Adult Common Crane |
The Common or Eurasian Crane Grus grus is one of only four species of crane that is not threatened.
In fact, it is increasing in Europe, and currently has a total world population
of around 500,000 individuals. In Spain we found them at a major wintering
ground at Lake Gallocanta. This lagoon in the south west of the province of
Zaragosa is the largest staging area for migrant cranes in Europe, with perhaps
80% of the entire western European population using it on passage in both
winter and spring. Left over grain and
The Gallocanta area is a large inland lake and the
surrounding areas are used for arable and grazing. Cranes use the area for
roosting in the lake which gives protection from predators at night. The birds
feed in fields in the surrounding areas on leftover grain and invertebrates.
While Common Cranes are secretive when nesting they are much more tolerant of
people outside the breeding season and are often seen feeding in fields. Even
during the breeding season, many cranes are now using much smaller wetlands
close to human habitations than in the past. Although the bulk of the Common
Crane population is still centred in Scandinavia and eastern Europe, they are
currently recolonising their former breeding range in Western Europe and the
wintering population in Spain is growing exponentially. For example, the
western wintering population in the late 1970’s was around 50,000 birds, and
today it is around 160,000+.
Cranes feeding in field at Lake Gallocanta |
When we first visited the lake in the morning we were a
little disappointed to find only a few hundred individuals. It appeared that
migration was late this year as a result of the mild autumn weather and they
were still further north. When we revisited the lake at the end of the day the
numbers had considerably increased to perhaps several thousand. They were still
rather flighty, so it seems they had only arrived during the day.
Cranes flying in to roost |
To see so many cranes at once is always a magnificent sight.
In the UK I was fortunate to be present when the first crane fledged in Norfolk
after their extinction as a breeding bird 300 years ago. Today I do not have to
travel so far to see them, as the reintroduction project in the Somerset levels
has been very successful. The Norfolk population has also grown and spread.
Today Cranes are breeding or attempting to breed in Norfolk, Suffolk,
Cambridgeshire, Yorkshire and East Scotland – all derived from the Norfolk
colonists – and also in Somerset, Gloucestershire (including at the WWT reserve
at Slimbridge), Wiltshire, Oxfordshire and Wales. The latest figures are 48
pairs attempting to breed in 2016 and 14 young raised to fledging. The total UK
population is now around 160.
Images Wikipedia, my own.
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