We do NOT recommend this wool for use with captive bird. NEVER introduce nest material into the nest space artificially in clumps as this can lead to entrapment of the birds. Provide nesting material between February and July. The wool may be offered in its laminated box with a hole at the front so that that birds can tease out single threads, one at a time. Alternatively, the wool can be put in a spiral feeder to allow single threads to be taken. This pack of natural washed British sheep's wool offers valuable material for wild birds to line their nests. This improves insulation for young chicks during cold weather. From the Highlands of Scotland to the South West's rolling hills, wild birds seek out this natural material known for its strength, softness and warmth.