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Birding in Wharfedale:
Goosanders
One of the most attractive of the water birds
we find along the River Wharfe is the goosander. This diving duck
is a 'sawbill', i.e. it has a long bill with a serrated edge, which
helps it catch active fish and crustaceans. It is an elegant bird
where both sexes have attractive plumage, but it is also shy and
will avoid crowds, so it is always a pleasure to come on a pair
along a quiet stretch of the river. Unlike many of the birds in
our area, the goosander was once a rarity and the first recorded
case of breeding here was a red-letter day; it is now a bird everyone
likes to record, so that we get a lot of sightings each year.
The Goosander
The goosander occurs throughout Europe and North America (where
it is known as a common merganser), and in the Far East. In Eurasia,
it breeds throughout northern countries, particularly in Scandinavia,
and across to the Bering Sea. It migrates in winter to warmer countries,
mainly to inland lakes, gravel pits and broad rivers. The original
estimates for Europe of 150,000 in the 1980's are now considered
much too low. The first recorded breeding record in the UK was in
Scotland 1871 but, since then, there has been a major expansion
south. It is now found throughout most of England. There were 2700
breeding pairs in UK in the late '80's, up from 1250 pairs in 1975.
In Wharfedale, the goosander is a scarce breeder and a common winter
visitor.
The other common sawbill in the UK is the
red-breasted merganser. However, the two species tend to be separated
by habitat. Goosanders favour rivers and inland lakes. It doesn't
tend to feed on the bottom of rivers and so is tolerant of deep
waters and fast flowing streams. By comparison, the merganser favours
shallower salt water, i.e. tends to be found around the coast. The
merganser is therefore a scarce visitor to our area with, typically,
2 or 3 sightings per year .
Breeding
Communal courtship can occur anytime from December, but peaks in
late winter and spring. Females are gregarious and often search
for suitable nest sites together. They usually nest near water -
in a hole in a tree, in a bank or in crevices amongst rocks; they
also frequently use nest boxes. The earliest eggs are laid between
the end March and early April; but usually from mid-April to early
May. There is 1 brood/year typically with a clutch of 8 to 12 eggs.
Incubation takes 30 to 32 days. Chicks leave the nest after couple
of days and are taken to the water, where they are cared for by
the female for 5 weeks. Meanwhile the male will desert the female
during incubation, and sometimes after the eggs are laid - only
rarely are male and female seen with young.
Goosander Movements and Habits
The migratory habits are complicated and unique amongst UK birds.
The almost complete disappearance of males during the summer remained
a mystery for many years. It is now known that males leave females
in late June and migrate to fjords of Northern Norway to moult.
They remain there until the advent of freezing, with early arrivals
in North Sea countries in late October and early November, but with
no large numbers until December, later than any other wintering
ducks. Females moult but stay in this country, along with a few
males. The goosander is a gregarious bird outside breeding season,
and large flocks gather during the winter when birds return to the
UK. In the summer groups of females can be found together.
The goosander locates food from the surface
with head under water and then dives expertly, using only its legs
for propulsion under water. It is particularly keen on eels and
salmon, which makes it unpopular with anglers. In fact the spread
of birds in recent years has led to them being regarded as an economically
important pest and it is now subject to licensed culling (see table
discussed below)
Birds are silent except during breeding when
the male croaks and the female cackles, although their wings can
make a whistling sound.
Finding goosanders in the WNS area
The following table summarises the trends in goosander population
in our area: the map shows sightings in the first half of this year.
You have a good chance of seeing goosanders
any time over the next six months. Your best hope is at Lindley
Wood reservoir, although views from the bridge can be distant and
you really need a telescope. Alternatively, try wandering along
one of the quieter reaches of the Wharfe. My own favourite spot
is the small, tucked away hide 400 yards north of the Cavendish
Pavilion on the west bank of the river. The riverbed there falls
quite rapidly and the water sparkles as it ripples over the rocks.
It's a quiet spot, with areas not easily seen from the nearby, busy
public paths, and I often see a pair of birds there. Alternatively,
it's a good spot for dipper and grey wagtails - or common sandpipers
in the breeding season.
John Flood
18/09/03
Goosander in the WNS area: An Historical
Perspective
Pre-WNS
Main sites for wintering birds in Yorkshire have traditionally been
Eccup Reservoir, Stocks Reservoir and Hornsea Mere (although with
little evidence of their presence before 1920), so they must have
been seen occasionally in our area.[For instance, 176 birds were
present on Eccup in 1979 when conditions were particularly severe
in Western Europe, and 118 were recorded on the Wharfe between Poole
and Arthington that same year when the reservoir froze over!]
1940's Generally 2 or 3 sightings a year in Washburn or to
the East - usually of 2 or 3 birds, although with 15 near Weeton
in March 1947.
1950's Little change, with 3 years when there were no sightings.
Most of sightings were on the Washburn Reservoirs at Swinsty and
Lindley - where birds appear to have been present for much of the
first 3 months of 1953. There was 1 record on the Wharfe at Ben
Rhydding in 1953, whilst birds were twice recorded at Grimwith Reservoir.
1960's
Numbers were, if anything, slightly down in the first half of the
decade. Significant increases from 1968, but with birds still being
seen mainly on reservoirs. Birds started appearing at Knotford Nook
in 1965, and were beginning to show a strong preference for Chelker
Reservoir from 1968 (when 31 were recorded at the end of that year).
Birds were winter visitors, starting to arrive in November and not
being recorded after March.
1970's
Not much change throughout the first half of the decade, although
the observation period extended to the first and last quarters of
each year. Regular sightings on the River Wharfe started to appear
in 1975. Chelker still a favourite, although good numbers on Lower
Barden Reservoir from 1977.A key event in 1976 was the first breeding
record at Bolton Abbey when large numbers watched a female and 8
young in June. At the time this was the most southerly record. Breeding
has occurred in the area almost every year since then, although
none was reported in 1989. (Breeding had been spreading southwards
since the first record in Scotland 1871. Birds bred in Northumberland
in '40's, on the River Tees in 1969, and in Wensleydale at Leyburn
in 1972.)
1980's - to present
Since then the goosander has become a common winter visitor and
a scarce breeding resident, with limited numbers of birds present
throughout the year. They are seen along the length of the river
and on the reservoirs, with those in Washburn and, in particular,
Lindley favoured by winter migrants since the early '90's. It seems
that breeding continues to be restricted to the river and there
has still been no records of breeding in the Washburn (so that sightings
there tend to be restricted to between October and May). There are
several reports of young each year, with a peak of 22 pairs with
young in 1997.The increase in numbers has not been universally welcome
and there was an application to cull birds from the fishing community
in 1994. In the last few years, and after a peak in the late '90's,
there has been a distinct decline in numbers with peak numbers,
presumably due to culling. Numbers on Lindley Reservoir have fallen
from a peak of 65 in 1999 to less than 30 in subsequent years (and
the peak so far in 2003 has been only 14). In 2002, there were actually
more young reported in Airedale than in Wharfedale!
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