In the Brownie Story, it was the Wise Brown Owl who knew all about Brownies, and was able to show where they could continue to be found should any child seek one. So it was that although Guides might have a Captain and a Lieutenant, Brownies could best be guided by their own wise owl, a Brown Owl. So leaders trained to become Owls, and they had a special 'Warrant Badge' which they earned when qualified.
To run a unit, you worked to earn the Brown Owl's qualification, and for that you received a special Warrant Badge in the form of an Owl's Head, as shown on the left.
As a second adult was needed to run a good unit, the title of "Tawny Owl" was given to the assistant leader. To help with a unit, you worked to earn the Tawny Owl's qualification, and the special Warrant Badge for a Tawny Owl showed a full-length portrait of an owl
Although these badges always have brown enamel, the shade of it can range from a light honey colour through to a dark brown.
As in some countries, Owls either weren't known, or didn't get a good press, a warrant badge in the same style as for Guide Captains was used, but with brown enamel instead of green, Tawny Owls wearing a Lieutenant's badge - but these were not issued in the UK.
After Warrant Badges were dropped from the programme in 1968, these badges ceased being issued.