Bann Estuary - 17th August 2024

Bann Estuary - Saturday 17th August 2024

Over the past couple of weeks, up to three Ospreys had been seen around the Bann Estuary, where the river Bann flows out into the ocean between Castlerock and Portstewart.  Two of these birds bore colour-rings - (White) EY, and (Blue) NS2.  Today I decided to visit the Bann Estuary hoping to photograph both birds, especially - EY, as I photographed this bird on the 29th August 2023 and it would be great to record this one again.  Should neither bird be present, I should have been able to record some colour-ringed Sandwich Terns instead.  As it panned out during my visit, I had missed the presence of a single Osprey about an hour before I arrived, the info having been supplied by a gentleman in the hide overlooking the estuary.

I then moved into position to record the Sandwich Terns on an incoming tide.  A nice flock of up to 80 birds were in the area.  I found a nice position on the edge of the vegetation line from where I could scope the terns.  Keeping myself as small as possible, the birds would feel less threatened, therefore allowing closer approach as the tide came in.

At first, it was difficult to see colour-rings properly, although some birds did have them.  The problem was caused by the terns standing on shallow water which obscured the codes on them.  As the tide crept in further, the terns would take to the air, landing ever closer towards me.  A colour-ringed Oystercatcher was quickly sorted out, this one having a plain black ring on the lower left leg, with a metal ring on the upper left leg.  I quickly assumed that this was an Icelandic bird, which had lost a second colour-ring on the left leg, as there should be two plain colour-rings, and a coded colour-ring was missing on the right leg.

On returning home, I had a look at my spreadsheet to see if I could find any possible Oystercatchers having been recorded on the Bann Estuary over past years.  I did find one match, and this was - Yellow over Black on the left leg and - Grey (UY) on the right leg.  I reported my sighting to Boddi in Iceland, who replied a couple of days later.  B/Y-G(UY), was last sighted in September 2023 at Portstewart by my former ringing trainer John Clarke, and at that time, all rings were present.  Boddi thought it would be strange for the bird to have lost two colour-rings, but at the same time, he could not discount it.  The only solution would be to try and obtain numerals on the metal ring, which I did try without success.

Perhaps someone will have better luck over the coming weeks, especially as this bird should now remain in the area over the winter.

Oystercatcher  -  Bann Estuary, Castlerock, Co. Londonderry  (17 Aug 2024)

With the tide creeping ever closer, the terns began to settle down on drier sandy areas where I could scan through them with my camera.  By the time that I reckon all birds with colour-rings were photographed, on checking my photos back at home, I had recorded 7 birds in total.

Three of these belonged to my current ringing trainer, Richard Donaghey.  Richard has taken over a long standing ringing project concerning Sandwich Terns at Inch Island in County Donegal.  The project formerly belonged to Ken Perry, but when Richard took over, the colour-rings were then introduced into the study.  These three birds which I recorded were my first from Richard's Study, and my thanks goes to Richard for supplying the details.

 512 , was ringed as a chick on the 19th June 2019 on Inch Island.  Two previous sightings were made in July 2021 in County Donegal, and here on the Bann Estuary in September 2021.  The duration since being ringed, is now 5 years, 1 month and 29 days, and the Bann is situated 46 kms / 28 miles (ENE) from Inch Island.

Sandwich Tern  -   512   -  Bann Estuary, Castlerock, Co. Londonderry  (17 Aug 2024)

(Ringed as a Chick, on the 19th June 2019, at Inch Island, Co. Donegal, Republic of Ireland)

 527 , was also ringed as a chick, on the 19th June 2019, at Inch Island.  This one has three previous sightings - June 2022 on the Farne Islands in England, May 2023 in the Andalusia Region in Spain, and more recently, here on the Bann Estuary in July 2024.  The duration since being ringed, is now 5 years, 1 month and 29 days, and the distance from Inch Island, is 46 kms / 28 miles (ENE).

Sandwich Tern  -   527   -  Bann Estuary, Castlerock, Co. Londonderry  (17 Aug 2024)

(Ringed as a Chick, on the 19th June 2019, at Inch Island, Co. Donegal, Republic of Ireland)

 683 , was ringed as a chick, on the 24th June 2022, at Inch Island.  My sighting was a first for this bird, coming in after 2 years, 1 month and 24 days.  The Bann Estuary is situated 46 kms / 28 miles (ENE) from Inch.

