This is a midden, the archaeological term for a refuse deposit made up largely of shellfish remains, animal bone, and other domestic waste. Where soil conditions are right, such deposits can survive for centuries or millennia, their shells slowly mineralising while preserving traces of diet, season, and settlement nearby.

The deposit at Bunowna runs in varying concentrations along the full length of this north-facing earth-and-rock face, stretching from a towerhouse to the east all the way to the outflow of the Easky River to the west. The heaviest concentration sits at the river mouth, where the midden appears as a band roughly four metres long and about eight centimetres thick, set within a noticeably darker layer of soil some thirty centimetres below the top of the face. The proximity to both the river and the towerhouse is suggestive; towerhouses were the fortified tower residences of Gaelic and Anglo-Norman lords, common across Ireland from the fourteenth to the seventeenth centuries, and the people who lived in and around one would have relied heavily on whatever the local coastline and waterways provided. Shellfish gathering, being labour-light and reliably productive along a rocky shore, would have been a routine part of that economy.