Not a tern for the worse

A record number of Common Terns are expected to return and hatch on Leeside this breeding season, April to August 2023.

The prediction came as details of the Port of Cork Company’s (PoCC) renesting and conservation project were recently unveiled.

The project aims to protect the Common Tern, an amber listed migratory seabird. PoCC said following a pattern of year on year growth, and a successful 2022 season, resulting in a total of 131 nests, producing at least 200 young birds, record numbers of chicks are expected to hatch this year.

Many of these birds are expected to return to Cork harbour to breed, PoCC has said.

Since 2010, a sub-colony of terns has nested at Ringaskiddy and this breeding site quickly became the largest in Cork Harbour. Unfortunately, for a number of years, chick survival at this nesting site became extremely low. In 2017, PoCC proposed a number of conservation measures to be implemented in Ringaskiddy in order to protect the bird species.

The measures included the introduction of purpose-built pontoons in Cork Harbour with the aim of providing a protected breeding site for the endangered bird and its offspring. The pontoons provide the ideal nesting substrate and are designed to exclude predators, particularly otter and grey heron which have taken many young birds in previous years.

The sites are monitored closely during the breeding season by UCC students from the School of Biological, Earth and Environmental Science at University College Cork, and overseen by a professional ornithologist.

Toddy Cuthbert, Environmental Support Manager at the Port of Cork Company, said: “It is important to play our part in supporting local biodiversity and promoting wildlife conservation in the harbour. A large number of terns have nested on these purpose built pontoons over the last few years and we are now looking at increased numbers of Common Tern expected in Cork Harbour for 2023. We are delighted to see that these pontoons are proving to be successful in protecting these endangered birds.”

Barry O’Mahony, Ornithologist, Department of Zoology, Ecology and Plant Science, UCC said: “Common Terns nesting in Cork Harbour are a very valuable addition to the local bird diversity. They can be seen from Lough Mahon to Crosshaven throughout the summer months as they plunge-dive for fish and commute to and fro between the foraging areas and their colony.

“With the support of the Port of Cork and Industries in the Ringaskiddy area, existing nesting areas have been protected, new nesting areas on pontoons have been created and protection from predation has been enhanced. These supports are critical in ensuring that the breeding colonies are protected and their future is assured as the development of Cork Harbour continues into the future.”

After several years of monitoring, perseverance and commitment, it is now the view of the PoCC team and their consultants that an effective pontoon structure providing fit for purpose nesting habitat with appropriate anti-predator measures incorporated into its design has been achieved.