The Peregrine Falcon (Falco peregrinus) in Cumbria The Super Recovery: 1963 – 2012

Introduction

The Peregrine Falcon is the largest falcon in Britain and probably one of the most emotive birds on the British list.  This is the story of the decline and eventual recovery of the Peregrine Falcon in Cumbria.  It aims to highlight to problems the birds faced prior to the Second World War and those that manifested themselves after the war and illustrate the measures taken to monitor the population as well as protect and conserve the few birds that were left after the disastrous pesticide era in the 1950s and 60s.

[airesizeimg src=”http://raptorpolitics.org.uk/wp-content/uploads/2013/10/Sam-Peregrine-09.jpg” alt=”Sam-Peregrine-09″ class=”aligncenter size-full wp-image-12494″ ]

Image courtesy of Sam Hobson

They have been very heavily persecuted over the past century in all areas of Britain and especially in Cumbria.  It is a bird that is loved or hated by many different people.  Legitimate falconers love it for its great power and speed because it is the most suitable bird for falconry purposes. Egg collectors love it for the beautiful large eggs that are laid.  To any collector a clutch of Peregrine eggs is the highlight of his collection.  Birdwatchers love it for its sheer beauty and the dexterity of the birds and the fact they inhabit beautiful mountainous country.  On the other hand gamekeepers hate it because they claim they take and kill grouse on the moors and they shoot or poison any birds that stray or attempt to breed anywhere near the moors.  In addition racing pigeon fanciers also hate them, claiming they attack and kill birds during races.  They deliberately go out of their way to destroy eggs and chicks in their nests and poison adults at their nest sites.

The area covered by this paper is the new county of Cumbria, which includes the old counties of Cumberland, Westmorland, Lancashire North of the Sands and part of north Yorkshire. This is the area described by and referred to by the Reverend H A MacPherson as the Faunal Area of Lakeland in 1892.  Historically the traditional nesting crags were in central Lakeland and on fairly remote land at around the 500 metre (1600 feet) and usually high crags with lots of alternative nest ledges. These are regarded as first class crags with precipitous faces 60m high.

[airesizeimg src=”http://raptorpolitics.org.uk/wp-content/uploads/2013/10/Falcon-Crag-Borrowdale.jpg” alt=”Falcon-Crag-Borrowdale” class=”aligncenter size-full wp-image-12521″ ]

Falcon Crag Borrowdale, Image courtesy of Geoff Horne

During the 1930s, Cumbria had a relatively stable population of 41 pairs at regularly occupied sites, but egg collectors systematically worked all these traditional sites and stole not only the first clutches of eggs, but also repeat clutches.  This robbery is probably the main reason why the population did not increase during this period. However the 41 pairs occupying traditional sites is the benchmark figure of 100%, on which to all future population studies are based.

The main decline in the population occurred in the 1950’s and early 1960’s, when Dr Derek Ratcliffe, who was at that time deputy director of The Nature Conservancy Council (NCC) observed females breaking and eating there eggs.  By 1956 he felt that there was something going very peculiar was afoot and there was something unexplained happening to the birds. In 1960 homing pigeon fanciers from Wales petitioned the government to remove legal protection from falcons in some districts.  The British Trust for Ornithology (BTO) was asked by the NCC to organise a study of the distribution, districts and food of Peregrines in Britain.   They invited Derek to organise their enquiry. The enquiry was spread over two seasons 1961-1962, but it was soon apparent in 1961 that there was a dramatic decline in all areas of the United Kingdom.  In Cumbria the 1939 population of 41 pairs had crashed to only 6 pairs by 1963, a decline of 85%.  Following restrictions on the use of pesticides introduced in1962, 1964 and 1966 signs of a recovery were noticed by 1967.  Increases from such a low level were believed to have involved movement of birds into Cumbria from other areas, such as the Scottish Highlands, where the effect of pesticides was less severe.

