Individual study: Control of feral pigs Sus scrofa and captive-bred releases leads to a population increase of Lord Howe Island woodhen Tricholimnas sylvestris, New South Wales, Australia
Miller B. & Mullette K.J. (1985) Rehabilitation of an endangered Australian bird: the Lord Howe Island woodhen Tricholimnas sylvestris (Sclater). Biological Conservation, 34, 55-95
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Release captive-bred individuals into the wild to restore or augment wild populations of rails
A replicated study on Lord Howe Island, Australia, in 1981-3 (Miller & Mullette 1985) found that captive-bred Lord Howe Island woodhens Tricholimnas sylvestris survived for up to two years in the wild (released after a pig Sus scrufa and goat Capra hircus control programme had been running for several years, see ‘Control mammalian predators on islands’). In addition, 19 wild-bred young were reared successfully. Before captive breeding, there were only three pairs known in the wild, which were transferred to captivity. In total, 57 birds were released over three years. This study also describes the captive-breeding efforts, discussed in ‘Use captive breeding to increase or maintain populations’.
Control mammalian predators on islands for rails
A before-and-after study in 1979-84 on Lord Howe Island (56 km2), Australia (Miller & Mullette 1985), found that the Lord Howe Island woodhen Tricholimnas sylvestris population increased after feral pigs Sus scrofa were controlled and a captive breeding programme was launched. Before pig control, the woodhen population was a maximum of ten breeding pairs, with adult mortality higher than juvenile recruitment. Following pig control, 56 released, captive-bred birds were found to survive for up to two years and 19 young were successfully raised between 1982 and 1984. Additionally, woodhens have started to expand their range from the unfavourable territories they were previously confined to, to more favourable, previously pig-infested regions. A total of 186 were destroyed between 1979 and 1981. This study is also discussed in ‘Release captive-bred individuals’ and ‘Use captive breeding to increase or maintain populations’.
Use captive breeding to increase or maintain populations of rails
A study on Lord Howe Island, Australia, between 1980 and 1983 (Miller & Mullette 1985) found that Lord Howe Island woodhens, Tricholimnas sylvestris, successfully reproduced in a purpose-built breeding centre. In 1980, the only three healthy adult pairs of woodhen were taken into captivity and they produced 66 chicks which were reared in captivity. This study also describes the impact of predator control (see ‘Control mammalian predators on islands’) and release of captive-bred individuals (see ‘Release captive-bred individuals’).