Gronant's Little Tern Colony

The Council's Countryside Service manages Gronant Dunes, on the border of Denbighshire and Flintshire. Gronant, together with its satellite colony at Point of Ayr, is Wales’ only breeding colony of little terns¹. The colony is the second largest in the UK, and one of the most successful, with Denbighshire having managed the colony since 2005.

With the help of volunteers from North Wales Little Tern Group, staff from Denbighshire Countryside Service and Keep Wales tidy constructed over 3km of electric fencing over shingle nesting habitat in April. Its purpose is to protect nests from predators, as well as disturbance from visitors. Three Little Tern Wardens are based at the colony throughout the season, and work shifts to ensure a daily staff presence. Their role involves protecting the little terns from predators, maintaining the electric fencing and marking and recording nests. Denbighshire have been working with two licenced bird ringers, with over 35 years’ experience of working with little terns. The ringers are collecting valuable data which will build a more in-depth understanding of these birds. For instance, ringing at Gronant helped to discover the oldest known little tern, at 25 years old²!

Since the beginning of the Covid-19 pandemic in 2020, there were concerns over how Denbighshire would be able to manage the little tern colony, who were unable to employ Little Tern Wardens or work with volunteers as lockdown hit. Throughout the 2020 season, Gronant was managed by a small number of Denbighshire staff. Despite best efforts, many nests were lost to unusually high tides, with many more lost to predation. However, this year, the colony has gone from strength to strength, with the latest count recording 198 nests, and an estimated 380 adult birds present on the 3^rd of June. This is a significant proportion of the UK population, believed to be around 1450². Denbighshire were able to recruit the Little Tern Wardens once again, who, with the help of North Wales Little Tern Group, are keeping a watchful eye over the colony. Although public engagement is still limited, the colony can still be seen from a safe distance by visitors, outside of the fenced-off area. Recent improvements to the boardwalk and paths on the site has created better access, encouraging more visitors to come and enjoy Gronant and its bird life.

High tides at the end of May were a cause for concern, but there was only minimal damage to fencing and no nests were lost. There are hopes that the 2021 season will be as successful as 2019, which was one of the best to date, with 162 breeding pairs and 206 fledglings recorded³. Denbighshire Countryside Service will continue to manage the little tern colony over the summer, until the chicks have fledged and the birds return to Africa for the winter.

If you would like further information about the Little Terns at Gronant, then please contact Claudia at claudia.smith@denbighshire.gov.uk.

We've also got some facts for you as well, namely:

• The breeding season starts in May, and continues until early August.
• Breeding pairs construct nests out of scrapes in the shingle.
• Male and female adults both take turns to incubate the nest, although males spend proportionally more time fishing, while females spend more time at the nest.
• Chicks typically take 10-21 days to fledge from hatching.
• Chicks are fed predominantly on a diet of sand eels.
• Adult little terns protect their young by mobbing any predators which get too close.
• Common predators include kestrel, peregrine falcon, crow and fox.
• As well as little terns, shingle provides nesting habitat for oystercatcher and ringed plover.
• In August, little terns travel thousands of miles to West Africa, where they spend the winter, and then travel back to the UK to breed in May.

.References

1. JNCC: our work https://jncc.gov.uk/our-work/little-tern-sternula-albifrons/#distributionabundance
2. BTO Bird Facts: Little Tern https://app.bto.org/birdfacts/results/bob6240.htm
3. 2019 Little Tern Report