[airesizeimg src=”http://raptorpolitics.org.uk/wp-content/uploads/2013/10/peregrine-copulating-279S.jpg” alt=”peregrine-copulating-279S” class=”aligncenter size-full wp-image-12496″ ]

Image courtesy of Terry Pickford

Methods and results

In order to carry out the survey a large number of volunteer peregrine enthusiasts were approached to check every known peregrine site in their particular area of interest at least twice and preferably three times during the breeding season.  The first visit would in late March or early April to establish if the site was occupied, the second visit would then be in late April to see if eggs had been laid and a final visit would be in the middle of June to check for any signs of chicks being raised.  The intention was to carry out the survey nationally every ten years in order to monitor any trends in the further decline or recovery of the population.  In Cumbria the local enthusiasts decided to attempt to carry out the monitoring of the local population every year.

In 1971 national Peregrine survey revealed 21 pairs occupying territories in Cumbria.  This perceptible recovery continued and by 1976 the number of territories occupied was up to 43, this exceeded the 1939 baseline figure of 41.  At this stage it was felt that things were back to normal and the population would stabilize itself at this level.  Over the following years the number of occupied sites continued to increase at a steady rate of on average 3.5 new pairs per annum.  By the next national Peregrine survey in 1981 the Cumbrian population had reached 59 pairs an increase of 144% set against the national population total which showed an increase of 90%.  With this increase in numbers it was obvious that new second class territories were being established.  These tended to be centred on smaller, less remote crags, as well as in both working and abandoned quarries.

This unprecedented increase also coincided with an increased interest in pigeon racing throughout the UK.  The effect in Lakeland was that every Saturday morning throughout the racing season, April to September, thousands of homing pigeons were flying north, south, east and west through the county, making pigeons a relatively easy source of prey. With the number of pigeon rings issued by the Royal Pigeon Racing Association being over 1.5 million in 1971 and between 2 and 2.5 million in 1991 the number taken by Peregrines in Lakeland would be minimal and would have no detrimental effect on the overall numbers of pigeons flying through the county. It is estimated that the annual number of pigeons lost to Peregrines would be around 3.5% of the total but the real figure is likely to be appreciably lower and would mainly consist of tired birds, stragglers or those that have become feral.

[airesizeimg src=”http://raptorpolitics.org.uk/wp-content/uploads/2013/10/4-Peregrine-Chicks-United-U1.jpg” alt=”4-Peregrine-Chicks-United-U” class=”aligncenter size-full wp-image-12497″ ]

Image courtesy of Terry Pickford

This exceptional rate of recovery carried on through the 1980’s and by 1991 the year of the next national survey the Cumbrian population had increased to 95 pairs or 232%.  Again this unprecedented increase in the recovery continued by on average 3.5 new pairs per annum, until it peaked in 1997 and 1998 at 100 pairs.  This was an increase of 244% on the base line 1939 number of 41 pairs.  With this unprecedented increase in occupied sites, it was inevitable that in the 1980’s and 90’s the author, with help of Bob Buchanan of Dalston and John Davidson of Cockermouth, was inspecting between 50 and 55 sites annually with at least two or three visits to each.  The increase also meant that with the population at this level, birds were struggling to find nesting sites and had to resort to third class sites such as small riverside crags and broken rocky outcrops.

In order to monitor the breeding behaviour of the birds and check what was happening to both eggs and chicks it was essential to go down onto the nest ledge and examine the nest contents thoroughly.  Often the only way of finding out if the birds had laid eggs or broken and eaten the contents was to climb up the crag or abseil down on to the nest ledge.  Very few of the ledges could be accessed easily and some involved crags that were 60 meters high.  On these high crags the procedure was to knock a steel pin into the ground at the top of the crag, tie the 60 meter rope to it, put on the climbing harness, then clip the cloggy descender and the safety shunt to the rope and abseil down the crag to the nest ledge.  This is a very dangerous operation which requires very careful consideration of every manoeuvre, making sure at all times that no rocks or lumps the turf are knocked off the face of crag onto the nest scrape.  Whilst this is going on the adult birds were invariably calling furiously and generally showing their displeasure by diving at the intruder at high speed in mock attack to show their disapproval at this intrusion into their nest space.

