3.16 &
3.17). There were more successful breeders than unsuccessful breeders in 2008 and 2009. 2010
had a similar number of successful and unsuccessful breeders (six individuals each). The
unsuccessful breeders did not show any significant change in numbers over the four-year period
(r 2 =0.400, P = 0.225; Fig.3.17).
6 Bred include birds that had laid eggs and/or hatched chicks, but didn’t necessary fledge chicks.
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