Abstract: A gas permeable package is provided that is comprised of a bonded, gas permeable, fibrous sheet material consisting of continuous lengths of bonded plexifilamentary fibril strands of a polyolefin polymer and a pigment. The polyolefin comprises at least 90% by weight of the fibril strands and the pigment comprises between 0.05% and 10% by weight of the fibril strands. The polyolefin polymer is preferably selected from the group of polyethylene, polypropylene, and copolymers comprised primarily of ethylene and propylene units, and is more preferably polyethylene. The pigment is preferably titanium dioxide. The fibrous sheet material has a basis weight of less than 85 g/m2, a delamination strength of at least 60 N/m, and an opacity of at least 90% if the sheet has a delamination strength less than 120 N/m, an opacity of at least 85% if the sheet has a delamination strength between 120 N/m and 150 N/m, and an opacity of at least 80% if the sheet has a delamination strength greater than 150 N/m.