[airesizeimg src=”http://raptorpolitics.org.uk/wp-content/uploads/2013/10/Peregrine-Sentinal.jpg” alt=”Peregrine-Sentinal” class=”aligncenter size-full wp-image-12498″ ]

Female Cumbrian Peregrine: Image courtesy of Terry Pickford

The other main reason for this intense crag work was to secretly and openly mark any eggs to deter egg collectors and also to secretly mark any chicks which could potentially be stolen.  Just as the population was starting to recover the stealing of eggs and young, which had been a feature of the 1930’s started again in the early 1970’s.  Egg collectors came from all areas of the north of England to steal eggs for their own collections and to sell them on to other collectors, including some American collectors.  Chick thieves came from the north east of England to steal chicks for falconry purposes.  The chicks were first sold to a falconer in the south of England for approximately three to four hundred pounds each, the price depending on the sex of the each young bird, females were more valuable than males and commanded the higher price.  They were then smuggled out of the country into Germany to a falconer who paid between eight hundred and a thousand pounds for them.  Peregrines are the preferred bird for falconers and in great demand by rich Arabs in the Middle East who were prepared to pay thousands of pounds for a fully manned female peregrine. It has been claimed that the selling price by the German falconer was fifteen thousand pounds. This illustrates why the villains were prepared to take so many risks on the crags to steal chicks.  One even lost his life in the process of stealing eggs.

[airesizeimg src=”http://raptorpolitics.org.uk/wp-content/uploads/2013/10/Peregrine-eggs.jpg” alt=”Peregrine-eggs” class=”aligncenter size-full wp-image-12504″ ]

4 Red Peregrine Eggs: Ground nest near Shap: Image courtesy of Terry Pickford

In order to combat this high level persecution at a time when the Peregrine population was starting to recover a number of concerned individuals started to camp out under crags to deter would be thieves.  Other groups of people came together to protect specific sites, the classic one was at Falcon Crag in Borrowdale.  This site had a long history of persecution going back to Victorian times and throughout the early twentieth century.  The site became deserted in the 1950’s during the toxic chemical era.  It was not until 1974 that a new pair reoccupied the territory, but they were immature and did not breed. In 1975 this pair raised 3 young to fledging, but in the following four years the site became desert again with only occasional sighting of unattached birds.  The site was again occupied by a pair in1978, eggs were laid and the chicks that hatched were stolen when they were three weeks old by the gang from North Tyneside.  In the following three years eggs were laid and disappeared during incubation.  It is believed they were again stolen by the North Tyneside gang who were passing the eggs on to a falconer to hatch them in an incubator.   In 1982 members of the Keswick Natural History Society, together with members of Cumbria Wildlife Trust were made aware of what was happening by the author and they were persuaded to set up a daylight guard. Most of the ladies involved could only mount a daytime guard between 6.00am and 9.00pm and this resulted in three chicks being stolen, very early one morning in early June, at three weeks old.  Over eighty five people were involved in the watch, they were naturally very upset and were determined that the theft of “their” eggs or chicks would never happen again.

[airesizeimg src=”http://raptorpolitics.org.uk/wp-content/uploads/2013/08/PEREGRINE-SHOT-NEAR-bOLTON.jpg” alt=”PEREGRINE-SHOT-NEAR-bOLTON” class=”aligncenter size-full wp-image-12114″ ]

Tiercel Cumbrian Peregrine: Image courtesy of Terry Pickford

To that end they arranged a twenty four hour guard the following year 1983 with the help of the Keswick Mountain Rescue Team who agreed to sleep out overnight below the crag.  That year, four young falcons were raised to fledging.  With the guard continuing four young were raised each year for the following three years.  The only failure during the watch years was in 1987 when the eggs failed to hatch due to a hailstorm which caused the nest ledge to become waterlogged.  Naturally the watchers were delighted with the success of the watch and carried it on until 1993.   In that time 31 young had been raised, giving an average brood size of 2.8 young.  The Falcon Crag birds have continued to raise young in most years since the watch petered out and it is now the most productive site in Cumbria, raising 67 young over a 23 year period, giving a remarkable average brood size of 2.91 young.

