Wednesday 1 March 2017

News from Namibia

Since autumn 2014 we have been colour ringing Common (Sterna hirundo) and Artic Terns (Sterna paradisaea) in Dublin Bay. We colour ring chicks under licence at the breeding colonies within the confines of the Liffey and Tolka Estuary. In addition, we catch and colour ring adult terns on Sandmount Strand where they gather en masse to roost ahead of autumn migration.

"PAT" a colour ringed newly fledged Common Tern
at Dublin Port
John Fox

Last year we received our first foreign (outside Dublin) colour ring resightings. They were made on the Isle of Lewis, Scotland (10/05/2016), Larne Lough, Northern Ireland (10/07/2016) and on Anglesey, Wales (13/07/2016). Since last season’s autumn migration things had turned quite on the resightings front until two very exciting emails arrived from West Africa in early January!

Two project ringed Common Terns were observed along the Namibian coastline by Mark Boorman a self-confessed “birder” and a veteran tern ringer (with thousands of terns ringed over the years)!

The first bird a Common Tern “PEX” was seen at Mile 4 Salt Works, Swakopmund, Erongo Region, Namibia (-22.597897, 14.519366) and had been ringed on Sandymount Strand, Dublin as a juvenile on 25/08/2015. Mark explained “At the Mile 4 site there are also Sandwich (Sterna sandvicensis), Great Crested (Thalasseus bergii), and sometimes Black Tern (Chlidonias niger) present. A post-breeding flock of Damara Tern (Sternula balaenarum) can be there in late summer. The large flocks of Common Tern are unpredictable as they will utilise any area which is close to their feeding area at that time. The birds roost on the edge of extensive pre-evaporation man-made pans in close proximity to the sea and also on the high beach.”

Mile 4 Salt Works, Namibia Google Maps

The second, again a Common Tern “PTU” was seen further south at Pelican Point (-22.882860, 14.439098). PTU was ringed as a juvenile four days later than PEX again on Sandymount Strand on 28/08/2015. Mark said “At Pelican Point once again the flocks are unpredictable and can gather from place to place. Here they will also be close (within a couple of hundred metres) to the sea. At times these flocks can number in their thousands.”

Pelican Point, Namibia Google Maps

In a straight line both sites are over 5400 miles away from the ringing site in Dublin, a good spin by anyone’s standard. In reality, the birds will have made their way down from Europe across into northern Africa and followed the coastline south, feeding and roosting at various staging areas along the way.

As always we are delighted to get such resightings back to us and records like this really show the value of colour ringing projects. Thanks to Mark for his efforts spotting and reading the rings which is not always an easy task! Soon we might be able to return the favour and find one of his birds in Dublin, we'll keep you posted.

It’s still too early in the year for Irish sightings but if you do encounter colour ringed terns and believe they might be Dublin Bay ringed birds please enter your sighting at the link below. We have created a new online web map for capturing these resightings, check out the details of the Dublin Bay scheme and enter your records here.

No comments:

Post a Comment