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)

Friday, 28 November 2008

The long and tortuous road of reading metal rings

This site opened its account, from what I can remember, with the last few numbers of a juvenile Shag ring, which was partly-read whilst perched on one of the scenically-challenging platforms by the waterfall in the south west corner of Heysham Harbour. The number was read in full by John Wood today.

The status of Shag in Lancashire was formerly summarised as "one-two storm-blown individuals per year, usually juveniles after autumnal gales". However, recent events at Heysham have completely changed the status of this species in Lancashire, with double-figure counts in two of the last three autumn/early winters. Similarly, two other recent years have produced at least 5 individuals and it is clear that, for an unknown reason, this species is increasing both at Heysham and around the nearby Walney and Rossall inshore areas. This is definitely not due to an increased severity of autumnal gales, quite the opposite (see recent Leach's Petrel status [excluding the December 2006 wreck]). Indeed, this autumn's influx, involving a minimum of 11 individuals, took place during quite benign conditions in late August/September, perhaps just a short movement by part of an already substantial gathering around Walney Island.

As can be seen in the recently published Lancashire County Avifauna, most of the ringed autumnal storm-blown juvenile Shags have originated from Puffin Island on Anglesey. However, this is the first ringed bird out of at least 30 examined at Heysham during the last three years and this suggests that a majority might not be from this "well-ringed" source.

Just in case there has been more than one bearing a ring, the first date when the ring was (in the event conclusively!) part-read is used for the 'formal' ringing details. Therefore, no vague presumptions concerning a ringed juvenile Shag which had been present since late August:

Ringed: Puffin Island, Anglesey Pullus (from brood of 3) 7/6/08
Read in field: Heysham Harbour area: at least 26/10/08-at least 28/11/08

Note that the reason the partly-read ring was (after some research) confidently ascribed to this individual was due to the fact the bird was aged, and known to be bearing a ring issued and fitted in 2008. Its still nice to get the fully-read ring in the field, however.......just in case there is a future query!

Thanks to all involved in documenting this bird

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