In 1891 the New Zealand government reserved Resolution Island, in Dusky Sound, as a refuge for ground birds such as kakapo and kiwi who were severely threaten with extinction due to introduced predators such as stoats, weasels and ferrets. Irish-born Richard Treacy Henry (1845-1929), who had arrived in New Zealand from Australia around 1874, was appointed curator of the reserve in 1894. In effect this made him New Zealand's first conservation officer.

Henry, who had a deep interest and knowledge of the natural world since childhood, had focused in particular on New Zealand native birds and the threats they were under from new predators. Predators such as stoats, weasels and ferrets had been released in New Zealand to combat another pest, rabbits, which had been introduced in the 1860s and were, by the 1870s, a major problem in many parts of the country. New Zealand's flightless birds proved to be easy prey for the introduced predators and their populations began to quickly decline. It became obvious to a number of people that species such as the kakapo would soon be wiped out.

Henry and an assistant, Andrew Burt (then around 18 to 20 years old), were placed on neighbouring Pigeon Island, where they built a house, store and boatshed on the northern coast. Initially Henry focused on relocating birds from the mainland and Pigeon Island to Resolution and other island sanctuaries, moving over 700 grey kiwi, 'roas' (brown kiwi) and kakapo. He also sent around 100 birds to reserves, botanical gardens and so on around the country. He pioneered ways of capturing and transporting birds and proved that they could be successfully relocated.

His Bird Pen on Pigeon Island was constructed as part of his work and is the most visible remnant of the New Zealand's government's first attempts at conservation. The only other relic of Henry's pioneering conservation work is the ruins of the house's chimney, although further archaeological evidence may still be present. One of the problems Henry had was keeping the birds alive until they could be shipped off the island. One of the main problems was the sand flies, which attacked the birds, to the extent that two died. To combat this he 'made a little paddock for roas (brown kiwis) out of pungies because they worry so much trying to get through the netting, also a dark house for them to avoid the sand flies'. (Hill:1987 p.225) This pen consisted of a rectangular arrangement of upright punga logs set in the ground, which was probably roofed. It is thought to have been much taller when first constructed. Today the logs stand, on average, around half a metre high.

Resolution Island had been chosen as a sanctuary because it was thought far enough off the coast for predators to swim to. However, in 1900 either a stoat or weasel was sighted on the island and the project was doomed. Henry began moving birds to other outlying islands, but not all of these were suitable habitats and, when the area was checked for kiwi and kakapo in 1980, none were found.

In 1908 Henry was appointed as ranger to Kapiti Island, near Wellington, where he stayed until 1911. He retired up north in 1912 and died in the Auckland Mental Hospital, Avondale in 1929. The kakapo, which he had fought to preserve, were left to languish until the 1950s. The recently established Wildlife Service began expeditions to find kakapo, mainly in Fiordland and caught six males, all but one of which died within a few months of being caught. By 1977 18 males had been found in Fiordland, but with no females it seemed that the kakapo would die out. That year, however, around 200 kakapo were found in Stewart Island, both male and female. Although free from stoats, rats and weasels, the Stewart Island kakapo were under threat from feral cats and it was decided to move the entire population to off-shore predator-free islands; Whenua Hou (Codfish Island) in Foveaux Strait, Maud Island, and Little Barrier Island in the Hauraki Gulf. These, along with the one surviving mainland kakapo, known as 'Richard Henry', became the focus of attempts by the Wildlife Service and subsequently the Department of Conservation to preserve the species. Eighty-six kakapo are known to exist now, a substantial increase from a low point of 51 in 1995. Henry's early work with the kakapo played a major role in later attempts to preserve the species; his technique of using a muzzled dog was found to be the best way of capturing the birds and the first female kakapo found on Stewart Island was identified as such using Henry's earlier descriptions.

Richard Henry's Bird Pen is of major historical significance to New Zealand. Erected as a practical response to the difficulties of housing captured birds, it is one of the few remains of the first state-funded conservation project in New Zealand. It is also significant as a reminder of Henry's personal dedication and struggle in one of the most isolated parts of the country. His project can be seen as an early indication of the importance attached to New Zealand's endangered birds, and the growing sense of national identity with them, which continues strongly today.