Wicklow Reef

{{Infobox protected area

| name = Wicklow Reef

| alt_name = Sceir Cill Mhantáin

| photo =

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| map = Ireland

| relief = 1

| map_caption = Location in Ireland

| location = County Wicklow, Ireland

| nearest_city =

| coordinates = {{coord|52.9736|N|5.95683|W|format=dms|display=inline,title}}

| coords_ref =

| area_acre = 3790

| established =

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| designation = Special Area of Conservation

| governing_body = National Parks and Wildlife Service

| website =

}}

The Wicklow Reef ({{Irish place name|Sceir Cill Mhantáin}}) is a shallow subtidal reef in the Irish Sea, located off the coast of County Wicklow, Ireland, approximately {{convert|2.88|km|mi|adj=|sigfig=3}} northeast of Wicklow Head. The reefs are constructed by the honeycomb worm (Sabellaria alveolata) and are located at a depth of {{convert|12 to 30|m}}.{{cite web|title=Wicklow Reef SAC - Site Synopsis|url=https://www.npws.ie/sites/default/files/protected-sites/synopsis/SY002274.pdf|access-date=14 May 2022|work=National Parks and Wildlife Service}}

Prior to the discovery of the Wicklow Reef in 1997, Sabellaria alveolata reefs were only known to occur in inter-tidal zones along the coasts of Britain and Ireland. Sub-tidal reefs are exceptionally rare in the region, being typically found in the Mediterranean. The Wicklow Reef is the first and only known example of a sub-tidal Sabellaria alveolata reef off the coast of Britain and Ireland.{{cite web|title=Wicklow Reef SAC - Conservation objectives supporting document|url=https://www.npws.ie/sites/default/files/publications/pdf/002274_Wicklow%20Reef%20SAC%20Marine%20Supporting%20Doc_V1.pdf|access-date=14 May 2022|work=National Parks and Wildlife Service}}

The reef is home to a number of species of crab, starfish, sea-squirts, brittlestars, as well as molluscs and bryozoans. Several species of worm such as Phaeostachys spinifera, Eulalia ornata and Unciola crenatipalma are very uncommon in Irish waters, and the Wicklow Reef is therefore considered a priority habitat. The reef is an EU-designated Special Area of Conservation.{{cite web|title=Factsheet - Wicklow Reef SAC|url=https://eunis.eea.europa.eu/sites/IE0002274|access-date=14 May 2022|work=European Environment Agency}}