Overview
Shenick Island (Irish: Oileán na Sionnach) lies just east of the fishing town of Skerries in County Dublin. The island is uninhabited, its western shore a haul‑out for a colony of grey seals and its cliffs a nesting ground for several seabird species. Its most striking man‑made feature is a well‑preserved Martello tower, one of a pair built in the early‑19th century to guard the Irish Sea against a possible French invasion. At spring tide the island can be reached on foot across a sandbank; otherwise a short boat trip from Skerries Harbour is the usual approach.
Geography & Size
Shenick Island is the largest of the Skerries Islands, covering roughly 6.4 ha (15.9 acres). The island’s highest point reaches about 13 m (43 ft) above sea level, giving it a gentle, low‑lying profile. It lies approximately 1 km east of Skerries Harbour (coordinates 53°34′20″N 6°05′01″W) and forms part of the civil parish of Holmpatrick. The island is linked to the mainland at low tide by a tidal sandbank, creating a temporary causeway that can be crossed on foot.
History
The name “Shenick” derives from the Irish sionnach, meaning “fox”. In the 19th century the island became the centre of a bitter “seaweed war”. Local farmers from Rush harvested the abundant seaweed – known locally as “woar” – to spread on their fields as fertiliser. Landlord Ian Hamilton, who claimed ownership of the island under letters patent granted to the Earl of Thomond, tried to impose a fee on each load. He even built a wall to block access, prompting the farmers to smash it and launch a legal battle that lasted until 1896, when Hamilton finally won. The fee of one shilling per load persisted until 1946.
In 1917 the island was bought by Lawrence McDonagh and remained a family farm until the 1950s. Since 1987 the Fingal branch of the Irish Wildbird Conservancy Council (now operating as BirdWatch Ireland) has managed Shenick as a wildlife reserve, protecting its seal haul‑out and bird colonies. The Martello tower, erected in 1808, is still largely intact; the iron cooking grate survives, the wooden floors have vanished, but the spiral staircase and roof remain climbable.
The island is part of the Skerries Islands Natural Heritage Area, a protected landscape that also includes St Patrick’s Island and Colt Island. Local folklore links the island to St Patrick – a stone on the western shore is marked “St Patrick’s Footprint” and is said to be the spot where the saint first set foot in Ireland. An ancient well on the island, reputed to have curative properties, is sometimes mentioned in local stories.
Management & Conservation
The reserve is overseen by the Fingal branch of BirdWatch Ireland (formerly the Irish Wildbird Conservancy Council). Their work focuses on monitoring seal populations, maintaining the seabird breeding colonies and preserving the island’s unique geological exposures. Visitors are asked to stay on the marked path and keep a respectful distance from wildlife.
Geology and Designations
Shenick Island is recognised as a County Geological Site because it displays an inverted succession of Ordovician volcanic rocks (andesite, tuffs and shales) overlain by early Carboniferous red breccia and Quaternary boulder clay. These exposures illustrate a gap of over 200 million years and are a key reference point for the geology of the Leinster region. The island is also designated as a Special Protection Area (SPA 4122) and forms part of the Skerries Islands Natural Heritage Area (pNHA 1218), underscoring its importance for both geology and wildlife.
Wildlife Highlights
- Seals – Grey seals regularly haul‑out on the western beach, especially during the winter months when they come ashore to rest and breed. Numbers can reach several dozen individuals.
- Birds – The cliffs host thriving colonies: roughly 25 pairs of fulmars, 120 pairs of herring gulls and 25 pairs of great black‑backed gulls breed here. During migration the island supports large numbers of oystercatchers (up to 463), curlews (327) and turnstones (242). The site is a favourite stop for birdwatchers throughout the year.
- Flora – Low‑lying salt‑marsh plants and hardy coastal grasses dominate the sandbank and the island’s interior, providing food and shelter for the invertebrate community that underpins the bird and seal populations.
Because Shenick is a designated wildlife reserve, visitors are asked to keep a respectful distance from the animals and to stay on the established path.
Visiting Shenick Island
Tides & Safety
- The sandbank is exposed roughly two hours before and after low tide at spring tide, giving an hour‑long window on each side of the low‑water mark. Check the Irish Hydrographic Office tide tables before you go.
- The path can be slippery and is completely submerged at high tide. Wear sturdy, waterproof footwear and allow plenty of time to return to the mainland.
- Dogs are not permitted on the island due to its status as a seal and bird reserve.
Getting There
Walking
- At low spring tide you can cross the mud‑flat on foot. The walk forms part of the Skerries Coastal Walk, a scenic route that links the town’s promenade with the surrounding dunes and cliffs.
Boat trips
- During the summer months local operators such as Skerries Sea Tours and Skerries Harbour Boat Trips run short, guided crossings from the harbour. Trips typically last 15‑20 minutes and cost around €5‑€7 per adult. Exact contact details are not published online; visitors should ask for timetables at the Skerries Harbour information desk or via the Skerries tourism website.
Public transport
- Train – Skerries railway station is on the Dublin‑Dundalk line and is a 5‑minute walk from the harbour.
- Bus – Several Dublin Bus routes (e.g., 33, 33A) stop in Skerries town centre; from there it is a short walk to the harbour.
Practical information
- Opening hours & fees – The island has no formal opening hours and entry is free. The Martello tower is not staffed; visitors climb at their own risk.
- Facilities – There are no toilets, cafés or parking on the island. Use the amenities in Skerries town beforehand; free car parks are available near the harbour.
- What to bring – Pack water, a packed lunch, a wind‑proof jacket and a pair of binoculars for birdwatching.
- Photography – Early morning or late afternoon light gives the best contrast for seal and bird photography. A telephoto lens (200 mm +) is recommended.
Nearby attractions
- Balbriggan – A short drive north offers a pleasant seaside promenade and additional dining options. Balbriggan
- Burrow Beach – A popular sandy beach with facilities, ideal for a post‑island picnic. Burrow Beach
- Ardgillan Castle – Set on a coastal estate with gardens and walking trails, a good stop after a day on the islands. Ardgillan Castle