RACING PIGEONS â IMPACT OF RAPTOR PREDATION

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also died between the time of the ring being issued and the CSL questionnaire being sent. A total of 117 fanciers confirmed that the rings recovered belonged to birds released during the 2002 season. The equates to 1.98 pigeons per eyrie searched. However, the range varied from 0-10 (Figure 5.3). A correction factor can be applied to take into account pigeons whose details were not returned to CSL. This is based on the proportion of birds from each of the years 1997-2001 which were known to have been lost in 2002. If this is done, the figure rises to 144 pigeons, which equates to 2.44 pigeons per eyrie. Number of eyries 30 25 20 15 10 5 0 0 1 2 3 4 5 6 7 8 9 10 Number of confirmed 2002 kills Figure 5.3. Number of confirmed kills of Scottish racing pigeons per eyrie (2002) An additional factor which must be taken into account is that some rings were missed on the original searches. A total of six sites were subject to re-searches with a view to assessing the possible level of rings not recovered on a first visit. The mean period between the original search and the re-search was between 17 and 18 weeks (range four to 23 weeks). Two of the sites were recently-closed quarries where no additional rings were found. The remaining four were natural sites where varying number of additional rings were recovered on the second search. There appear to be a number of reasons for this. One is that the suppliers of the metal detectors used advise that the equipment is 5% more efficient when the soil is wet compared to when the soil is dry. Thus sites searched in dry conditions in the early autumn would be expected to produce some additional rings when re-searched in wet conditions. Two other factors to consider are that searching in winter when vegetation has died back should allow both better visual searches and more effective use of the detector, and that if a territory has continued to be occupied by peregrines between the original search and the re-search, pigeons may have been killed during the period between the two searches. The total number of rings recovered from the six re-searches was 193 (0, 0, 83, 81, 18 and 11 respectively) compared to 180 rings found on the original searches (Figure 5.4). It should be noted that recent rings made up a much lower proportion of the rings found on re-searches than was the case with the original searches, and relatively 54
few were from birds either confirmed as being lost in 2002 or which were potentially lost in that year. 25 Number of rings recovered 20 15 10 5 0 initial secondary 1920-1930 1941-1950 1961-1970 1981 1983 1985 1987 1989 Year(s) 1991 1993 1995 1997 1999 2001 Figure 5.4. Comparison of the number of rings recovered from eyries during initial and secondary searches. Using this information, a further correction factor can be applied to those sites where second searches were not carried out as it is highly likely that some rings from these sites were also not recovered on the first visit. Thus a total of 259 recent Scottish rings were found on sites with only one visit. On the second searches which were carried out, an additional 87.7% recent rings were found compared to the original search. Overall, 65.1% of the rings recovered originated in Scottish lofts, so second searches could be expected to lead to around 244 additional recent Scottish rings. Analysis of the flight history information provided by fanciers shows that 56% of the recent rings belonged to birds killed in 2002. Applying this factor to the possible 244 additional Scottish rings missed gives a figure of 137 pigeons. If this figure is added to the 144 birds known to have been killed or the rings of which were recovered but no flight history was provided, a total of 281 pigeons killed arises, or an average of 4.76 racing pigeons per eyrie. The eyries and nest sites