1996 RAPTOR ROUND UP
Produced by the
Scottish Ornithologists’ Club
on behalf of all
Scottish Raptor Study Groups
with grant aid from
Scottish Natural Heritage

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Supplement to Scottish Birds Volume 19 1997
ISSN 0036 9144

Introduction

Welcome to the second issue of the new format Raptor Round Up. This is produced by
the Scottish Ornithologists’ Club on behalf of the Scottish Raptor Study Groups with
grant aid from Scottish Natural Heritage.

Raptors enjoy an increasingly prominent place in the politics of the Scottish countryside.
The high productivity of the still tiny Red Kite population and the (now) healthy Hen
Harrier population at Langholm show just how much potential Scottish environments
still have for robust raptor populations. Against this potential must be set the continuing
criminal interference that many raptor species still endure with a Hen Harrier situation
that must be counted a national disgrace. Scottish Raptor Study Groups are privileged
to be in a unique position amongst such bodies by being represented on the
government’s working group on birds of prey where Patrick Stirling-Aird gives eloquent
voice to the Groups’ views and concerns. It is yet to be seen how the recent change of
government will affect these matters.

In 1996, as ever, seasonal weather patterns imposed their local and regional effects on
overall raptor breeding performance and must sometimes mask long term trends.
Peregrines continue to maintain a healthy and expanding population overall with poorer
performance in the north and west; Sea Eagles are slowly building up their breeding
population but probably depend on continued introductions for long term viability; Red
Kites show every sign that they should be acommon bird throughout most of the country
if given the chance; Buzzards continue their welcome return to the eastern lowlands;
Ospreys continue their slow but steady expansion despite a renewed increase in egg
collecting. Other birds, such as the Hen Harrier, have bleak immediate prospects
although we now know how quickly they might recover if given the chance; and itis easy
to be complacent about our “stable” Golden Eagle population and forget the gaping
holes in parts of its breeding range which cannot always be explained by the state of
the habitat.

The Scottish Raptor Groups continue to play an important part in measuring the state
of these birds. This report describes some of this work.

Keith Morton
This report was written by Sylvia Laing and Keith Morton and edited by Keith

Morton and Stan da Prato. The Scottish Raptor Study Group logo was
designed and drawn by Keith Brockie.

1996 Raptor Round Up

Osprey

Known Prs Prs
prs eggs hatched
104 93 76

One hundred and four nest were known to
be occupied by pairs in 1996, which is 5
more than in 1995. Two other traditional
eyries had single birds present for at least
short periods and several other sites were
visited for single days. Five further pairs
were seen but their nests were not located
or they did not breed; to keep records
comparable over the years, these are not
included in the official total. It is now
getting difficult to locate every pair each
spring.

Eggs were late in 93 nests which is only
one more than last year. There were further
problems with egg stealing; 4, possibly 5,
clutches were illegally taken by egg
thieves, including a clutch of 4 eggs. In
this context, it was disappointing that the
Scandinavian ringed female, which was
robbed last year, did not return to breed.
Thirteen nests failed with eggs, including
a pair in Tayside which were shot out.
Several nest failures were due to very
strong winds in May.

Two pairs failed with chicks but 74 pairs,
one more than last year, reared a total of
155 young, and a further 8 young were
translocated from northern Scotland to
England. The overall production of young
from the known Scottish population was
1.49 young per nest occupied by a pair
and 1.66 young per pair laying eggs,
which is better than 1995. The mean
brood size of successful nests was 2.09.

1
Broods Young Production
successful fledged young/prs
74 155 1.49
Tayside In Tayside, from 33 sites

checked, 28 pairs laid eggs and 24 were
known to hatch and fledge a minimum of
49 young, 41 of which were ringed.

Two fewer sites were occupied than 1995
but it was a more successful year overall.
Only one pair was known to definitely
have been robbed. A second pair may
have been robbed or may have failed
naturally - they relaid and reared one
chick. One nest was blown out and a
second pylon nesting site was discovered.
A 1993 Perthshire bred chick was found
dead with shotgun pellets near New
Lanark. The male at Loch of the Lowes
was a 1991 Loch Garten chick. Other
evidence of movement of individuals
between the various Scottish populations
included a 1990 Aberdeenshire bred
female nesting near Crieff and a female
bred in 1993 in north Perthshire nesting in
Ross-shire.

Osprey Derek Robertson

2 1996 Raptor Round Up

White-tailed Eagle

There were 12 pairs or trios holding territory in 1996 (10 in 1995). There were no other
adult birds occupying any of the known areas, and the number of breeding birds (or birds
capable of breeding) on territory remained the same as 1995 at 26.

The birds in the new territory found last year successfully produced a chick this year.
The Scottish bred pair bred again and were finally successful. This raises the number
of known successful pairs of Sea Eagle in Scotland from 6 last year to 8 in 1996.

A record 12 clutches were known to have been laid, compared with 9 in 1995 anda
record 8 clutches hatched. Seven broods survived to fledging, which was also the
highest to date, and 9 young fledged, again the best year yet. Overall, therefore, 1996
was an excellent year.

