In the 6th Century, Bernera was settled by monks of the Irish Culdee church under the leadership of St. Moluag.St. Columba used the island as a private place for retreat, meditation and prayer, and may have preached under (and possibly planted) a vast yew tree. It is reported that the wood was turned into a staircase for Lochnell Castle at Ardmenhuis and survived at least two fires, which burned down the rest of the building.
The island has the remains of an ancient chapel and burial ground.
The common seal is a regular visitor to the coastal strip between the high and low water marks. This littoral zone forms part of the Eileanan agus Sgeirean Lios mòrSpecial Area of Conservation along with the nearby islets of Eilean na Cloich and Eilean Dubh in the Lynn of Lorn to the east and Dubh Sgeir and Eilean Gainimh in the Lynn of Morvern to the west.