Sunday 20 February 2011

Wknd 19-20 February

Main priority this week was BTO Atlas as the end of the final winter period approaches, just a week to go. Did the TTV off Reed Point, btwn Dunglass and Pease bay in Borders, not a great deal on the sea and just 86 Gannets passed south during the hour.

Sunday roved around a few inland areas, failing to find Oystercatchers in NT46 or any more duck at Markle. The taiga Bean remained at Waughton (seated, as it often has been, and I presume it is unwell), with 43 Mute Swans still in cereal east of Whitekirk.

More successful at dusk - Tawny Owl calling 17:35hrs in the north-east corner of Binning Wood - conveniently (for once) just inside the tetrad boundary (NT68A), thus a much-needed 10km tick! Shortly afterwards another was hooting from The Avenue, towards Tyninghame House, this one heard by the kids who were very excited. Both birds called shortly after I had done "cupped hand" hooting in attempt to provoke a response, but whether there is any connection I tend to doubt.

Better was too come as we took the backroads home and came across a beautiful Barn Owl perched up on the straight btwn Old Stonelaws and Redside (on the Whitekirk to Waughton Road). Bird then proceeded to hover over verge still in headlights before drifting off south; also a tetrad tick, NT58Q.

Also this week have had 5 post mortems back, the most interesting being that for the Barn Owl casualty at Old Craighall, recovered off a freshly dead Feral Pigeon (blog post of 7 Dec). Analysis confirms the owl was feeding on the pigeon, thus a very rare case of taking carrion, but also that the pigeon had probably already been scavenged by something else. However, the owl (a young male) was also deemed to be in very poor condition with no fat reserves and advanced muscle atrophy. This was also consistent with the low weight (280g) and lack of any ingested food before the pigeon. Thus the primary cause of death was deemed to be starvation, and the scavenging is clear evidence of its desperation in finding food (after several days of severe weather, included deep snow cover).

As discussed in original blog post, many of our owl casualties have been in excellent condition, including those recovered in the hard weather just over a year ago, but this latest finding is more expected given the evidence we now have of its significant impact on (but not elimination of) local breeding populations. Several other reports of Barn Owls in the region, including a courting pair, gives some grounds for optimism.

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