NLRG was formed in 1957 to help in the study of birds in the Lancaster and District Birdwatching Society area. There are currently 12 active ringers. Species currently being studied include: Pied Flycatcher, Bearded Tit, Sand Martin, Twite, Goosander, Oystercatcher and Grey Wagtail. Migration has been studied for 28 years at Heysham. We welcome anyone who wants to observe, help or perhaps wish to become a ringer. Photo: A Heysham-ringed Twite on the Mull of Kintyre (thanks to Eddie Maguire)

Monday, 25 May 2009

Nest Box News No 2 Tawny Owls

Photos Chris Hoyle
The four pairs of Tawny Owls in our nest boxes this year appear to be struggling somewhat. Looking back through our records, average clutch size in previous years has been just short of 3 eggs. This year all four pairs have just two eggs each. Average brood size in previous years worked out at 2.4 per nest. This year only one pair has 2 young the others started with 2 but now have only one.
The reason for this poor productivity is probably the low numbers of small mammals this year. This scarcity has been commented on by a number of observers and may well be affecting other predators. Small mamal numbers tend to be cyclic with this year being at the low point of the cycle.

The photos show a Tawny Owl which has been hunting in daylight in a garden near Kirkby Lonsdale successfully taking small birds. Further evidence that their normal prey is scarce.

John Wilson

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