Seven year summary

1990 1991 1992 1993 1994 1995 1996

No of pairs or trios 9 9 8 8 10 10 12
No of unpaired birds

on territory 3 1 2 4 1 4 0
No of birds onterritory 21 20 19 21 22 26 26
No of areas occupied 12 10 10 10 11 14 14
No of clutches laid 9 8 9 6 8 9 12
No of clutches hatched 2 4 4 4 4 6 8
No of broods fledged 2 4 4 4 4 5 a
No of young fledged 2 7 7 5 5 7 9
Cumulative no of territories

producing young 4 4 5 5 5 6 8

A further 10 birds were brought in from Norway as part of the ongoing release
programme. All were successfully released.

eae he

White-tailed Eagles talon grappling John Love

1996 Raptor Round Up

Red Kite

Red Kites

Seventeen breeding pairs produced a total
of 39 young during the 1996 breeding
season, the most successful so far.
Moreover, it was remarkable for other
reasons:

1 Allthe 15 pairs (30 adults) which bred
in 1995 survived to breed again in 1996.
All individuals, with the exception of one
pair, remained faithful to each other.

2 There were 11 successful nests in
1995 and 8 of these nests were reused in
1996. However, none of the 4 nests which
failed in 1995 were reused in 1996. This

Andrew Stevenson

trait has
implications for the growing population. It
suggests that in successive years
successful breeding pairs are both nest
and mate faithful, whilst unsuccessful pairs
move to new sites and may change mates.

important conservation

Clutch and brood size

Clutch size was established for 12 nests.
When the broods were about 4 weeks old,
all known nest trees were climbed and the
young weighed, ringed and wing tagged.
In addition a ‘blood’ feather in pin was
removed from the under wing coverts of
each chick for DNA sexing at Nottingham
University.

Red Kite breeding success in 1996

Number of occupied territories 22
Numbers of pairs which laid eggs We
Mean clutch size (from 12 nests) 3.20
Numbers of nests which fledged young 16
Mean number of young per successful pair 2.44
Mean number of young per pair which laid eggs 2.29
% of pairs which fledged young 94%

4

Hen Harrier

Territories
occupied
Perthshire 32
Angus 1
Argyll & Bute 34
North East 15
Lothian & Borders 1

(E Sutherland/E Ross)
Predominantly un-keepered 9

(Strathspey/Moray)

Predominantly grouse moor 10
Dumfries & Galloway 22
South Strathclyde 37

Perthshire Although some persecution
took place the main failure was due to
poor weather in May. Forty five young is
only 50% of the production of the early
90’s. The brood size appeared quite high,
but the failure rate was recorded as very
high. In Angus, a single pair failed at the
egg stage.

Argyll and Bute A total of 34 nests
were monitored in Argyll & Bute. Of these
nests 24 (71%) were successful and
fledged a total of 83 young. Overall
productivity was 2.44 young per laying
pair, which was slightly above the long
term mean. The Argyll and Bute summary
includes information from the RSPB Loch
Gruinart reserve which held 9 females on
territory. Seven nests were located and
fledged a total of 18 young. One site in
Mid Argyll failed at the large chick stage
and persecution is strongly suspected.
On Islay, uncontrolled muir burn affected
a number of nesting localities.

1996 Raptor Round Up

Territories Minimum Number of
knownto noofyoung young per
have fledged fledged successful
young territory
45
24 83 3.45
5+ 12+
1 4
7 25 3.6
6 15 2.5
11 36
15 55+ 1.48
North East Birds numbers and

productivity in Deeside and Donside were
very low with only 3 pairs on site in lower
Deeside, 2 of which fledged an unknown
number of young. The number of young
fledged is unknown from the 3, possibly 4
pairs known or suspected in mid Deeside.
No young fledged from the 4 pairs found
in Donside. In Moray, 4 out of 5 pairs laid
eggs and 12 young fledged from 3 nests,
all these nests being on grouse moor. No
birds were reported in the Cabrach area.
Overall this shows a downwardtrend since
1989 with persecution suspected as the
main cause.

Lothian & Borders One pair fledged
a minimum of 4 young in the Moorfoots.
The outcome from one or 2 other pairs in
the Moorfoots and one pair in the
Lammermuirs is unknown.

Highland Breeding success in 1996
followed avery similar pattern to previous

1996 Raptor Round Up

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Hen Harrier

years with productivity and nesting
success highest on the northern,
unmanaged moors of Sutherland and
Easter Ross, and lowest on the managed
grouse moors in the south and east (see
table). The combined total of 19 nests
produced 13 broods and 40 fledged young
(mean 3.1 young/successful nest and 2.1
young/nest found).

Dumfries & Galloway Again there
was no proved breeding in the Stewartry
area although birds were seen in late April
which perhaps still had time to breed in
what was a very late season for this
species. Good breeding success was
enjoyed by those pairs which were allowed
to, but there has been a worrying increase
in human interference in some areas with
- as is typically the case -_ insufficient
evidence for any prosecutions to be
brought.

South Strathclyde Thirty seven
occupied territories were located in the 4
main breeding areas of North Ayrshire &
Renfrewshire, east Ayrshire, south Lanark
and south Ayrshire. Laying commenced
at the normal time, earliest first egg 23
April, latest 13 June, with the bulk of
clutches being started in the first fortnight
in May. Eleven full first clutches were
recorded averaging 5.1 eggs, with only
one clutch of 6, slightly down on last year

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Mike Ashley
with 2 x 6’s and one 7. From 9 nests 93%
of eggs hatched. If not interfered with,
survival rate of broods were high; 90% of
young hatched fledged successfully, there
being only one natural failure due to Fox
predation. Once again this year the main
cause of failure was human interference,
which was known or strongly suspected in
18 failed attempts. In addition, 2 nests
suffered brood reductions, with chicks
being removed prior to fledging. Ata
further 2 sites the females were shot and
the males left to rear the young - in both
instances successfully. This may have
affected the long term survival prospects

of these fledglings.

