White-tailed Eagle

White-tailed Eagle
White-tailed Eagle (A. Challis)

Annual monitoring data

Please click on the links below to access summary data. These summaries are based on SRMS regions.  Descriptions of some of the main headings reported against are provided here.

2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022

National & regional trends

Our latest analysis of SRMS White-tailed Eagle data for the period 2009-2018 has produced national trends in breeding number and productivity at a national level , as well as for four of the seven SRMS regions  and four of the 14 NHZ regions for which the SRMS holds White-tailed Eagle records.

Please see below for a more detailed account for this species. To find out more about the trends analysis and the various products we have been able to produce please visit the Trends pages.

White-tailed Eagle trends 2009-2018

A previous analysis covering the period up to and including 2015 produced national and regional trends which can be viewed below. Please click on the links within the tables below to view the graphed trend of interest.

White-tailed Eagle national population trends:

ParameterPeriodYearsMean annual sample + SEType of trendMean + SE
Breeding pairs1983-201533NA*Exponential increase27.4 ± 4.4
Laying success1995-20152138.3 ± 5.2Linear increase0.9 ± 0.0
Clutch size1983-20153320.5 ± 2.9Stable1.5 ± 0.0
Hatching success1995-20152136.7 ± 4.6Linear increase0.7 ± 0.2
Brood size1995-20152124.0 ± 3.3Stable1.5 ± 0.0
Fledging success1985-20153124.6 ± 3.9Linear increase0.6 ± 0.0
Number of fledglings1995-20152120.8 ± 3.3Stable1.4 ± 0.0

*No annual sample was calculated, because we were not dealing with a sample of breeding pairs, as we had full knowledge of every pair. Therefore, we give the mean annual number of pairs in the column “Mean ± SE”.

White-tailed Eagle regional population trends based on SRMS regions:

SRMS RegionBreeding parameterPeriodYearsMean annual sample + SETrendMean + SE
ArgyllBreeding pairs1998 - 201518N/A*Linear increase13.3 ± 1.9
ArgyllClutch size1998-2014179.7 ± 1.1Stable1.6 ± 0.0
ArgyllHatching success2007 - 2015917.6 ± 1.9Stable0.8 ± 0.0
ArgyllBrood size2000 - 2015169.9 ± 1.2Stable1.4 ± 0.4
ArgyllFledging success1998 - 20151811.8 ± 1.7Linear increase0.7 ± 0.0
ArgyllNumber of fledglings2005 - 20151111.5 ± 1.4Stable1.3 ± 0.0
HighlandBreeding pairs1987 - 201529NA*Linear increase14.3 ± 1.8
HighlandClutch size1990 - 20152611.8 ± 1.3Stable1.4 ± 0.0
HighlandHatching success1996 - 20152017.1 ± 1.5Stable0.7 ± 0.0
HighlandBrood size1995 - 20152110.2 ± 1.2Stable1.5 ± 0.0
HighlandFledging success1994 - 20152214.6 ± 1.5Stable0.6 ± 0.0
HighlandNumber of fledglings1998 - 2015189.3 ± 1.0Stable1.4 ± 0.0
Lewis & HarrisBreeding pairs2004 - 201512NA*Linear increase9.4 ± 1.2
Lewis & HarrisClutch size2005 - 2015118.6 ± 1.2Stable1.5 ± 0.1
Lewis & HarrisHatching success2006 - 20151010.2 ± 1.4Stable0.6 ± 0.1
Lewis & HarrisBrood size2005 - 2015116.1 ± 0.9Stable1.6 ± 0.1
Lewis & HarrisFledging success2008 - 201589.3 ± 1.3Linear increase0.6 ± 0.1
Lewis & HarrisNumber of fledglings2007 - 201595.6 ± 1.0Stable1.6 ± 0.1
UistBreeding pairsN/A**
UistClutch sizeN/A**
UistHatching successN/A**
UistBrood sizeN/A**
UistFledging successN/A**
UistNumber of fledglingsN/A**

*No annual sample was calculated, because we were not dealing with a sample of breeding pairs, as we had full knowledge of every pair. Therefore, we give the mean annual number of pairs in the column “Mean ± SE”.
**Sample size too small for meaningful trend production.

White-tailed Eagle regional population trends based on Natural Heritage Zones:

NHZBreeding parameterPeriodYearsMean annual sample size + SEType of trendMean + SE
3. Coll, Tiree & the Western IslesBreeding pairs2000 - 201516N/A*Linear increase11.4 + 1.7
3. Coll, Tiree & the Western IslesClutch size2002 - 2015149.9 ± 1.2Stable1.5 ± 0.1
3. Coll, Tiree & the Western IslesHatching success2006 - 20151014.4 ± 1.6Linear increase0.7 ± 0.0
3. Coll, Tiree & the Western IslesBrood size2004 - 2015128.7 ± 1.0Stable1.6 ± 0.1
3. Coll, Tiree & the Western IslesFledging success2008 - 2015814.1 ± 1.6Linear increase0.7 ± 0.0
3. Coll, Tiree & the Western IslesNumber of fledglings2006 - 2015108.7 ± 1.2Stable1.5 ± 0.1
4. North West SeaboardBreeding pairs2008 - 20158N/A*Stable5.4 ± 0.4
4. North West SeaboardClutch size2005 - 2015113.6 ± 0.3Stable1.6 ± 0.1
4. North West SeaboardHatching successN/A**
4. North West SeaboardBrood sizeN/A**
4. North West SeaboardFledging success2012 - 201544.8 ± 0.5Stable0.7 ± 0.1
4. North West SeaboardNumber of fledglingsN/A**
6. Western SeaboardBreeding pairs1986 - 201530N/A*Linear increase17.2 ± 2.0
6. Western SeaboardClutch size1986 - 20153012.9 ± 1.3Stable1.5 ± 0.0
6. Western SeaboardHatching success1995 - 20152120.8 ± 1.6Stable0.7 ± 0.0
6. Western SeaboardBrood size1991 - 20152511.9 ± 1.3Stable1.5 ± 0.0
6. Western SeaboardFledging success1987 - 20152915.3 ± 1.7Stable0.6 ± 0.0
6. Western SeaboardNumber of fledglings1995 - 20152111.4 ± 1.4Stable1.4 ± 0.0
8. Western HighlandsBreeding pairs2010 - 20156N/A*Stable4.3 ± 0.3
8. Western HighlandsClutch size
8. Western HighlandsHatching success
8. Western HighlandsBrood size
8. Western HighlandsFledging success
8. Western HighlandsNumber of fledglings
14. Argyll West & IslandsBreeding pairs2010 - 20156N/A*Linear increase5.5 ± 1.1
14. Argyll West & IslandsClutch size
14. Argyll West & IslandsHatching success
14. Argyll West & IslandsBrood size
14. Argyll West & IslandsFledging success
14. Argyll West & IslandsNumber of fledglings

*No annual sample was calculated, because we were not dealing with a sample of breeding pairs, as we had full knowledge of every pair. Therefore, we give the mean annual number of pairs in the column “Mean ± SE”.
**Sample size too small for meaningful trend production.