CURLEW
The photograph on this page is © Peter Beasley ARPS and the drawing is by Lizzy Hibbert © Upper Onny Wildlife Group
Curlews
return from their winter quarters on coastal estuaries to their breeding grounds
during March. Their far carrying, bubbling call, is perhaps the most evocative
of all spring bird sounds, and Curlews are very conspicuous during this
territorial display flight.
They are large birds, mainly grey –
brown, with a white speckled breast. Their body is about the size of a
Woodpigeon, with much longer legs, but their most noticeable feature is the thin
down-curved bill, which adds another 10 -18 centimetres, around a quarter of
their total length. They have a conspicuous white triangular rump in flight.
Curlews usually nest in rank vegetation, such as
unimproved grassland and heather moorland, or in rushes or
tussocks, on rough grazing or adjacent to pasture or arable crops. This provides
thick cover for the sitting bird and eggs, and for chicks.
Curlews feed on open damp pasture and meadows, using their
long bill to probe wet, boggy areas to find the
invertebrates that they live on. They are ground nesting birds, so all-round
visibility is important in avoiding predator attacks, and Curlews are only found
in open landscapes.
The
first clutch, almost always four eggs, may be laid from
first half of April onwards, but usually
around the end of April or beginning of May, with an interval of 1-2 days between each egg.
Incubation usually takes 27–30 days. Chicks leave the nest immediately after
hatching, and feed themselves, but they do not fly until 32–40 days later.
They are well camouflaged, and very hard to find, but they are still vulnerable
to predators until they can fly.
Display
flights occur frequently up until mid June, but continue occasionally up until
the second week in July. As later display flights are associated with nests that
are still active, but most pairs have ceased displaying by the time their chicks
would only be a couple of weeks old, this is probably an indication of a high
rate of loss of nests and unfledged chicks.
Nationally, Curlew is in serious decline, and is on the Amber
List of Birds of Conservation Concern 2002-2007.
The Birds of Wet Meadows Survey
2002 found a 38.9% decline since 1982. The
Repeat Upland Bird Survey 2002
revisited nine study areas that had previously been surveyed between 1980 and
1991, and also reviewed data from four other upland areas. It found an estimated
decline of over 50%, with a 41% decline in only seven years between 1987 and
1994 at one site in North West Wales.
In
the
In
In
the uplands, breeding bird surveys on the Stiperstones and the Long Mynd have
shown a catastrophic decline of Curlew in the last 10 years.
The
Long Mynd Breeding Bird Project found 11-13 pairs in 1995, declining to 7-8
pairs in 1998, 3 pairs in 2002 and 2003, and only 2 pairs in 2004. Not
surprisingly, there were very few confirmed breeding records, even for such a
conspicuous bird, indicating very poor breeding success.
Five
breeding pairs were recorded on the Stiperstones in 1995-96, but the species had
apparently ceased breeding prior to 2000, and certainly none were found during
Breeding Bird Surveys there in 2002 and 2004.
Curlews
have also declined considerably in the
A
comparison of the 2004 Survey Results with the relevant section of the
distribution map in The Atlas (1992)
shows a marked decline of the species locally. The Atlas map shows the evidence of breeding found in each Tetrad
between 1985 and 1990 - confirmed breeding or probably breeding, or present or
absent in the breeding season. The records from this 2004 Survey can be mapped
in the same way. The comparison
between the two surveys is shown in Maps C and D on the previous page.
It
will be seen that, during The Atlas (1992)
period, Curlew were recorded in every single one of the 30 Tetrads covered by
the 2004 Survey, with confirmed or probable breeding in 28 of the 30 Tetrads.
In 2004, this species was breeding in only 20 Tetrads, and was not
recorded at all in seven of them.
Nationally, the population decline is attributed primarily to agricultural intensification, leading to changes in the breeding habitat:
Land drainage, leading to a reduction in the amount of rank
vegetation for nest sites, and to a reduction in the quality and quantity of
invertebrate
food supply in the wet meadows.
Other practices used to
“improve” grassland, including control of “weeds” such as rushes
that are used as cover for nests, and rolling and chain harrowing that
destroys nests and chicks.
Increased use of fertilisers, which accelerates the transfer
of the water in the ground into the growing grass, thereby reinforcing the
effect of drainage.
Production of silage, rather than hay, which is cut earlier
and more often, thus increasing the destruction of eggs and chicks.
More intensive grazing, and
higher stocking levels, which reduces nest cover still further, and, in
addition, increases the risk of nests being trampled.
For
example, studies elsewhere found one pair per square kilometre on dry pasture
and arable land in Scotland, compared with 2.4 - 2.9 pairs per square kilometre
on rough grazing in the same area; while densities on marginal farmland sites in
Northern England declined from ten pairs per square kilometre to one pair per
square kilometre as the proportion of improved grassland on the sites increased.
Drainage and re-seeding means that even the
In the
If a pair loses its first clutch, a replacement may be
laid, 4 - 15 days after the loss. Thus Curlew nests and chicks are vulnerable to
agricultural operations from early April to late July. Rolling of grassland was
first noted in the
Curlews generally suffer from poor breeding success, but they are particularly vulnerable in the Shropshire Hills because intensive sheep grazing has reduced the available cover for nests and chicks. More importantly, predation has also played a part in the decline - the smaller number of Curlews, with the reduced amount of nesting cover, mean nests and chicks are ever more vulnerable to the increasing number of predators, particularly Corvids and foxes. The increased availability of carrion from dead sheep has almost certainly increased the numbers of these predators considerably. Though no counts have been made, Crows now breed at very high densities. For comparison, it is known that the County population of Raven, another potential but less numerous predator, has increased fivefold in the 13 years since The Atlas was published, as a result of increased availability of carrion. This food source will also have benefited all the other, more numerous, predators, to the detriment of Curlew.
It
is not known whether the declines on the Stiperstones and Long Mynd are
primarily due to high levels of predation of nests and chicks on those sites, or
a migration of breeding pairs down onto the adjacent farmland, which might
appear to be more suitable breeding habitat, but where breeding success will
also be poor as a result of agricultural operations as well as predation.
In short, there are many fewer places in
However,
help may be on the way. The current
agriculture subsidy scheme, which created the modern farming conditions which
Curlew find intolerable, is being phased out.
The new system, announced by the Government’s Department for
Environment, Food and Rural Affairs (Defra) on
Defra,
the AONB Office, the National Trust, English Nature, and a whole range of other
conservation organisations are working together to encourage landowners to take
advantage of the new subsidy scheme, and farm for the benefit of Curlew and
other bird species, not agricultural surpluses.
The Shropshire Ornithological Society is trying to
locate all Curlew breeding sites, to provide advice to Defra and farmers on the
sites that should benefit from the new subsidy scheme.
If you see Curlew anywhere, during the breeding season (mid – March to
mid July), please submit a record to the
County