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Press Releases - March/April 2008
Item 6
No. 2008/03/11
March 2008
Potatoes come to rescue of Yellow Wagtails
The British Trust for Ornithology has
just published results from the latest study into the breeding success
of the Yellow Wagtail. In his article – Spuds they like –
James Gilroy explains that potatoes are coming to the rescue of
this amber-listed species of conservation concern.
Yellow Wagtails migrate to Britain from West Africa to breed during
the summer months – the first birds should be returning any
day now. They were once a familiar bird, feeding at the feet of
grazing animals in pasture and wet meadows, but the number of Yellow
Wagtails has declined by an estimated 65% in the UK since 1970.
The results of a Lincolnshire study undertaken by James Gilroy of
the University of East Anglia are published in the latest BTO News
(the membership magazine of the British Trust for Ornithology).
According to Dr Gilroy’s research, Yellow Wagtails need to
have two nesting attempts each year if they are to raise sufficient
youngsters to stem the decline in numbers. Yellow Wagtails nest
on the ground; raising their first broods in autumn-sown cereal
crops but switching to other crops in June and July, when cereal
crops become too tall and impenetrable.
As Dr Gilroy explains: “When Yellow Wagtails first return
to arable farmland from their African winter quarters in April,
they tend to establish territories in autumn-sown cereal fields.
During the early summer, winter-wheat crops shoot from 20 cm up
to at least 70 cm in just a few short weeks. Pairs that are already
nesting in cereal fields will stay there until the chicks fledge
but any birds looking to establish new nests will prefer to switch
to non-cereal crops, including peas, field beans and potatoes, the
last being by far the most preferred crop. The loose canopy of a
potato field appears to be ideal habitat, providing easy access
to the ground as well as allowing adequate concealment of nests.”
Overall breeding success in the study was relatively low, with
59% of attempts failing completely. Ground nesters suffer predation
by mammal and birds. In this study, rates of predation were highest
in field beans, where nests were often poorly concealed. With low
rates of chick production, the recovery of the Yellow Wagtail is
heavily dependent on the number of broods that can be attempted
in a single season. At the current level of productivity, and given
that most second broods seem to only occur in potatoes, the availability
of this crop could determine the fate of this species.
James Gilroy concludes that, “Yellow Wagtail is currently
amber listed as a bird of conservation concern. Given that there
has been a marked decline since the 1980s, potato crops could be
crucial to the future breeding.”
You can help track the arrival of Yellow Wagtails this
spring, and other migrants such as Swallows and Cuckoos, by contributing
to the BTO/RSPB/BirdWatch Ireland BirdTrack survey. For more information
on how you can get involved visit
www.birdtrack.net
Please see over for Notes for Editors
Notes for Editors
- James Gilroy’s PhD work at the University of East Anglia
was funded by Natural England, RSPB, BTO and Anglian Water.
- BTO News is the British Trust for Ornithology’s
newsletter, keeping members informed about the latest results
from surveys and topical issues concerning birds and the environment.
It is published six times a year (at two-monthly intervals).
- BirdTrack is an online bird recording scheme
www.birdtrack.net organised
by BTO on behalf of BTO, RSPB and BirdWatch Ireland. Click on
the 'Register for BirdTrack' link. Registering is free.
- Table of crop preferences

- Photographs of Yellow Wagtails are available.
Contact
for electronic versions. Please quote 2008/03/11
- The BTO has an ISDN line available for radio interviews.
For further information please contact:
Graham Appleton on 01842 750050 or e-mail:
(during office hours)
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