The next national Peregrine survey which should have taken place in 2001 was cancelled due to an outbreak of foot and mouth decease in sheep and cattle throughout the region and access to the fells was stopped completely until the end of June when the Peregrine breeding season was almost finished.  The survey was rescheduled for 2002. It revealed a reduction in the number of pairs occupying territory from 100 in 1998 to 92.  This reduction in numbers, whilst being disappointing shows that the population was still 224% higher than the 1939 total and therefore not really a cause for concern.

Ringing

As part of the monitoring scheme qualified licensed ringers were encouraged to ring as many chicks as possible.  The reason for this was to find out where the birds went too after fledging, how far they had travelled, how old they were when recovered and where possibly the circumstances of their recovery such as were they sick and in care or dead.

Over a 42 year period the author was responsible for the ringing of 1347 chicks, of these 1157 were ringed by him personally and a further 190 by Terry Pickford using the authors rings.  When ringing the chicks at two to three weeks old it is possible to sex them by the difference in their size. In total 1083 were sexed of these 52% were male and 48% female.  Another feature of the ringing recoveries as shown in the life table is that 41% of the young birds die in their first year and a further 17% die in their second year. The recoveries also showed that 14 males lived to more than ten years old as opposed to females where only 3 have been recovered at over ten years of age. Peregrines are named for their propensity to wander and females were found to be the long distant wanderer’s with fourteen birds being recovered over 100 kilometres from their birth crag.  Male birds tend to be much more sedentary with only 6 moving more than 100 kilometres.

[airesizeimg src=”http://raptorpolitics.org.uk/wp-content/uploads/2013/10/Raven-Crag-Thirlmere..jpg” alt=”Raven-Crag-Thirlmere.” class=”aligncenter size-full wp-image-12522″ ]

Raven Crag-Thirlmere Valley, Image courtesy of Geoff Horne

Two recoveries of special interest were both males.  One ringed in June 1984 by Terry Pickford was picked up 17 years and 3 months later covered in mud. It was taken into care where it was cleaned up and released back into the wild a week later.  This bird held the national longevity record until another male that the author had ringed in early June 1994 with a BTO ring and a PIT ring (Passive integrated transponder ring) which contained a microchip, had the PIT ring read as a breeding bird at a nest site near Lochmaben in Dumfriesshire. The ring was first read in April 2009 when the bird was 14 years old and read again in May 2012, at the same site, making it 17 years 11 months old and thus breaking the earlier longevity record. This adult remained in the territory for the remainder of the breeding season and this would take it well over 18 years of age.

The future

It will be interesting to see if the next national Peregrine survey, which is expected that will take place in 2014 will reveal any further decline.  Preliminary results from the 2013 monitoring in Cumbria has revealed a decline in the number of occupied sites to an estimate of 75 pairs which is 25% of the 1998 peak figure of 100 pairs. This again is attributable the shortage of suitable prey during the breeding season and the incidence of very poor spring weather over recent years.

In some areas of the county  Peregrines are still continuing to experience heavy persecution, particularly in the west of the county where homing pigeon fanciers systematically destroy eggs and chicks as well as poisoning adults near their nest sites.  In the east of the county, on the north Pennines, birds are routinely killed by gamekeepers and grouse moor managers who take every opportunity to shoot and destroy not only Peregrines, but Hen Harriers, as well. If this level of persecution persists as it is at present there will inevitably be a further decline in those areas.

Over the years there have been a number of proposals to strengthen the legislation protecting wildlife throughout the UK and in 2000 the Wildlife and Countryside Act, 1981 was amended by the Countryside and Rights of Way Act, 2000.  These amendments gave the police and courts greater powers to tackle wildlife crime.  The possibility of a fine up to £5000 or to imprisonment for up to six months or both became a huge deterrent to would be thieves this has reduced the incidence of egg collecting and chick stealing in the core breeding areas for Peregrines in central Lakeland to a much lower level.