Recorded prey items were mostly Meadow
Pipits and Skylarks, with grouse starting
to feature later in the breeding cycle. At
one nest in south Ayrshire the 20+ day old
chicks were fed the haunch of a three
quarter grown Rabbit. Vole numbers were
high in parts of east Ayrshire and would
have been important in early spring.

Only 2 tagged birds bred in the area this
year - both females - one a 1992 bird from
Wigtownshire, another a 1993 bird tagged
in the southwest and found breeding in
south Lanarkshire. The one ringing return
was from a female found dead at a nest in
Upper Nithsdale. She had been one of a
brood of 4 ringed in 1994 in south Ayrshire.

6 1996 Raptor Round Up

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Goshawk Ayrshire Bird Report 1991

Goshawk
Territories Territories Territories Minimum Number of
checked occupied knownto noof young young per

have fledged fledged successful
young territory
Tayside 1 4 4
Lothian & Borders 18 10 11 22 2

Lothian & Borders AlthoughGoshawk _ found after hatching produced 13 young.
numbers are slowly increasing, siteshave Eight sites failed due to persecution,
still to be found in Lothian. Of the nests probable persecution, disturbance and
found at the egg stage, 22 young were __ natural failures. No failures were reported
produced from 24 eggs. Another4 nests from nest robberies.

1996 Raptor Round Up

Buzzard
Territories Territories
checked occupied
Argyll 99
Lothian & Borders 52 52
Highland 83 81
Argyll The RSPB reserve at Loch

Gruinart had 3 pairs hunting over it, all of
which nested successfully and reared a
total of 5 young. On Coll, 13 nesting pairs
were located and many fledged young
were seen but individual nesting success
and productivity was not collected in 1996.
The Rabbit population on the island is still
at a very high level. On Colonsay &
Oronsay at least 21 pairs were present
and at least 13 nests produced young. At
8 nests where the nest contents were
visible, 15 young were reared. On the
Cowal 21 pairs reared 21 chicks in the
Loch Eck - Glen Branter study area.
Elsewhere in the Cowal, 36 sites were
located and, of these, 26 successful sites
fledged at least one chick. In mid Argyll 5
successful pars were monitored and
reared 8 chicks.

Lothian & Borders Of the 52 sites
occupied only 12 were not confirmed as
breeding (but most probably were). Of
the 40 sites where eggs were laid, only 2
failed, one due to the loss of large young
(possible robbery) and the other failed to
hatch possibly due to bad weather (this
was a ground nesting site).

7
Territories Minimum Number of
known to noofyoung young per
have fledged fledged successful

young territory
75+
38 102 2.68
67 135 1.6

Highland For the second year running
a brood of 5 was raised in Easter Ross.
Overall, however, it was another merely
average breeding season. In the main
Easter Ross study area, 54 pairs were
carefully followed. Two pairs did not lay,
13 failed at the egg/small chick stage and
one failed with medium chicks when the
nest was blown out in a gale. Average
brood size from successful birds was 2.1,
but, due to the 30% of pairs that failed,
only 1.6 young were fledged per territorial
pair. This study area, like many other iow
lying parts of the eastern Highlands, has
seen an increase in the number of breeding
pairs (up from 40 pairs in 1994). This is
partly due to colonisation of new areas
(probably linked to a decrease in
persecution) and also to in-filling in areas
with dense Rabbit populations. In one of
these areas (Nigg Ferry) 11 pairs now
nest in an area 4x2km with nests only
550m apart on average. One nest
contained a clutch of 6 eggs. This was
possibly due to 2 females laying in the
same nestas only 2 young were eventually
reared. The high density and the large
number of ‘new’ pairs may be partly
responsible for the high failure rate of
some of these birds.

8

Golden Eagle

Territories Territories
checked occupied
Central Scotland 10 9
Tayside WofA9 15 15
Tayside E of A9 12 10
Argyll 57 54
North East 18 8
Highland 99
Lewis & Harris 7 7
Uists 18 10

The Golden Eagles that did breed in
Tayside in 1996 experienced a high
rate of success, including one territory
which was successful for the first time
since the 1970’s. This bird nested on an
artificial platform in a ‘quiet’ part of its
home range. Overall productivity,
however, in relation to the potential number
of pairs, continues to be very low, with the
majority of ranges containing single
immatures/juveniles, or remaining
apparently ‘empty’ for the last 15 years.
Recent information gathered by RSPB
suggests a higher level of egg collecting
has been taking place than previously
realised. West of the AQ, it was a very
poor year.

Improved coverage in North Argyll
meantthat 57 home ranges were checked.
Birds were present in all but 3 and at least
37 clutches were laid. Twenty five
successful nests fledged 29 young
including a brood of 2 from atree site (rare
in Argyll). These figures indicate an
improved breeding season. However,
results could have been better had human

1996 Raptor Round Up

Territories Minimum Number of
knownto noof young young per
have fledged fledged successful
young territory

3 3 1

5 6+ 1.2+

4 6 1.5

25 29

6 7

36 44 1.22

2 2 1.0

6 7 1.17

interference at sites on Mull not resulted
in failure at the egg stage of 3 nests.
These matters were the subject of a
successful prosectution.

