The months of April and May often turn up rare visitors, birds that have
overshot on their spring migration and ended up further north than intended.
One of the species well-known for such overshooting is the Purple Heron, at
least one individual of which has already be seen in East Anglia this spring.
The Purple Heron is a locally occurring but widespread species, breeding from
northeast France and the Netherlands east across Europe, into Asia and south
into Africa. Birds winter to the south of the breeding range and those breeding
in Europe cross the Sahara (a desert crossing of some 30 to 60 hours duration)
to winter in sub-Saharan Africa. It is because the species is migratory in
habits that some individuals end up reaching Britain each year.
Most of the records of Purple Herons in Britain come from East Anglia,
Kent and East Sussex, and most involve single birds. However, a party of four
Purple Herons, accompanied by a solitary Grey Heron, were seen to arrive at
Salthouse from the northeast on 1st June 1998. The birds circled
over the village briefly and then departed inland. The species can prove a
frustration for the birdwatcher, often only stopping at a site for a single day
and also tending to remain elusive during its stay. Your best chance of seeing
the bird is either in early morning or close to dusk, as it flies between
feeding and roosting areas. When foraging, the heron can be very difficult to
see, since it tends to stand motionless, waist deep in water, within dense
vegetation (like a stand of reeds). Large reedbeds are a clear draw and this
may be why the RSPB reserve at Minsmere seems to do so well when it comes to
attracting them (a position on the east coast does not hurt either). In 2007,
at least three birds were present in the second half of May, with two
individuals seen to display on several occasions. Any hopes of a breeding
attempt were dashed, however, by the arrival of bad weather.
The Purple Heron is noticeably smaller than the more familiar Grey Heron
and sports rufous brown and grey plumage, mixed with areas of black and white.
Since the species is most often seen in flight, when size can be more difficult
to determine, there is scope for confusion with Grey Heron. Generally speaking,
a Purple Heron in flight appears as a wholly dark bird while the lighter
coloured Grey Heron shows contrast between the grey wings and the white body.
It is worth casting a careful eye over any herons that you see over the coming
weeks, just in case they prove to be something more exotic.
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