Beauty & the Beast
Hawker Dragonflies:
Their characteristic hawk-like habit of restlessly patrolling a territory gives hawker dragonflies their name. The Hawkers territory is a stretch of river or lake, which the male defends against intruders, jostling with rival males and other species, and courting female hawkers which enter it.
Hawkers tend to have a larger wingspan and slimmer, longer body than darter dragonflies. Male hawkers are usually more brightly coloured than females – which, since dragonflies keen-sighted and sensitive to colour, is valuable in sexual recognition. It is also useful for females to be less conspicuous to birds that prey on them, including flycatchers, bee-eaters and hobbies. Colour difference between the sexes is not universal, however, and scent and behaviour are probably sexual recognition factors used at close quarters. Some dragonfly colours are true pigments; others are the result of light diffraction in the body’s cuticle, or outer layer.
Their characteristic hawk-like habit of restlessly patrolling a territory gives hawker dragonflies their name. The Hawkers territory is a stretch of river or lake, which the male defends against intruders, jostling with rival males and other species, and courting female hawkers which enter it.
Hawkers tend to have a larger wingspan and slimmer, longer body than darter dragonflies. Male hawkers are usually more brightly coloured than females – which, since dragonflies keen-sighted and sensitive to colour, is valuable in sexual recognition. It is also useful for females to be less conspicuous to birds that prey on them, including flycatchers, bee-eaters and hobbies. Colour difference between the sexes is not universal, however, and scent and behaviour are probably sexual recognition factors used at close quarters. Some dragonfly colours are true pigments; others are the result of light diffraction in the body’s cuticle, or outer layer.
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Also in: Insects and the like
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