Northwest Brook Nature Reserve protects a high concentration of rare lichens along Northwest Brook, between Jordan Falls and Sable River, on the South Shore.

The reserve lies within a band of humid coastal forests and wetlands that supports many lichen species. The Northwest Brook area is known for blue felt lichen, powdered moon lichen, peppered moon lichen, blistered tarpaper lichen, black-foam lichen, veined shingle lichen, and naked kidney lichen. These all grow on trees. Protection of this site protects the lichens directly and helps prevent changes in microclimate caused by land disturbance that can negatively affect lichens.

A forest access road which bisects the nature reserve is not within the boundary and remains open to vehicle use.

Final boundaries were slightly modified through the survey process to improve survey efficiency and simplify management of the reserve.

Nature reserve designation of an additional 130 hectares along Northwest Brook will take effect if overlapped mineral rights expire and no new rights are granted.