searched during this study had varying degrees of breeding success during the 2002 season, ranging from four young successfully reared to territories held by non-breeding pairs. If it is assumed that these were representative of the situation nationally in 2002, the above results on minimum racing pigeon losses can be extrapolated nationally. Thus, with a peregrine population of 630 breeding pairs and 65 non-breeding pairs (see Table 5.6) within areas which will be used by Scottish racing pigeons to varying degrees, this suggests a minimum of 3,308 Scottish racing pigeons killed by peregrines. The 2002 peregrine census also identified 348 single birds either on or off territory. If it is assumed that each single peregrine takes 50% of the racing pigeons taken by a pair, this means that an additional 828 Scottish racing pigeons may be lost to single peregrines, giving a total minimum loss of 4,136 Scottish racing pigeons to peregrines. 55
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RACING PIGEONS - IMPACT OF RAPTOR P
Page 5 and 6:
CONTENTS PAGE 1. EXECUTIVE SUMMARY
Page 7:
6.3 DETERRENTS USED IN OTHER CIRCUM
Page 10 and 11:
OB=48). Collectively, however, the
Page 12 and 13: • The risk of sparrowhawk predati
Page 14 and 15: 1.5 REVIEW OF DETERRENTS • A revi
Page 16 and 17: • Overall reported losses to spar
Page 18 and 19: 2. INTRODUCTION 2.1 BACKGROUND Pere
Page 20 and 21: During the Second World War (1939-4
Page 22 and 23: Table 2.1. Changes in the peregrine
Page 24 and 25: website, 2002). In South Wales, Dix
Page 26 and 27: 2.5.2 Sparrowhawk Diet Sparrowhawk
Page 28 and 29: In 1996 a total of 34,685 birds fro
Page 30 and 31: Dixon (2002) also estimated the num
Page 32 and 33: more likely to follow natural featu
Page 34 and 35: 3. TOTAL REPORTED LOSSES FROM SCOTT
Page 36 and 37: 3.3a). The circumstances of losses
Page 38 and 39: Figure 3.2. Location of lofts used
Page 40 and 41: Table 3.3 Regional comparison of ol
Page 42 and 43: would be expected as a consequence
Page 44 and 45: p>0.05), although at the Federation
Page 46 and 47: Ayrshire Loft 25 20 15 10 5 0 1981
Page 48 and 49: 4. REPORTED LOSSES TO SPARROWHAWKS
Page 50 and 51: Table 4.1. Summary of reported loss
Page 52 and 53: Table 4.2. Comparison of reported l
Page 54 and 55: irds, a mean of 0.91 birds per loft
Page 56 and 57: 5. LOSSES TO PEREGRINES AWAY FROM L
Page 58 and 59: Figure 5.1. Regional distribution o
Page 60 and 61: crags were also examined unless it
Page 64 and 65: 5.2.3 Discussion It was always reco
Page 66 and 67: 5.4 ESTIMATE OF POTENTIAL STRAYS 5.
Page 68 and 69: Figure 5.5. Principal race routes f
Page 70 and 71: 5.4.3 Discussion The rate of potent
Page 72 and 73: These 86 questionnaire returns were
Page 74 and 75: Table 6.2. Frequency of multiple lo
Page 76 and 77: within the area of application. The
Page 78 and 79: Table 6.6. Management techniques wh
Page 80 and 81: 1986). Peregrines in Britain, likew
Page 82 and 83: pitched wail and may illuminate at
Page 84 and 85: development to ensure that the chem
Page 86 and 87: deterrents were regularly moved and
Page 88 and 89: located at another loft) and two un
Page 90 and 91: other stimuli. Essentially, the mor
Page 92 and 93: 7. FIELD TRIALS OF RACE DETERRENTS
Page 94 and 95: Table 7.1. Return rates of racing p
Page 96 and 97: 8. CONCLUSIONS AND RECOMMENDATIONS
Page 98 and 99: 9. FUTURE RESEARCH Accurate recordi
Page 100 and 101: Trials of loft-based deterrents The
Page 102 and 103: Conover, M.R. 1979. Response of bir
Page 104 and 105: Inglis, I.R. 1980. Visual bird scar
Page 106 and 107: Nicolaus, L.K., Herrera, J., Nicola
Page 108 and 109: Toyne, E.P. 1998. Breeding season d
Page 110 and 111: pigeons are available to peregrines
Page 112 and 113:
Daily Food Intake (DFI) Redpath & T
Page 114 and 115:
Reliability of the available data T
Page 116 and 117:
Estimates of potential peregrine ki
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