Ka. Tarvin et Kg. Smith, MICROHABITAT FACTORS INFLUENCING PREDATION AND SUCCESS OF SUBURBAN BLUE JAY CYANOCITTA-CRISTATA NESTS, Journal of avian biology, 26(4), 1995, pp. 296-304
We examined how microhabitat features surrounding nest-sites influence
probability of nest predation by testing unique predictions generated
from the ''distance to human activity, the ''habitat complexity, and
the ''multiple nest-site'' hypotheses. During spring and summer 1990,
we quantified nine features of nest-sites and 11 features of 0.1 ha ne
st-patches surrounding 42 nests of suburban Blue Jays Cyanocitta crist
ata in Fayetteville, Arkansas, to determine differences associated wit
h depredated and successful nests. Overall nesting success was 52% and
mean daily survival rate of nests was 0.983 (+/- 0.004 SE). Twenty-fo
ur nests fledged at least one young, and 18 failed as a result of nest
predation. Features of the nest-site, including nest height, size of
the nest tree, and nest concealment, were not related to nest predatio
n, although distance from a nest to the nearest building was inversely
related to duration of nest survival. The latter relationship suggest
s human activity may decrease nest predation in suburban areas. Densit
y of vegetation surrounding nests did not influence nest fate, thus pr
oviding no support for the habitat complexity hypothesis. Instead, fai
led nests occurred in patches containing fewer trees of the same speci
es, size class and vine cover as the nest tree. Because this pattern w
as not an effect of size or species of either the nest tree or neighbo
ring trees, nor an effect of vines in the nest tree or neighboring tre
es, it provides support for the multiple nest-site hypothesis.