- unexpected migrants
pairs of one of my favourite ducks, the Shoveler, are breeding on
Islay this summer. The pure white chest of the handsome male aids
identification at a long distance, even without the colourful combination
of dark green head and neck and rich chestnut flanks and, of course,
the very heavy-looking head and broad, spatulate bill.
Before the 1990s,
the only breeding records from the island were probable ones in
1957 and again in 1970. Then, in 1992, soon after the RSPB had surrounded
a rushy field on their Loch Gruinart reserve with earth banks and
flooded it with shallow water, a pair settled and bred there, and
here they have continued to breed ever since, increasing to the
current 10 pairs or so, more than keeping pace with the increasing
area of flood on the reserve where there are now four embanked fields.
And as the population has increased, so the occasional pair has
also bred on shallow pools elsewhere on the island.
a very distinctive feeding technique, swimming on the surface with
their bill half-submerged (though sometimes with the whole head
and bill completely underwater) and held slightly open. Water flows
in at the front of the bill as they swim and then out again through
the sides. Comb-like lamellae along the length of both mandibles
trap any small seeds and invertebrates in the water and are periodically
swept up by the tongue and swallowed. Sometimes groups of birds,
up to 100 or more strong, gather into a dense pack and perform manoeuvres,
turning in synchrony. The paddling of all these birds together stirs
up the water and thus increases the amount of available food items.
are present on Islay all year, as they are through most of Britain.
This could lead anyone to think that they are sedentary birds, resident
in the same area throughout their lives. However, ringing has shown
that this is not at all the case. Britain's breeding Shovelers,
numbering between 1000 and 1500 pairs, are migrants, setting off
in the autumn for Spain, southern France and Italy. They are replaced
by Shovelers from Iceland, Scandinavia and Russia. There are only
70-80 pairs breeding in Iceland, but they all appear to winter in
Scotland, with perhaps a few in Ireland. The main European breeding
range is in Russia, from temperate latitudes north to the sub-arctic,
with a population numbering perhaps 80,000-90,000 pairs. The great
majority of these winter in continental Europe, but the British
wintering population hovers around the 10,000 level.
The two best
places in the country to see Shoveler in winter are Rutland Water
and the Ouse Washes, both have had counts recorded in the region
of 1000 birds. Other excellent sites include Abberton Reservoir
in Essex, the Somerset Levels and Loch Leven. Shovelers are not
restricted to fresh water, as both the Burry Inlet in south Wales
and the Swale Estuary in Kent are among the top ten sites in the
country. Come the spring, these birds leave for their Russian breeding
grounds leaving the wetlands free for our breeders returning from
their Mediterranean winter sojourn.
Ogilvie is a natural history writer and editor, formerly a research
scientist with the Wildfowl and Wetlands Trust, and resident
on the island of Islay since 1986. Until 1997, a member of the
'British Birds' editorial board and also one of the editorial
team which produced 'Birds of the Western Palearctic'.