[airesizeimg src=”http://raptorpolitics.org.uk/wp-content/uploads/2013/10/Peregrine-Prelude-to-copula.jpg” alt=”Peregrine-Prelude-to-copula” class=”aligncenter size-full wp-image-12501″ ]

Female Peregrine: Prelude to copulation: Image courtesy of Terry Pickford

Another worrying event that happened in 2000 was the publication of the UK Raptor Groups Report to Ministers.  One of the aims of the Working Group was to examine the effects of raptor attacks on racing pigeons and recommend ways of reducing the numbers taken as prey.  The main recommendation to the pigeon fanciers was to train their birds to fly round the county rather than flying through it.  This recommendation was taken up by them and they trained their birds to fly up new race routes in eastern England and along the west coast of Cumbria.  The net result of this action has been that in 2002 the amount of prey available to the falcons was dramatically reduced.  Instead of the thousands of pigeons flying through the county on a Saturday morning there was only a trickle, this meant that the birds were deprived of sufficient prey until the middle of May when young Rooks flocked onto the fells for the hatch of the craneflies, (Tipulidae). Inevitably the reduction in food supply at the critical time when chicks were hatching resulted in smaller brood sizes.

An even bigger problem for the falcons has come as a result of climate change.  The very cold wet weather in late winter and early spring invariably left the breeding females out of condition resulting in late egg laying dates.  The heavy frosts and extremely cold wet weather we have experienced at the end of April and up to the second week in May during the first part of this century has caused eggs to be chilled and fail to hatch as well as newly hatched chicks to die of hypothermia.  This again has contributed to smaller brood sizes and much lower productivity that has been found over the last ten years.

[airesizeimg src=”http://raptorpolitics.org.uk/wp-content/uploads/2012/12/Peregrine-food-pass-picture.jpg” alt=”Peregrine-food-pass-picture” class=”aligncenter size-full wp-image-10318″ ]

Image courtesy of Sam Hobson

Conclusions

The term “super-recovery” was first used by Derek Ratcliffe in 2002 and showed that with the elimination of pesticides and a more readily availability supply of a clean food the population could recover to unprecedented levels.  In addition, targeted protection of the birds together with a more enlightened interest by members of the public in what was happening in the natural environment has undoubtedly helped with the Peregrine recovery.  At the peak of the recovery in1998 the Peregrine density in Cumbria was believed to be one of the highest in the world. Another plus is that from ringing returns it is obvious that Cumbrian birds have been instrumental in the re-colonisation of many parts of England and Scotland.   However the perceived and worrying decline in the Cumbrian peregrine population over the past 15 years is a cause for concern and hopefully is not indicative of the start of long term decline.

Acknowledgements:

My indebtedness to Ernest Blezard, Robby Brown, Teasdale Stephenson and Ray Laidler for their friendship, guidance and encouragement in my fieldwork during the 1960’s and 1970’s is immeasurable. I shall always be grateful and consider it a privilege to have known them and being able to learn so much from their vast store of knowledge of natural history. I am most grateful to Derek Ratcliffe for all his help,  encouragement and guidance. His companionship in the field is much appreciated, as is that of two stalwart friends John Davidson and Bob Buchanan who were always there to encourage and assist when needed.   I wish to record my gratitude to Colin Armitstead, Geoff Fryer, and Derek Hayward, together with Terry Pickford, Paul Stott and Paul Marsden of the North West Raptor Group for generously and freely sharing the results of their work for other areas of the county. Much help has also been received from RSPB staff at Haweswater and Geltsdale over many years especially John Day, Dave Shackleton, Malcolm Stott, Stephan Ross and Dave Walker. Many friends and associates throughout the north of England have been generous with their help, especially the following; Robert Aylmore, David Anderson, Ian Armstrong, Dorothy Blezard, John Callion, Mike Carrier, Peter Davies, Martin Davison, Ian Findlay, Adrian George, Robin Griffiths, John Hamer, Neil Henderson, Steve Hewitt, Ken Hindmarsh, Dorothy and Stewart lllis, David Jardine, Tony and John Laidler, Brian Little, Dave Mark, Paul Martin, Stephen Martin, Mike McGrady John Miles, Mick Mills, Steve Petty, Jean Scott, George Smith, Les Steadman and Terry Wells and Tullie house for designing the maps. Finally, I am most grateful to David Clarke for all the help and assistance he has given in the compilation of this paper and formatting the charts.

