by
Jim Cassels
on Fri 13 Jun 2008 05:39 PM BST |
Permanent Link
|
Cosmos
Nightjars
are birds of legend including the widely held belief that Nightjars sucked the
milk of grazing animals. Thus its other
name “Goatsucker”.
In
reality, Nightjars feed on insects, mainly larger moths. Nightjars migrate to Britain from Africa
and return there after rearing their chicks. They arrive in Scotland in May and early June when
the moth population explodes. They are
most active at the same times of day as moths, at dawn and at dusk. With their large eyes, huge gape surrounded
by “whiskers” they are well adapted for catching their prey.
Nightjars
are rarely seen during daylight. They
remain motionless on the ground, relying on their amazing camouflage - feather
patterns that look like dead leaves and old tree bark - to avoid detection. But at night when they are 'churring', they
usually perch on the branch of a prominent tree and can be picked out against
the night sky. When flying, Nightjar
swoop and flap around their territories, often coming very close to any
observers. Males have prominent white
markings on the wings and tail, and females have brown markings that are much
less prominent. These stand out even at
night, so it is often possible to identify the bird's sex. People most often encounter the Nightjar's
distinctive sound. Males perform a
prolonged churring call ('Nightjar' means night-churr) that may go on for
several minutes, varying in pitch and volume. When the birds stop churring,
they are often in flight and two other sounds are frequently heard. The first is a rather soft 'coohwick' given as
a single note and thought to be a contact call. The second is a slapping or hand-clapping
sound caused as the birds clap their wings in flight.
Hearing
a Nightjar used to be a not uncommon experience in Arran,
but in the latter part of the twentieth century there was a decline. They finally disappeared from their last
reported area in Brodick
Country Park
in 1998. Until last year there were no
records on Arran this century. Nightjar like forestry 'clear fell' sites -
where all the trees have been cut down - and replanted areas, until the trees
are around 15 years old. The increase
of these areas in Arran may encourage the
re-establishment of the Nightjar. These
new heaths provide good nesting cover, plenty of perches and an abundant food
supply. At night, radio-tracked birds
have been recorded leaving their territories to feed in other habitats, such as
deciduous woodland and wet pasture.
Encountering
Nightjar in the gloaming is a magic birding moment, if you can thole the
inevitable midges.