The other day, a trip to Bristol to meet up with the BBC SpringWatch
Team delivered an unexpected surprise in the form of a pair of urban Ravens. We
had hoped that we might see an urban Peregrine, as the city now supports
several pairs, but proved to be disappointed by the lack of birds at a regular
haunt. Of course, the Ravens more than made up for this as they are a still a
rare visitor to Norfolk and to see them in an urban setting was totally
unexpected.
The return of the Raven to our urban centres comes after a gap of many
centuries and reflects a broader recovery of its breeding population. Up until
the end of the nineteenth century you would have been able to find Ravens
breeding in just about every English county, but the ongoing persecution soon
saw the species lost from most of its former breeding range. Ravens are
scavengers for the most part, taking carrion or foraging among the refuse of
our society. They also take a surprisingly large amount of plant material,
including cereal grains, berries and even grasses, together with invertebrates,
small mammals and small birds. It is the preference for carrion, especially
that associated with livestock, that has contributed to their persecution over
the years but a more enlightened attitude has aided their recovery.
It is the western strongholds that have driven the recovery, the
population expanding slowly but steadily eastwards into southern and central
England. Established pairs tend to remain within their breeding territories
throughout the year but young birds undertake larger movements and it is these
individuals that have colonised new areas. Some of these dispersive movements
can be substantial as highlighted by the recovery of a juvenile Raven at West Stow
(just over the border into Suffolk) back in 1988; this individual had been
ringed as a chick the previous summer in Ireland. Breeding pairs are now
established in Sussex and Kent and to the north of London, but the species is
still some way off re-establishing itself in East Anglia.
Bristol it seems, now has an interesting mix of larger birds. In
addition to the Peregrines and Ravens, there is a sizeable population of
inland-breeding gulls, dominated by Herring Gull and Lesser Black-backed Gull.
For me it is the Ravens that steal the show. The sheer size of these birds – we
were lucky enough to see them alongside a Carrion Crow, which they dwarfed –
and the wonderful croaking call, deliver a powerful sense of character. With
luck, we will see them return to Norwich one day, our attention caught by a
croaking call and an upward glance will reveal the silhouette of this striking
bird.
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