Monday, 19 November 2012

They're terning up everywhere!

Since 2010 we have fitted inscribed colour rings (darvics) to nearly 600 sandwich terns on and around the Ythan estuary in North-East Scotland.  All but 90 have been captured as fully grown birds during the late summer and early autumn (July, August and September). During the short time since we started colour ringing them we have had 455 sightings. With the project coming into its third winter we are starting to get some really interesting results.
The first bird to make it back to its wintering haunts was ETT, originally ringed in September 2010 and sighted 5 times last winter in Namibia. By the time this bird had made it to its wintering grounds there were still a few stragglers in and around the UK. While a majority of Sandwich Terns winter in West Africa a small number brave the Northern hemisphere winters and we have been lucky enough to have 2 such birds so far this winter.

The first bird EHP was ringed on the Farne islands in 1996 as a chick and later recaptured on the Ythan Estuary in late July 2011 when it was given its individual colour ring. EHP was also the 3rd oldest sandwich tern we have caught with the oldest being ringed in 1986 in Northumberland.  Last winter EHP was sighted in southern England on 3 occasions between mid-September and late November. The next sighting and the photograph above came from across the channel in France at a site where over 50 Sandwich Terns were spending the winter. EHP was seen back in Portsmouth in early November ready to spend another winter in the English Channel.

Another Northern wintering tern has recently been reported in Douarnenez, France on 3 occasions during this November and had been seen in the same area in late November 2010. Apparently a small flock of 5-15 sandwich terns regularly winter there now. Unlike the Farne Island’s bird we are unsure of where this bird was hatched as it was unringed when we caught it in 2010. We do however know that this bird breeds in North-east Scotland on the Ythan estuary where we have sighted the bird this summer in the colony alongside 50 other colour ringed sandwich terns. So while some of the Scottish breeders such as EAN below are sunning themselves at the end of an arduous migration to winter 9,000km away a few individuals are braving the winter only 1,000km away.

Thanks to Mark Boorman, Jenny Lennon, Jean Pierre Marie & Gilles Coulomb for the fantastic photos. Any sightings of Sandwich Terns with colour rings starting with the letter E should be sent to ewan_weston  "at"

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