Nest site selection
There was a significant species difference in whether a wasp nest was
found near the nest (Fisher’s exact test, p < 0.001, Fig. 4a).
Nests were built near a wasp nest more often in red-cheeked cordon-bleus
(80%, 12 of 15 nests) than in blue-capped cordon-bleus (4.7%, two of
43 nests). Blue-capped cordon-bleus tended to use weaver nests (23.3%,
10 of 43 nests) more often than red-cheeked cordon-bleus (6.7%, one of
15 nests), although it was not statistically significant (Fisher’s exact
test, p = 0.257; Fig. 4b). The only weaver nest used by the red-cheeked
cordon-bleus was accompanied by a wasp nest (Fig. 2c).
As far as I observed, there seemed to be no clear difference between the
two cordon-bleus in their preference for nesting sites—the
distribution of nest locations overlapped between the two species (Fig.
3). Further, there were no significant species differences in the types
of nested plants and the height of the nest positions. Both species
mainly nested on the Acacia /Acacia -like trees
(> 80%; 39 of 43 nests in blue-capped, 13 of 15 nests in
red-cheeked) and occasionally on other shrubs (two of 43 nests in
blue-capped, zero of 15 nests in red-cheeked) and broad-leaved trees
(two of 43 nests in blue-capped, two of 15 nests in red-cheeked). There
was no significant difference in the proportion (Chi-square test:
χ2 = 1.933, df = 2, p = 0.3803). The height of the
nest position was also not significantly different between species
(blue-capped: median±SD = 255.5±72.8 cm, red-cheeked: 250±72.0 cm;
Student’s t-test: t = 0.119, p = 0.906).