Introductions of mammalian predators have led to extinctions or declines of many species on islands; hence eradications of these mammals have played a major role in biodiversity conservation. However, eradications are costly and sometimes controversial. It is therefore important to conduct carefully designed sampling programmes that allow benefits to native species to be quantified.
Long-term data are needed to assess the impact of management initiatives such as mammalian predator-exclusion fences, but long-term monitoring programmes can be difficult to maintain. We used annual line transect distance sampling data collected by undergraduate students to model trends in native bird densities at Bushy Park, New Zealand, from 2002 to 2018, including 14 years of data collection following the installation of a predator-exclusion fence in 2005.
One of the quandaries faced by ecological researchers is whether they should continue to invest in ongoing projects or whether they should shift their attention to new species or systems that may have received less attention. While research on Tiritiri Matangi has touched on a wide range of species and topics, the long-term projects on the reintroduced robin population (20 years) and hihi population (17 years) have accounted for the bulk of the published research, with 57 papers featuring these populations published to the end of 2009.