North East A poor season mainly due
to weather in the early part of the year.
Eighteen pairs were located of which 8
laid eggs, 7 hatched and a total 7 young
fledged from 6 nests. An upper Deeside
pair has disappeared.

A substantial number (99) of pairs of
Golden Eagles were checked for breeding
success throughout Highland Region
in 1996. There was a healthy distribution
of records from across the Region,
although appreciably more pairs were
monitored in the west and southwest than
inthe north and east. Information for many
pairs was patchy for the middle part of the
breeding season, notably for the nestling
period. So, asin previous years, the results
are presented to show ultimate breeding
success figures only.

In general, breeding success of 0.44 chicks
per pair was below the longterm average

1996 Raptor Round Up

9

of around0.5 chicks per pair. Performance
was especially poor in mainland areas in
the western half of the region, with an
exceptionally poor success rate of 0.14
chicks per pair in south Lochaber. Better
breeding performance occurredin the east
and in Skye, both of which are areas

Golden Eagle with Manx Shearwater

where natural food supply in summer is
more abundant than in the west mainland.
The high success rate among the small
number of pairs from the Small Isles was
particularly encouraging and somewhat
unexpected. Rum, in particular, had its
best Golden Eagle breeding success for
many years.

John Love

10
Peregrine

Territories Territories

checked occupied

Central Scotland 40 30
Tayside
Perthshire W of A931 25
Perthshire Eof AQ 17 16
Angus 36 31
Argyll 23 13
Lothian & Borders 55 52
Highland 40 33
S Strathclyde
coastal 6
inland 11
Dumfries & Galloway
coastal 26
inland 54
Uists 15 8
North East
inland grouse moor 44 27
inland non-g moor 37 et
coastal 16 11

Tayside East of the A9 quite a good
season was noted. A female bird ringed
at Loch Leven in 1989 as a nestling was
recovered dead from natural causes at its
nest site on the Lothian side of the Forth
rail bridge. One eyrie contained the
remains of a Gadwall and an adult Swift.
Angus also had a good year witha slightly
higher than usual success rate, although
eggs were removed from 2 sites. An
immature female laid 3 eggs at 2 different
sites, both unsuccessfully. In the second
case desertion occurred a few days before
the eggs were due to hatch.

Argyll Ofthe 23 sites checked 20 were
on the Cowal, 9 sites were not occupied

1996 Raptor Round Up

Territories Minimum Number of
known to noofyoung young per
have fledged fledged successful
young territory
22 43 1.95
10 20 2.0
14 37+ 2.64+
20 47 2.35
9 16
26 70 2.69
28 56 1.7
5 11/12
6 12
12 26/27
35 69
8 14+ 0.58+
6 17 2.83
WZ 38 2.24
8 17+ 2.13

and an additional 3 known sites were not
checked. The 8 successful sites fledged
at least 14 chicks and 3 sites failed.
Elsewhere in Argyll, few sites were
monitored but breeding was proved on
Coll, Colonsay (where 2 chicks were fed
extensively on Kittiwakes), Scarba
(outcome unknown) and Bute (failed). In
mid Argyll 3 sites were monitored; two
failed and one fledged 2 chicks. For
another successive year a pair acted
territorially in February-March atthe RSPB
Loch Gruinart reserve on Islay but no
breeding attempt ensued.

Lothian & Borders Of the 52 sites
occupied, 17 failed mainly due to human

1996 Raptor Round Up

Peregrine

Ayrshire Bird Report 1990

interference. Of these 17 pairs, 6 failed at
the egg stage, 4 pairs failed at the young
stage and 7 pairs failed due to the
disappearance of one or other of the adults.
A further 12 pairs failed due to natural
Causes.

Highland A total of 40 sites were
checked (4 less than in 1995). Thirty five
were occupied by pairs, but eggs were
laid at only 33 sites. Hatching occurred at
28 sites and at least 56 young were
assumed to have fledged from 26
successful nests.

17

Overall, Peregrines appear to have hada
good year, despite poor weather in early
spring, which probably resulted in some
pairs at higher altitudes failing to breed.
However, out of all the areas covered, this
was probably only evident in east
Inverness.

Productivity (young per territorial pair) in
1996 was 1.7 compared with 1.2 in 1995
(a below average year). This figure would
have very likely been higher if a nest had
not been robbed in east Sutherland. In
addition, itis likely that the actual numbers
of young fledging from some nests was
higher than the numbers recorded. On the
plus side, anew pair bred successfully on
the Black Isle, which constitutes the first
successful breeding for many years. Two
young were removed under licence for
use in a reintroduction project in eastern
Germany where it is hoped to establish a
tree nesting population.These were
excluded from productivity calculations.

South Strathclyde A productive year
despite significant human interference at
inland sites with a minimum of 0.82 chicks
fledged per occupied territory.

Dumfries & Galloway Another very
productive year with 1.19 chicks per
occupied territory, the best producitvity
rate in south Scotland.

North East Coastal birds did well
rearing 3 times as many young per
occupied site as in 1995 although fewer
sites were occupied. Inland birds breeding
away from grouse moors hada reasonable
year but pairs on grouse moors had yet
another poor season with only 0.63 young
fledged per occupied site (1.03 per
occupied site away from grouse moors).