Geoff Horne

October 2013

Breeding performance of Peregrine Falcons in Cumbria 1966 -2012

Data gathered from fieldwork by the writer and co-workers

                                    1966  1967  1968  1969  1970  1971  1972  1972  1974  1975

Known territories *          41      41      41      41      41      41      41      41      42      42

Territories examined        25      25      28      27      25      35      15      16      17      22

Occupied territories           8       13     15      19      19       21       9         9      10      18

Pairs rearing young           2         7       7       11       7       10        2        6         4      10

Young reared                    4       18      13      21      15      28        3       16       11      22

Mean brood size           2.00   2.57   1.86   1.91   2.14   2.80   1.50    2.67    2.75   2.20

Mean young per pair    0.50   1.38   0.87   1.11   0.79   1.33    0.33   1.78    1.10   1.22

 

                                     1976  1977  1978  1979  1980   1981  1982  1983  1984  1985

Known territories             42      48      50      56      61       68      75      79      85      92

Territories examined        33      43      45      50      57       63      71      72      81      84

Occupied territories          27     37      37      43       50      59      67       68      75      77

Pairs rearing young            9      18      21      19       27      23      44      37      44      39

Young reared                    22      42      51      43      72      50    121       81    113     89

Mean brood size            2.44   2.33   2.43   2.37   2.67   2.17   2.75    2.19   2.57  2.28

Mean young per pair     0.82   1.14   1.38   1.05   1.44    0.85   1.81   1.19   1.51   1.16

 

                                     1986  1987  1988  1989  1990  1991  1992  1993  1994  1995

Known territories             94      94      97      99    101    107    108    115    120    121

Territories examined        82      73      90     79      90     105    104    111    112    116

Occupied territories          82     73      82     73      79       95       97      94      98      94

Pairs rearing young          39     38       47     43      44       64      53      41      62      57

Young reared                    88     95    110    106    116    153    125      85    148    150

Mean brood size           2.26   2.50   2.34   2.47   2.64   2.39   2.36   2.07   2.39    2.63

Mean young per pair    1.07   1.30   1.34   1.45   1.47   1.61   1.29   0.90    1.51   1.60

                                        1996  1997  1998  1999  2000  2001  2002  2003  2004  2005

Known territories              124    129    131    134    135    135    137    140    140   141

Territories examined         119    122    122     115   117      64    125     118    123  118

Occupied territories             87    100    100       89     83       45      92       90     81    78

Pairs rearing young              42      68      57       37     46       28      31      37     58    44

Young reared                      118   156    136        86   111      63     64      81    142   100

Mean brood size                2.80  2.29   2.39    2.32   2.41   2.25  2.06   2.19  2.45   2.27

Mean young per pair         1.36  1.56    1.40   0.97   1.34       –    0.70   0.96  1.75   1.28

 

                                                  2006  2007  2008  2009  2010  2011  2012

Known Territories                      142    142    142    142    143    143    143

Territories examined                   120    117    103    106    120      98    112

Territories occupied                      88      79       58      58      70      57     63

Pairs rearing young                       57      46       33      31      54      37      28

Young reared                             127    103       77      64      80      77      66

Mean brood size                        2.23   2.24   2.39   2.06   1.95   2.08   2.35

Mean young per pair                 1.44   1.30   1.32   1.21   1.14   1.35   1.05

 

Mean brood size is number of young reared per number of pairs rearing young.

Mean young per pair is number of young reared of known breeding sites.

* ie,  the historically accumulated total of known breeding sites.

 

 

 

 

 

 

 

 

 

 

1 comment to The Peregrine Falcon (Falco peregrinus) in Cumbria The Super Recovery: 1963 – 2012

  • It’s always a joy to see and hear peregrines when we are out and about. I didn’t know that so many good souls were involved in the monitoring and protection of the species here. Thanks so much to all for the efforts made to sustain and monitor these beautiful birds. The photographs in the article capture the birds so well, and without doubt it is a story well told by someone with obvious passion and dedication. Without people like you Geoff, the world would be a much poorer place.