THE SEX ISSUE
MASTER OF CRAFT
BAYA WEAVER Ploceus philippinus
2 The weaver family get their name after their ability to weave elaborate
nests, which vary in size, shape and material depending on the species.
The Baya Weaver chooses branches of thorny trees or palm trees above
the water to weave grass leaves into their gourd-shaped nests, which can
be as big as a football. As they’re a social species, they don’t like to nest
alone – with up to 60 pairs nesting together in a single tree and more
than 200 in some colonies. Found across Southeast Asia and the Indian
subcontinent, their breeding season coincides with the monsoons so
researchers believe their nests are often located on the eastern side of the
tree because it offers protection against the heavy rains.
Photo tahirsphotography/Shutterstock
METICULOUS
ANNA’S HUMMINGBIRD Calypte anna
2 This North American hummingbird
builds tiny luxurious nests in trees or
shrubs, mostly using plant fibers,
downy feathers and animal hair, bound
together by spider silk. They finish it off
camouflaging the exterior with plant
debris, moss or bits of lichen. The
nest size ranges from 3.8 to 5.1 cm
in diameter, about the size of a small
espresso cup, laying two eggs the size of
a coffee bean.
NEST
FEST
Photo Mick Thompson/Flickr
SPARTAN
WHITE TERN Gygis alba
Collecting grass, twigs, mud? Too much
like hard work. Why bother building a nest
when you can just lay your eggs on top of
any branch? The White Tern’s minimalist nest
consists of… literally nothing. A knot or crook
on a tree branch is all it needs to incubate
its single egg. Scientists speculate that they
have evolved this behaviour as a result of
nest parasites, found to be less common if
there’s no nest in the first place. 3
When thinking about bird nests, most people may imagine
the regular bowl-shaped receptacle of twigs and leaves,
but birds’ nesting behaviours are as diverse as their courting rituals.
Here are eight hand-picked nesting styles from around the world
Irene Lorenzo
Photo 18042011/Shutterstock
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BIRDLIFE • JUNE 2017