12 1996 Raptor Round Up
Merlin
Territories Territories Territories Minimum Number of
checked occupied knownto noofyoung young per
have fledged fledged successful
young territory
Perthshire 46 26* 11 27 -
Angus 20 14** 9 (+17?) 27 3.0
Argyll & Bute 4 - - - -
North-East 38 33 28 >93
Lothian & Borders 53 34 6+
Highland 30 20 16 56 3.5
S Strathclyde 19 10 8 17+ 2.1
Dumfries & Galloway 14 9 8 24+ 3.0
* Includes 10 tree nests
** Includes 1 tree nest
In Perthshire fewer young were raised, North East In lower Deeside the

with several traditional sites not occupied.
Five pairs are known to have definitely
failed. The fate of another 10 pairs is
unknown.

In Angus the situation looked good up till
midJune. Theloss ofaclutch anda brood
and the depletion of young between ringing
and fledging spoilt the early high hopes.
Seven broods were colour ringed to a
specific year and site in Angus. One 1995
youngster was found dead in a crow trap.

Argyll & Bute Several regular sites
were apparently unoccupied in 1996 and
no successful sites were monitored in
1996 (Kintyre 1; Knapdale 1; Mid-Argyll 1;
Bute 1). A pair were again present on the
RSPB reserve at Loch Gruinart in May but
not thereafter. On Colonsay there were
several sightings and reports in the early
spring butno nesting attempt was located.
On the Cowal, a nest located at one usual
site contained broken eggshells and was
presumed predated.

population and overall breeding success
has remained fairly constant over recent
years. There has been no recent habitat
degradation, indeed improved heather
cover in upper Glen Dye has resulted in
the resumption of breeding by Merlins
there after an absence of several years.
Most of upper Deeside has a stable
population of birds but there has recently
been a reduction in the number of pairs
found in mid Deeside, particularly in Glen
Tanar.

In Donside, Banffshire and Moray local
populations were considered to be fairly
constant during the 80s. Recent years
have shown marked fluctuations in
numbers and subsequent breeding
success in these areas. In particular, 1995
was a very poor year which was largely
due to the cold spring weather. Population
decreases were noted in Donside around
1992 and, by 1995, the number of occupied
territories there had halved. This decline
was somewhat reversed in 1996 and could

1996 Raptor Round Up

have been a temporary set back rather
than the onset of a long term decline.
Detection and understanding of such
fluctuations is one of the most important
benefits of long term raptor monitoring.

Lothian & Borders Some areas had
only partial coverage in 1996 therefore
too much cannot read from the above
totals. Of the 34 occupied sites, 16 are
known to have laid eggs and 12 of these
are known to have contained young.
However, the total minimum no of young
fledged at 6+ is partly due to the fact that
most sites cannot be checked for fledging
due to a variety of circumstances.
Experience over the years would suggest
that most of the nests containing young of
aringable size do in fact fledge some or all
of the chicks. The above summary is for
the whole of the area roughly defined as
SE Scotland. Coverage was complete in
the Lammermuirs, good in the Moorfoots,
patchy south of the Tweed and poor in the
Pentlands.

Highland Merlins in the Highlands had
a better than average breeding season
despite a mixed bag of weather across
the different areas. In Moray, Nairn and
Strathspey the weather was mainly dry
and cold during the laying and incubation
period and dry and sunny with very little
rainfall during the fledging period. The
weather during these crucial periods
appeared to favour successful breeding
and productivity was the highest recorded
in these areas over a9 year period. Once
again Strathspey and Badenoch birds did
significantly better than those from other
study areas, perhaps reflecting habitat

quality.

Fifty four percent of sites in Moray and
Nairn were unoccupied during 1996. The

13

reason for this low occupancy appears
difficult to understand as no significant
habitat changes or drop in prey numbers
were noted. Further north in Sutherland,
the weather was cool and wet during the
laying and incubation period and only
improved significantly during the fledging
period in July. Site occupancy in this area
was relatively high at 72% but breeding
success was well below other areas,
perhaps reflecting the effects of the poor
weather. Fifteen pairs found on eggs over
the total area covered by the group gave
an average clutch size of 4.4. Breeding
success, measured by number of young
per pairlaying eggs, was 2.9. These figures
were the highest recorded over the 9 year
study period.

No unhatched eggs were found in any of
the successful nests in Moray, Nairn and
Strathspey, as has been the case in
previous years. Hopefully, the lack of
unhatched eggs may be related to the
drop in levels of harmful chemicals that
have been recorded in eggs taken for
analysis in recent years.

South Strathclyde Atleast 17 chicks
fledged from 8 successful nests in 16
occupied territories. Six nests were not
located and, at 7 of the known nests, the
final outcome was not recorded. It is.
therefore. likely that the figure of 1.1
chicks per occupied territory was
somewhathigherin reality. One nestfailed
naturally.

Dumfries & Galloway A minimum of
1.8 chicks fledged per occupied territory.
This was the output from the 8 nests
where the final outcome was discovered.
Four nests were not located and at 5
others no outcome was determined.

14
Kestrel
Territories Territories
checked occupied
Ayrshire study area 46 37
Argyll 17 17
Highland 28

Ayrshire study area’ From early
February till the end of the first week in
April the dry, sunny weather suited
Kestrels and birds were on territory early
with an occupancy rate of 80% compared
to 50% in 1995.

