Wardens at Cemlyn Nature Reserve

09/08/2026

Now that the Sandwich Terns have left for Africa, it's time for wardens Kathleen and Jordan to depart too. We want to thank everyone who visited the birds and us on the ridge, and our reliable team of volunteers. The year was successful for Sandwich Terns, with around 1735 pairs. Over the season, at least 11 roseates (a very conservative minimum) dropped by the lagoon, as well as rarities such as the Curlew Sandpiper, Great White Egret, and a breeding Cuckoo!
Keep an eye out for a summary report of Cemlyn's breeding season, and drop by the lagoon in winter to see various waders such as Golden Plover. See you next year, when the terns 're-tern.

29/07/2026

Amazing Arctic terns... https://www.facebook.com/share/18bYfywZC8/

Some good news to start your Monday 🌞

This year, we had two special visitors at Rockabill and Dublin Port. In early June, BirdWatch Ireland staff caught an Arctic Tern that was first ringed in Dalkey Island, 2003—which made this bird 23 years old (pictured). Our team thought this was the oldest Arctic Tern caught in Ireland, until two weeks later, another tern at Rockabill beat that record. Jody, one of our Rockabill wardens, caught an adult Arctic Tern that was ringed on Rockabill as a chick 26 years ago!

Arctic Terns have the longest migration of any species and travel roughly 70,000 km a year, which means the 26-year-old tern has travelled about 1.82 million km. That’s almost 5 trips to the moon! 🌕

Thank you to our partners and supporters at National Parks and Wildlife Service, Dublin Port Company, Dublin Bay Biosphere, and Irish Nautical Trust who help make this work happen at Rockabill and Dublin Port! Photos taken under NPWS licensing.

22/07/2026

It's not quite "last chance to see" but the terns, especially Arctic and common, are starting to move on. There is still lots to see - roseate terns are still making occasional appearances and a great white egret is a bit of a treat. And a chance to compare young terns - like these Sandwich tern and common tern youngsters. Photos Kathleen Power and Steve Roberts

21/07/2026

While the terns still attract much of our attention – and numbers have started to dwindle – the seas have thrown up something of interest as well. Visitors have been noticing lots of spider crab carapaces on the tide line recently. These are the old hard shells, that the crabs have moulted out of in order to grow - sometimes up to 30% larger. In summer, spider crabs move to shallower waters to moult. It’s a multi-step process which involves using minerals from the old one to grow a soft exoskeleton inside the hard one, and enzymes to separate the rigid outer shell from the new inner shell. Next, the crabs absorb large amounts of water to swell their size and burst open their shell along a ‘moult line’. The crab then forces its way out of its own exoskeleton over a period of hours, extracting all its body parts - 10 legs, eye stalks and all! The process, known as ecdysis, can also regenerate lost limbs over multiple moults!

12/07/2026

Recently we had a real treat ... 5 bottlenose dolphins came into the Bay and were seen leaping and generally playing around. Always worth looking behind you when watching the terns! (Picture Nia Haf Jones/NWWT .. taken on a different occasion!)

11/07/2026

Sandwiches on a Saturday. The islands are now very busy with Sandwich tern chicks, some ready to fledge. It's amazing to watch as the young birds take to the wing for the first time. And among all the tern-based hustle and bustle, feeding and displaying, there is the odd Med gull juvenile. It's a great time to visit. Photos Kathleen Power

07/07/2026

Look back at events earlier this season - and those of previous years - in our Tern Diary

Follow a year in the life of the Cemlyn tern colony and keep up to date with all the latest wildlife news from North Wales Wildlife Trust

04/07/2026

In the evening light the whole colony takes to the air. Magical! North Wales Wildlife Trust

28/06/2026

The warm nights have meant that some amazing moths have been turning up at the moment... here are a few of our faves Elephant hawk-moth, buff arches, pebble prominent, eyed hawk-moth. We've been helped out by Steve Culley, a long time friend of past wardens in their moth-ing (and birding) adventures!

26/06/2026

Wonderful early morning photograph by volunteer Steve Roberts