Sandwich Tern  -   683   -  Bann Estuary, Castlerock, Co. Londonderry  (17 Aug 2024)

(Ringed as a Chick, on the 24th June 2024, at Inch Island, Co. Donegal, Republic of Ireland)

The fourth and fifth Sandwich Terns belonged to Roision Kearney's Study at the RSPB's Blue Circle Island Nature Reserve on Larne Lough, Co. Antrim.   3L0 , was ringed as a chick, on the 17th June 2021. 1 month and 18 days after being ringed, as a juvenile it was spotted here on the Bann Estuary.  In July 2023, it was then spotted at Stranraer in Scotland, before returning to the Bann Estuary the following month (15th August 2023).  Today's sighting take the duration since being ringed, to 3 years and 2 months.  The distance from Blue Circle to the Bann Estuary, is 75 kms / 46 miles (WNW), although the distance would be greater than this assuming the bird is flying around the coast.  I already had details for this tern on my spreadsheet.

Sandwich Tern  -   3L0   -  Bann Estuary, Castlerock, Co. Antrim  (17 Aug 2024)

(Ringed as a Chick, on the 17th June 2021, at Blue Circle Island, Larne Lough, Co. Antrim)

I am still waiting for a reply from Roision concerning both of my sightings.  The second bird -  3C9 , will also have been ringed as a chick.  I will edit this section once Roisin supplies me with details.

Sandwich Tern  -   3C9   -  Bann Estuary, Castlerock, Co. Londonderry  (17 Aug 2024)

(Ringed as a Chick, on the )

A Sandwich Tern with a plain Red Marker Ring was also spotted.  Some details about the history of these plain rings are known.  They were used by Alistair Smith who sadly died before all of the records for these rings were released.  What is known, is that Alistair used the same colour to ring all chicks at the Ythan Nature Reserve in Aberdeenshire, Scotland.  In each subsequent year, a different colour or a combination of two colours were used on each years chicks.

The problem, is that we do not know the year each colour was used, but this changed when Ewan Weston began using colour-coded rings at Ythan.  It could be possible, that surviving birds from Alistair's time could be over 20 years of age.

On my spreadsheet, I have two examples of these Red Marker Rings.  The first here at the Bann Estuary was recorded on the 15th August 2018, when Richard Donaghey had a bird with Blue over Red.  Today's bird, might possibly be the same one having lost the Blue Ring.  The second example, was that of a sighting made by Suzanne Belshaw on the 22nd September 2019.  On this occasion, Suzanne photographed a Sandwich Tern with a single plain Red Marker Ring on Kinnegar Beach at Belfast Lough.

We will never know the true circumstances of these Sandwich Terns.  Only by reading the metal numbers, can we obtain the true date of ringing, and it would be a 'tall order' to read these metal rings.

Sandwich Tern  -  Red Marker Ring  -  Bann Estuary, Castlerock, Co. Londonderry  (17 Aug 2024)

(Ringed on the Ythan Estuary, Aberdeenshire, Scotland)

My final Sandwich Tern sighting was the best of the lot.  Having obtained the code -  N39 , I checked the cr-birding site, and found that the ring was Dutch.  I sent an email to Mardik Leopold, who replied with the birds details.  My sighting turned out to be a first for this bird.  It was ringed during a ringing expedition to Senegal, where Senegalese metals were used in conjunction with Dutch colour rings.  

The bird was ringed on the 1st April 2023 as an unsexed adult, at La Langue de Barbarie.  This then reminded me about another Sandwich Tern which I also recorded here on the Bann Estuary on the 29th August 2023.   N57 , was ringed at La Langue de Barbarie on the 29th March 2023 during the same ringing expedition.  Better than that, I was informed this summer of another sighting of -  N57 , this time, on the 1st July 2024, at a breeding colony in Holland.

The distance from La Langue de Barbarie to the Bann Estuary, is 4,442 kms / 2,760 miles (NNE), and the duration since -  N39  was ringed, is now 1 year, 4 months and 16 days.  My thanks goes to Mardik for his quick reply.

Sandwich Tern  -   N39   -  Bann Estuary, Castlerock, Co. Londonderry  (17 Aug 2024)

(Ringed as an Unsexed Adult, on the 1st April 2023, at La Langue de Barbarie in Senegal)

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