Laying was predominantly in April with
only 2 of 18 known dates of 1st eggs being
in May. Two hens laid on 1 April, the
earliest known laying date recorded.
Clutch sizes were very high with one of 7
and 10 of 6 eggs being recorded.
Twelve adults were trapped and the 10
hens’ weights averaged 281g, well up on
1995 and slightly up on 1994. Only one
retrap was recorded, a hen in the same
territory forthe third season in succession.
All 6 recorded failures occurred at the
clutch stage; 2 nests became waterlogged
during a spell of driven rain (one site only
8 feet off the ground); 2 nests had eggs
taken with human signs evident; one nest
failed when the male was killed and
plucked by a Goshawk (the hen then
disappeared); one failure was
undetermined.

Productivity was extremely high with 4.7
young being raised per successful nest
and 3.5 for all breeding attempts. Fifty
eight young were ringed. Only 2 ringing
recoveries were received, one bird being

1996 Raptor Round Up

Territories Minimum Number of
knownto noofyoung young per
have fledged fledged successful
young territory
er 4.7
9 34
24 -

found dead only 1 k from its natal site the
following March and one ringed in the
Carrick Forest in June 1995 recovered
dead at New Cumnock in February 1996.

Argyll Two successful pairs were
monitored in mid Argyll and reared a total
of 7 young. In the Cowal. 15 occupied
sites were located; 7 sites were followed
up and these fledged a total of 27 young.

1 MOS
, Pad
1/3; 4 \
Yi 4 Ln i
UB as Cavey x

Aa)
ay)
4Ma
aw
/

Kestrels Frances Godfrey

1996 Raptor Round Up

Highland Twenty eight sites had pairs
present this year, one pair down on last
year’s total. Mean clutch size at 5.1 was
0.3 lower than last year, as was mean
brood size, which was slightly lower at 4.6
compared with last year’s 4.7. Overall
productivity was down from 4.2 chicks per
™~,

iia

i
WiMtp

“SS

AD.

Raven
Raven

Territories Territories

checked occupied

Centra! Scotland 46 35
Tayside 56 39
Argyll 10

Central Scotland Minimum number of
fledged young is unknown but 10
successful pairs reared 26 young. The
outcome of the other 9 successful pairs is
unknown.

Tayside Twenty one pairs are thought
to have fledged at least 43 young. All
were crag or cliff sites, apart from one on
a hydro-electric dam. In Angus, 3 pairs
successfully reared an unknown number
of young.

\
—— Se

15

pair to 3.9 chicks per pair. Failures were
predictably at the egg and early chick
stage.

Most records came from Sutherland and
East Ross and 71% of records were from
nest boxes.

Andrew Dowell

Territories Minimum Number of
knownto noof young young per
have fledged fledged successful
young territory
19 26 -
21 43+ 2.0+

Argyli All 10 nests located were on Bute
and 2 of these failed, the outcome of the
others is uncertain.

North East Many sightings of pairs and
groups of up to 21 birds but still no
evidence of birds breeding the the area.

Lothian & Borders’ The only
information received concerns a_ few,
new nests sites reported in the southwest
of the region. The species is reported as
increasing.

16

1996 Raptor Round Up

The influence of habitat on the reproductive output of
Buzzards in the Highlands of Scotland

Dominic Sargent

Highland Raptor Study Group data on the proportion of different
habitat types present within a 1km radius of a sample of Highland
Buzzard nests, the altitudes of those nests and the number of young
fledged from them were analysed in order to investigate possible
interactions between the different variables.

The data covered the 1990-93 (inclusive)
breeding seasons and provided details
on various aspects of nest site location;
breeding success/failure; food items; and
habitat types within 1km radius of the
nest. The 1km distance was considered
suitable for present purposes as Buzzards
Buteo buteo have been observed to
generally remain within 1km of their nests
(Newton, Davis and Davis 1982 Journal
of Applied Ecology 18:681-706). There
were 6 broad habitat categories: farmland;
grassland; heather; coniferous forest;
broadleaves; and deer forest. Failed nests
were excluded from the study as they
were thought not to be a true
representation of the total number of
failures.

The study area, which was contained
within Highland Region, was divided into
east and west Highlands. The west
Highlands comprised of Lochaber, west
Inverness, Skye and Lochalsh, west
Sutherland and north west Sutherland.
East Sutherland, south central Sutherland,
east Ross-shire, Moray and eastInverness
constituted the east Highlands.

Altitude had no effect on reproductive
output, measured as the number of young

fledged per successful pair, for either west
or east coast Buzzards (Spearman,
r=0.157 west; r=0.177 east, p>o.05 in
both cases). The average number of young
fledged per successful pair was
significantly higher in east coast Buzzards
(x=2.2) as compared with west coast
Buzzards (x=1.8) (Mann-Whitney
W=1359.5, n=79, p<0.05), a result
consistent with the findings of Swann and
Etheridge (1995 Bird Study 42: 37-43)
and probably related to food supplies.

Spearman correlations were carried out
to test for relationships between the
number of young fledged per successful
pair and the proportion of different habitat
types within 1km of each corresponding
nest site. For both the west and east
Highlands there was no significant
correlation between the number of young
fledged per successful pair and the
proportion of any one habitat type within
1km of the nest site.

