The Yelkouan shearwater.

A Yelkouan shearwater has started using an artificial nest box that has been placed in an attempt to help the threatened seabirds to breed again.

Known as garnija in Maltese, the bird taking up the man-made nest had the potential to revolutionise the study of their breeding cycle, Benjamin Metzger, head researcher of EU Life+ Malta Seabird Project, said.

“Normally Yelkouans nest deep in the dark, narrow crevices and caves in the sea-facing cliffs around the islands, which makes their behaviour on their nest very difficult to observe,” he said.

However, if more of these seabirds were willing to nest in boxes, it should make it possible for researchers to gain insights into previously unobserved aspects of their breeding ecology.

“What happens to the birds during this vital stage of their lifecycle is hugely important if we are to understand why their populations are in decline and what we can do to help them recover,” Dr Metzger said.

One of the main factors responsible for limiting their breeding success is predation, especially by rats. The adult birds, which form long-term pairs, lay only one egg a year.

Malta is home to 10 per cent of the world’s breeding population of Yelkouan Shearwaters, which are listed as “vulnerable” in the International Union for Conservation of Nature, Red List of endangered species.

As well as studying the ecology of Malta’s threatened seabirds at their breeding sites, the EU LIFE+ Malta Seabird Project aims to identify important areas for seabirds in Maltese waters and designate special protection areas at sea under EU nature conservation legislation.