BOWLAND EAGLE OWLS, 2012.
Following the failure of the first nesting attempt by Bowland's Eagle Owls ( their egg(s) were allegedly smashed following deliberate disturbance by humans on the weekend of 24/25th March ) we are delighted to announce the successful fledging of two owlets on the United Utilities Estate in 2012.
Although what was believed to be the usual resident pair were present in their territory at the beginning of the year we became concerned by the lack of calling or courtship behaviour after 6th January. However, we put this down to the horrendous weather during that month, plus the disturbance effect of a Pheasant shoot on the 1st February, which might well have caused the pair to move site for a while as this species is highly sensitive to disturbance at their breeding sites early in the season.
To our relief, on 3rd February, the pair was back at the regular site and for the rest of the month their behaviour became more familiar, strongly suggesting that egg laying was imminent. Alas, it was not to be, the last sighting of the old female being noted on the 26th February. By 2nd March it had become obvious that something had gone wrong, as all courtship and calling had ceased and only the male was present around his favourite song post. Sadly we have to report that once again the cause of the female's disappearance has to be placed firmly at the door of humans, for we found four apparent nesting scrapes in the area, which along with their appearance and certain incriminating evidence, which I'm afraid we must refrain from disclosing at this stage, strongly suggest they were man made.
On 8th March the male was found calling at a new site and , on 11th March, he was accompanied by what was easily recognizable as a new female by her exceptionally large size and dark russet brown colouration. She was found to be incubating a single egg and from then on wasn't disturbed.
All was well on 23th March but, unfortunately, this was not to last. On Sunday, 25th March it was reported to the RSPB Bowland Officer, Jude Lane, that two young men had called at a nearby farm ( why would they do this?) to report that they had just disturbed an adult Eagle Owl and had discovered a nest containing one smashed egg from which the yolk was "still wet, having sunk into the material of the nest scrape " (sic). They seemed oblivious to the fact that, if this was the case, it was probably their own disturbance which had almost certainly resulted in her smashing the egg as she hastily departed the scene! They later reported, in an anonymously written letter sent to Mrs Chrissie Harper, that they had been searching for nesting Eagle Owls for some days before finally locating and flushing the incubating female from her nest. They had apparently collected and sent to Mrs Harper a fragment of eggshell ( presumably leaving the main eggshell remains in the scrape? ) plus what they described as " an unusually thick matted aggregation of Eagle Owl feathers, many of them soiled" for analysis. They theorised that, since the feathers had not been found within the nest scrape itself, or at a nest site, there was a suggestion that one of the adults may have been killed, then removed. However, a big question mark hangs over the description of events. having been notified of the men's report on 26th March Jude lane requested Mick Demain, the seasonal warden, to investigate the site to see if he could find any evidence of what might have occurred. Mick found the nest scrape to be empty, as reported, but the nest itself to be dry with no sign of shell fragments or Eagle Owl feathers, though a few wisps of dry down clung to the nest's interior. In his opinion what had occurred was simply a straightforward egg theft. While we have our suspicions regarding the motive for this, we cannot at this stage prove our theory, so reluctantly it will have to remain as conjecture for the time being. Frankly we were appalled at this set back and assumed that this was the end of the Eagle Owl story for 2012 especially when visits throughout the following days failed to locate any sign of the pair. It was therefore with a great sense of relief that on 30th March the new dark female and a calling male ( probably the usual breeder ) were relocated at a new site, which for obvious reasons we do not intend to disclose.
Because we were anxious not to cause the pair any further disturbance which would cause this marvellous area to be deserted completely, it was not until 19th May that we were able to confirm that the birds had continued breeding despite the trauma of losing their first egg(s). On that date a lone owlet was found at the estimated age of c.3-4 weeks old, strongly suggesting this was the product of a replacement or continuation clutch ( not unknown in this species). Given the unfortunate events leading up to this discovery we trust everyone will understand our decision not to report the success until the owlet had fledged successfully and was to the best of our ability out of danger from undue disturbance. We are glad we took this precaution for there is even better news to relate. On 3rd August it was discovered that in fact two owlets had fledged successfully, the second one having gone un-noticed until now owing to the difficult terrain and particularly dense vegetation cover which is so prevalent this year. This means that since the first successful breeding in 2007, no less than 15 Eagle Owlets have fledged successfully on the United Utilities Estate, as follows;
2007 (3), 2008 (2), 2009 (1 ), 2010 (3 ), 2011 ( 4 ) and 2012 (2 ).
Most have been BTO ringed.
The World Owl Trust would like to place on record our appreciation of the landowners, United Utilities, the RSPB and its Area Managers and seasonal wardens ( Jude Lane and Mick Demain in 2012 ), Natural England, and , in particular, the two RSPB Voluntary Fieldworkers, Bill Hesketh and Bill Murphy. These two remarkable men ( both in their seventies ) are often on site well before pre-dawn and long into the night, frequently in seriously severe weather conditions which would deter much younger men. Without their dedication and vigilance we have little doubt that the Eagle Owl story in Bowland would be very different.
Written by Tony Warburton, MBE, Hon. President World Owl Trust and based on notes and other summarized information compiled by Bill Hesketh.
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