Combinations of 2 habitat types also did
not result in any positive correlations
between reproductive output and habitats.

Ratios of the extent of each habitat type
between east and west coasts revealed

1996 Raptor Round Up

that the east coast had nearly 6 times as
much farmland, and over 2.5 times as
much farmland + grassland as the west.
The west had 50 times as much deer
forest as the east coast. To test for

17

Birds 69:199-210; Austin 1992
unpublished PhD thesis, University of
Glasgow). In so far as the east coast had
much farmland and grassland (53.2% of
total habitat area) and the highest

Tables 1 and 2: Results of Spearman correlations for numbers of young fledged
per successful pair and the percentage of a given habitat type within 1km of the

nest site.

Table 1 West coast: n= 32, p>0.05 in all
cases.

Habitat ‘r value
grassland +0.067
farmland -0.133
woodland -0.067
grassland & farmland +0.013
grassland & deer forest +0.065
deer forest & plantation -0.051
broadleaves & heather +0.005

interactions in habitats and fledging
success between the east and west, a 2
way ANOVA was used. The ANOVA
revealed that there was no interaction
between the numbers of young fledged
(east and west) and the proportion of
grassland and farmland within 1km of the
nest (F=0.46 df.=3 p=0.710). A similar
situation pertained for deer forest and
heather (f=0.26 df =3 0.857). A principal
component analysis of the data also
showed no significant relationship
between the proportion of different habitat
types within 1km of a nest site and the
number of young fledged from that nest.

Farmland and upland, perennial grassland
have been shown to be particularly
productive (Picozzi and Weir 1974 British

Table 2 East coast: n= 28, p>0.05 in all
cases.

Habitat ‘r value
grassland -0.165
farmland +0.051
woodland -0.143
grassland & farmland -0.053
broadieaves & heather -0.025

reproductive output, and the west had
considerable amounts of deer forest and
plantation (62.4% of total habitat area)
and the lowest reproductive success, it
might be proposed that, at the ‘regional’
level, the predominant habitats of an area
were a factor influencing reproductive
output.

It might reasonably be assumed that, in
the Highlands, as in other areas, food
supply is a major determinant of
reproductive success (for example: Dare
1961 Unpublished PhD thesis, Exeter
University; Holdsworth 1971 British Birds
64: 412-420; Tubbs and Tubbs 1985
Biological Conservation 31: 41-65). This
being the case, it would appear from this
study that food supply does not correlate

18

with the habitat characteristics within 1km
of the nest site. This situation may be
explained by the lack of data concerning
true territory size and quality and the time
spent by Buzzards in using agiven habitat
type. Considerable variation in Buzzard
territory size is recorded (see Dare 1961
unpublished PhD thesis, Exeter University;
Halley 1993 Bird Study 40: 24-30; Sargent
1995 unpublished BSc. dissertation,
University of St Andrews). Futhermore,
the sampling assumes that a nest is
located in the centre of a ‘territory’ and
that the ‘territory’ is of regular shape (ie a
circle). In reality, this is most unlikely
Brown (1976 British Birds of Prey Collins,
London) suggest that Buzzards devote

1996 Raptor Round Up

particular attention to favourable areas,
but does notindicate what the vegetational
characteristics of such areas are.

Despite the limitations of the data, this
study suggests that, within the area 1km
from a nest, there is, in spatial terms, no
habitat type that exerts a measurable
influence over the productivity (measured
as the number of young fledged per
successful pair) of a Buzzard pair; and it
has also emphaised the ability of the
Buzzard to successfully utilise different
habitat types.

| wish to thank the Highland Raptor Study
Group for allowing me access to their
Buzzard breeding data.

Dominic Sargent, ‘Cruach Innse’, Roy Bridge, Inverness-shire PH31 4AJ.

Buzzard

Bobby Smith

1996 Raptor Round Up

Acknowledgements

This report has been compiled from data
received from the Scottish Raptor Study
Groups. Our main correspondents are
listed below, although the data was
gathered by a far wider group of
fieldworkers than it is possible to
acknowledge individually. Doubtless there
are those deserving of mention whom we
have omitted. For this we apologise.

South Strathclyde - Dick Roxburgh,
Gordon Riddle, Ricky Gladwell and Chris
Rollie.

North East - Jon Hardy, Robert Rae,
Graham Rebecca, lan Francis and Brian
Cosnette.

Tayside - Patrick Stirling-Aird, Keith
Brockie, Bruce Anderson, Wendy
Mattingley, Ron Downing, Bradley Yule
and Ron Lawie.

Dumfries & Galloway - Chris Rollie and
Ricky Gladwell.

Lothian & Borders - George Carse, Alan
Heavisides and George Smith.

