Before the advent of pigeon post service in 1897 between Great Barrier Reef Island and Auckland, the few inhabitants had to rely on a weekly coastal steamer service. The service - which was so popular that it inspired a competitor to go into business - was the first ever airmail postal service, and these stamps were issued years before the Wright Brother's aeroplane even left the ground.
The practice of sending mail by pigeon actually dates back to the times of Julius Caesar, and perhaps even back to the Ancient Greek Olympic Games. Pigeons have been used for military, financial, and political purposes for centuries, and have helped with everything from domestic mail in New Zealand to secret correspondence during World War Two.
They're an oddly idiosyncratic form of transport: they can easily be intercepted, or even killed, during their flight. They can only deliver mail home, and this one-way route means that they have to be deliberately carried to the planned release site, whether that be in a different country or a town further down the coast. Pigeons require planning, protection and postage stamps.
They haven't even been abandoned today. Rocky Mountain Adventures, a kayaking and water sports company based in Denver, still employs a carrier pigeon to get digital copies of photographs on a memory stick from the riverside to the kiosk to print and sell. Out in the wilderness, there isn't always a wireless connection, and sometime it's best to resort to old-fashioned analogue airmail.
Sources:
'Homing Pigeons Get Down To Business', Katy Human, The Denver Post, 24/6/2007
The Pigeon, Wendell Levi, South Carolina, 1977
Museum of New Zealand online exhibits: Great Barrier Island Pigeongram Agency: Mail Form No 9 - http://collections.tepapa.govt.nz/objectdetails.aspx?oid=292735
