Flying across the Sahara sounds dangerous whereas landing on Anglesey relatively safe - but no.
There are five or so coastal colonies of sand martins on the island and one in the middle where the A5 and A55 cross the Cefni. Concrete structures either side of the river have low-lying drainage holes with nesting appeal. In recent years sand martins have found these irresistible, laid their eggs and maybe hatched them by the time spring tides swelled upstream and drowned them.
Last year, Ffred, from Kehoe Countryside Ltd, was commissioned by Jill Jackson of the North Wales Trunk Road Agency to build a sand martin wall. Half the drainage holes were blocked with chicken wire and 6 of the 96 new nesting holes were used. It seems the birds are not too bothered by the sound of traffic whizzing past.
To build on that success another wall has been commissioned on the opposite bank and all of the drainage holes will be blocked. Construction has been completed just in time for the arrival of the early migrants.
Here’s what the building site looked like in early March.