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

Population Dynamics
Nest predation
I tried to determine the frequency of nest predation and the species responsible. Tracking pads
were tied to tree trunks or branches leading up to nests. This was done only in June 2010 when
the chicks or eggs were still in the nests as I arrived too late in 2009 for the breeding season. Two
tracking pads were placed in four Padus asiatica bushes with active nests, two at the main
breeding area, and two at the ‘Padus Patch’ area (see Results for nest locations). Tracking pads
consisted of a piece of rectangular cardboard (with one smooth side and a rough side) about 25 x
10cm, spread with tracking ink (Black Track, Pest Control Research Ltd) in the middle. My use
of tracking pads was to mimic the function of tracking tunnels used regularly by the Department
of Conservation and pest control operators in New Zealand. Potential predators approaching
Cyanopica cyanus nests have to walk over the ink, thus leaving footprints, and I could then
determine which species were possible predators of Cyanopica chicks and eggs. Tracking pads
are, however, vulnerable to extreme weather conditions—when it is hot the ink will dry quickly
and during wet weather, the ink washes off with rain. Tracking pads were checked once every 2-3
days and the ink reapplied at the same frequency or when deemed necessary due to weather
conditions.
Population dynamics
Data was obtained from Gantulga Bayandonoi, a Masters student from National University of
Mongolia who worked on the breeding biology of Cyanopica cyanus over the breeding seasons
(May-July) of 2007-2009. In 2006, Jenny Beyer from Georg-August University, Germany,
banded birds as work for her diploma thesis. A total of 126 individuals were banded in the period
of 2006-2010. All field work for these projects was done between May and September. Each bird
was banded with a metal band with a numbering system determined by Institute for Bird
Research (Vogelwarte), Wilhemshaven, Germany, and a unique colour band combination. The
colours used were Red, Yellow, Green, Blue and White. The colour bands were always read from
the left leg to the right leg of the bird, and always from top to bottom.
Gantulga Bayandonoi obtained nesting and population data while doing nest monitoring between
2007 and 2009 (Gantulga, 2010). Nests were located in the beginning of the breeding season and
monitored subsequently until all chicks had fledged. Adult birds and fledglings were captured
using mist nets of either 6 or 12m length with 4-6 pockets. Nestlings were banded when they
were 13-15 days old. The sex of banded adult birds that were caught near the nest was
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