Central - Patrick Stirling-Aird, Dave Dick
and Don MacCaskill

Argyll - Roger Broad, Mike Gregory and
Dave Anderson

Highland - Roy Dennis, Colin Crooke,
Brian Etheridge, Jeff Watson, Bob Swann
and Jim Craib

19

Police Wildlife Liaison Officers

Central

Chief Insp Derek Brown, Police HQ,
Randolphfield, Stirling FK8 2HD 01786
456000

Insp lan Cameron, Police HQ,
Randolphfield, Stirling FK8 2HD 01786
456000

Dumfries & Galloway

Sgt Graham Young, 44 High St, Annan
DG12 6AJ 01461 202813

Sgt J McColm, Stranraer Police Office,
Stranraer DG9 8EG 01776 702112

Fife

PC Ronnie Morris, Kirkcaldy Police Station,
St Brycedale Ave, Kirkcaldy KY1 1EV
01592 418700

PC Graeme Heddle, The Police Station, Sea
Rd, Methil KY8 3DE 01592 418900

PC Michael Lawrie, The Police Station,
Regents Way, Dalgety Bay KY11 5QY
01383 318900

PC Mike Ward, Police Station, Napier Rd,
Glenrothes KY6 1HN 01592 418600

PC Rab More, Police Station, Stenhouse St,
Cowdenbeath KY49DD 01393 318600
PC Chris Stones, Police Station, Holyrood
Pl, Dunfermline KY12 7PA 01383 318700
PC Tim O’Brien, Police Station, Carslogie
Rd, Cupar KY15 4HY 01334 418700

PC Gavin Rae, Police Station, 100 North St,
St Andrews KY169AE 01334 418900

Grampian

Insp John Sellar, Banchory Police Statin,
Banchory, Kincardine AB31 3RP 01330
822252

Sgt Roddy Maclinnes, as above

Lothian & Borders
Sgt Brian Robertson, Dunbar Police Office,

Dunbar, E Lothian EH22 3AX 01368
862718

20

Sgt Malcolm Henderson, G Division, Kelso
Police Station, Coalmarket,Kelso TD5 7AH
01573 223434

Northern

Sgt John Grierson, Police Station,
Aviemore PH22 1RH 01479 810222

PC Ronald Dempster, Alness Police
Station, Obsdale Rd Alness, Easter Ross
IV170TU 01349 882222

PC David Dawson, Police Station, St
Margaret's Hope, Orkney KW17 2TN 0185
683529

PC R Gollan, Police Station, Lerwick,
Shetland ZE1 OJUN 01856 831529

Sgt A Heath, Police Station, Bettyhill,
Caithness KW14 01641 521222

PC J Williamson, Police Station, Foyers,
Inverness IV1 2QU 01456 486222

PC C D Souter, Police Station, Strontian,
Lochaber, Highland 01967 402022

PC Steven Cowie, Police Station, Storno-
way, Western Isles 01851 702222

Strathclyde

PC Norman Stewart, Glasgow Airport
Police Office, St Andrew Dr, Paisley PA3
2ST 0141 848 4515

PC Ronnie Sewell, Police Station,
Garelochhead 01436 810222

Insp T Smith, Cumbernauld Police Station,
South Muirhead Rd.Cumbernauld G67 1AX
01236 736085

DC John McLatchie, Police Station, 27
Westport, Lanark ML1 9HD 01555 662455
Ext 316

Insp Willie Allan, 1 King St, Ayr KA8 OBU
01292 266966

Mbt,

Sow

Immature Golden Eagle

Le Gy:
Vii C5 gy Yin,

Mag

1996 Raptor Round Up

Tayside (West)

Insp Alan Stewart, Tayside Police HQ, PO
Box 59, West Bell St, Dundee DD1 9JU
01382 23200

PC Scott McKinlay, Kinross Police Station,
High St, Kinross KY13 7AW = 01577 863571
PC Robert Noble, Pitlochry Police Station,
14 Atholl Rd, Pitlochry PH16 5BX 01796
472222

PC Donald Campbell, Crieff Police Station,
King St, Crieff PH7 3HA 017654 652247
PC Graham Jack, Coupar Angus Police
Station, Blairgowrie Rd. Coupar Angus PH13
9AT 01828 627343

PC Richard McCorquodale, Perth Police
Station, Barrack St Perth PH1 5SF 01738
621141

PC Bruce Sime, Abernethy Police Station,
Main St, Abernethy PH2 01738 850222

Tayside (East)

PC John Robertson, Arbroath Police
Station, Gravesend, Arbroath DD11 1HT
01241 782222

PC Simon Pedgrift, as above

PC lan Hutchison, The Police Office,
Brechin, Tayside 01356 622222

PC Harvey Birse, Forfar Police Station,
West High St, Forfar DD8 1BP 01307
302200

PC Neil Coupar, Birkhill/Muirhead Police
Station, Liff Rd. Muirhead, Angus DD2 5QF
01382 580214

PC Dougal Ogilvie, Edzell Police Station,
Dunlappie Rd, Edzell Angus DD9 7UB
01356 648222

ae

gM

1 BE

Steven Brown

The Scottish Ornithologists’ Club was formed in 1936 to encourage all aspects of
ornithology in Scotland. It has local branches which meet in Aberdeen, Ayr, the
Borders, Dumfries, Dundee, Edinburgh, Glasgow, Inverness, New Galloway,
Orkney, St Andrews, Stirling, Stranraer and Thurso, each with its own programme
of field meetings and winter lectures. The Waterston Library at the Club’s headquar-
ters at 21 Regent Terrace, Edinburgh EH7 5BT is the most comprehensive ornitho-
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to Friday, O930hrs - 1630hrs but please phone beforehand). A selection of Scottish
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Two issues of Scottish Birds are published each year, in June and December.
Scottish Bird News is published quarterly in March, June, September and Decem-
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publishs the annual Raptor Round Up on behalf of the Scottish Raptor Study
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