V 14 No.4 - The Scottish Ornithologists' Club

192 A. Watson & R. Rae
S8 14 (4)
young were well feathered, but still retained
some down, and so were not fully grown
or fully fledged.
At the end of each area section in the
Results, the first figure (max.) is the largest
number of pairs seen in any year there since
1973, and the second (est.) the estimated
total number of pairs each year. The first
figures cannot be added to give a grand
total, as many are from different years. To
get the second figure, we took the first one,
estimated by eye on the map the approximate
area that it applied to, added by eye
any extra areas where Dotterel have been
seen in one or more years, and multiplied
according to the visually estimated area of
other suitable-looking ground. This was
necessarily rough, as few observations involved
complete searches of measured areas.
For these calculations we assumed that
Dotterel were present every year on every
hill where they have been seen even just
once. For example, an observer might see
a pair on Hill A in 1985 and a pair on nearby
Hill B in 1986, but might not search Hill
B in 1985 or Hill A in 1986; this would appear
in the Results as two pairs, but there
might be only one. On some hills which are
well known haunts, birds have been found
breeding on every late-summer visit by an
experienced observer. However, in most
cases in the east, and nearly all in the west
Highlands, the notes covered only one or
two visits per hill over many years. This
possible error will be overcome only if
observers go to a reasonably big sample of
hills in the same summer.
We assumed, as there was no evidence
for doing otherwise, that numbers on each
hill were fairly constant each year, as on
A. W. 's three study areas. However, these
study areas are all on good habitat, and may
export birds to less suitable ground.
Numbers on sites that may be marginal
possibly fluctuate more; perhaps such sites
may be colonised each year by a varying
overspill only after the better places are fully
occupied. A regional survey in one year
could not overcome this problem; several
years study of good and possibly marginal
nearby sites would be needed. If many sites
prove to be marginal, with few or no birds
in some years, our total will be too high.
However, it may be too low for other
reasons (see Habitat, below).
Distribution and numbers
The following notes refer to years since
Nethersole-Thompson's book (1973), except
for pre-1973 information that was not in the
book. We use "hill" to mean a separate,
distinct hill, not a subsidiary top or summit.
Above 3000 ft (914 m), it corresponds to the
term "Munro" , and below 3000 ft to other
lesser but separate hills as defined in
Scottish Mountaineering Club guides
(Donaldson, 1984).
Aberdeenshire-Banffshire, east of the
Caimgorms massif. Pairs have been seen on
eight hills. Young have been reared on three,
and nests found on two others. Max. 6, est.
10+ .
Aberdeenshire-Angus. Has bred on six
boundary hills between the Perth-Braemar
road and Kincardineshire, and on three hills
to the north, with 5-7 pairs annually on a
study area on part of one hill. On another
hill, an observer came across seven nests in
1979 . Found breeding on every late-summer
visit to six hills. Max. 32, est. 70 + .
Angus. Has bred on three hills between
Glen Isla and Glen Clova, on one between
Glen Cl ova and Glen Esk, and on one in
Glen Esk, and has been seen on two other
hills in Glen Esk. Max. 6, est. 10 + .
Kincardinesbire. Pairs have been seen
in June at four sites on three hills, an adult
in July at one of them, and an adult in early
August on a fourth hill. At 580 m on one
hill, 6-7 have been seen together in late Julyearly
August in several years back to the
early 194Os, and in July 1942 or 1943 a
gundog picked up a flightless chick. Max.
4, est. 5 +.
Aberdeenshire-Perth. Has bred on five
boundary hills from Inverness-shire to
Angus, and on three to the north, including
tops down to 750 m. Max. 13, est. 20+ .
North-east Pertbsbire. Has bred on