Plight of Britains Farmland Birds
farmland birds have suffered alarming declines over the last twenty-five
years. It would appear that their decrease in numbers coincides
with a period of rapid intensification in farming in the mid-1970s,
and they have continued to steadily drop in numbers ever since.
This spring and summer the RSPB, in conjunction with a number of
other organisations, has organised a nation-wide survey intended
to get a better idea of the status of our farmland birds, and to
work with farmers to make their land more wildlife friendly.
There is thought to be six main reasons for the decline in farmland
1) Loss of
wild food-plants as a result of herbicide use
2) Change from spring-sown to autumn-sown cereals and the subsequent
loss of winter stubble.
3) Insecticide use reducing invertebrate populations.
4) Conversion of pasture to arable land and the resultant decline
in soil invertebrate numbers.
5) Land drainage making soil dwelling invertebrates less accessible.
6) Availability of nest sites due to removal of hedgerows.
of these factors are a result of agricultural intensification, and
they have affected different species to varying degrees. The Tree
Sparrow (Passer montanus) right
is the species that has experienced the most dramatic decline in
numbers, over a 95% reduction in abundance. The main cause of this
decline is the reduction of seed-supply through destruction of food-plants,
usually as a consequence of herbicide use. Along with the loss of
winter stubble, it means that food supplies are scarce all year-round
which has resulted in a probable increase in the mortality of full-grown
birds. Those adult birds that do survive harsh winters on reduced
food supply then had difficulties locating suitable nest sites,
as the hedgerows they had relied on have been lost.
common farmland bird that has hit hard times is the Grey Partridge
(Perdix perdix). This species has been badly affected by the use
of herbicides and its subsequent reduction of food-plants. The loss
of vital insect supplies by insecticides has resulted in an inadequate
rate of chick survival. The lack of suitable nest sites has also
resulted in increased predation by corvids and mammals on the eggs
and chicks. The Lapwing (Vanellus vanellus) has also suffered. A
combination of insufficient chick survival and loss of nesting habitats
has resulted in a 40% drop in numbers since 1970. A switch from
spring-sown crops to autumn-sown crops causes grass and crops to
be too mature and dense to provide suitable nesting sites. Land
drainage has affected their food supply by drying out the topsoil
and making invertebrates less accessible, and earlier harvests mean
that lapwing nests are often destroyed by heavy machinery.
Corn Bunting (Miliaria calandra) left
has declined by 85% because of a severe reduction in areas of barley
now sown, a crop which is a favoured site for nesting. The adult
birds have also suffered losses because of the loss of winter stubble
fields and the use of herbicides. It is thought that adult mortality
in the winter months is the main cause for a decline in numbers.
Many other once familiar birds have also suffered recent declines;
Linnets by 54%, Yellowhammers by 54%, Turtle Dove by 70% and Skylark
practical management the RSPB is hoping to reverse the current decline
in numbers of farmland birds. Bird Aid is a three-year emergency
feeding experiment designed to monitor effects of providing additional
food in the winter to farmland birds, across the United Kingdom.
The project is primarily aimed at helping Tree Sparrows and Corn
Buntings, as they appear to be two species that are suffering adult
mortality as a result of a change in farming methods. Bird counts
in both summer and winter aim to see whether feeding birds during
the winter makes a difference to breeding populations. It is hoped
that agri-environment schemes will also increase the numbers of
farmland birds. These are government schemes that make payments
to support farmers retaining and improving the quality of their
farm from a wildlife point of view. Payments can be given for a
variety of different things, such as leaving winter stubble, sowing
mixtures of seed bearing crops, and not spraying right to the edge
of the field (good feeding habitat for birds).
A separate scheme
currently being undertaken in Dorset this year is the Purbeck bio-diversity
scheme. The project has been running for five years and is helping
to protect declining habitats and species (particularly farmland)
by offering advice to farmers and landowners on management and agri-environment
schemes that help wildlife. The information gathered from the survey
will be analysed and compared against an identical survey that was
carried out in 1999. The results from the new 2002 survey should
enable important areas for farmland birds in the Purbeck to be identified,
and target conservation work where it will have the most beneficial
& Farmer Alliance scheme being undertaken nation-wide this year
hopes to promote good relations between conservation groups and
the farming community. Each farm that is surveyed receives a computerised
map showing the territories of all birds of conservation concern,
plus a full list of bird species seen on the farm. The farmer will
also receive a certificate of participation and information on how
to help farmland birds. It is important to remember that no one
is blaming the farmers for the decline of farmland birds as the
intensification of farming has been driven by agricultural policy.
The aim of the project is to strengthen the links between the RSPB
and the farming community, and to help farmers achieve the twin
aims of food production and conservation, to give Britain's farmland
birds a brighter future.
Portugal is a marine biology graduate from Aberystwyth.
He lives in Dorset and has been birdwatching around the country
from a very young age. He starts a job with the RSPB shortly,
and begins a PhD in Glasgow at the end of the year.