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, 11 February 2013

An ancient darvic ring?

Administration at the ringing office ground to a halt when a Kittiwake with a darvic ring black on yellow H32 was photographed at Heysham about a week ago.  There was no trace of it!  It is still at Heysham and here is a much better pic taken today:

I dont know what the longevity record is for darvic rings of this size, but the wintering Broadway (now metal-ring-only) Med Gull used to possess one which lasted about 7 years and similarly, the last time Polish P96 was seen around Lancaster (2 winters ago), the ring looked like it was about to drop off - and this bird is either an intermittently seen 'unread metal-only bird' or it has disappeared altogether.  So 10 years sounds a reasonable age for a darvic ring, but this one should be 24 years old!

Assuming this is the same bird which was originally ringed with H32, the history is as follows
Ringed:  as a pullus at Waterford, Ireland in 1989
Seen: Seaforth Nature Reserve 25/5/1991, 11/6/1991, 16/8/1998
This information was obtained in the late 1990s by Steve White but he cannot remember how (Steve deals with hundreds of darvic and metal-ringed birds at Seaforth)

Seen: Seaforth Nature Reserve 23/8/2008 (photo). 
Unbeknown to Steve White, this had been sent in by another observer, but 'no trace found of origin'.  It came to light after the Heysham sighting was posted on the Heysham Obs Blog:

Seen:  Heysham Harbour 5/2/2013-(at least)11/2/2013   
This bird is currently residing around the waterfall in the harbour.  Whilst it might have seen the Peel Ports logo and felt just at home here as at Seaforth, this area of the harbour is very much a rehab or zimmerframe zone....and this is the last remaining Kittiwake after the strong onshore winds.  Hopefully it will survive and perhaps reappear at Seaforth or, better still, prove to be one of the nesting birds at the "new" colony along the docks at Liverpool

The metal ring was photographed today, albeit underwater but the photograher said that there didnt appear to be any visible letters or numbers - that would certainly fit with it being a 24-year old ring!

However, the jury is still slightly out on this one until it can be proven beyond doubt that a darvic ring can stay on a seabird for 24 years.  The case does seem pretty compelling however.  In no way should this account be interpreted as a slight on the efficiency of the BTO as they were not involved in monitoring colour rings at the time of ringing and this is an old scheme which had neither registered on the BTO radar, nor the Dirk Raes site - probably the only bird left alive and almost certainly the only up and still running darvic ring from the project!

Thanks to Janet Packham for the published pics.

Pete Marsh

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