Biodiversity

The impacts of house mice (Mus musculus), one of four invasive rodent species in New Zealand, are only clearly revealed on islands and fenced sanctuaries without rats and other invasive predators which suppress mouse populations, influence their behaviour, and confound their impacts. When the sole invasive mammal on islands, mice can reach high densities and influence ecosystems in similar ways to rats.

Following the incursion of rats (Rattus rattus) on Taukihepa (Big South Cape Island; 93.9 km²) off southern New Zealand in 1963, and the subsequent extirpation of several endemic species, the New Zealand Wildlife Service realised that, contrary to general belief at the time, introduced predators do not reach a natural balance with native species and that a safe breeding habitat for an increasing number of ‘at risk’ species was urgently needed.

Rat eradication is a highly effective tool for conserving biodiversity, but one that requires considerable planning eff ort, a high level of precision during implementation and carries no guarantee of success. Overall, rates of success are generally high but lower for tropical islands where most biodiversity is at risk. We completed a qualitative comparative review on four successful and four unsuccessful tropical rat eradication projects to better understand the factors influencing the success of tropical rat eradications and shed light on how the risk of future failures can be minimised.

Invasive alien plants and animals are known for their disruption of ecosystems and threat to biodiversity. This book highlights their major impact on human health. This includes not only direct effects through contact with the species via bites, wounds and disease, but also indirect effects caused by changes induced in ecosystems by invasive species, such as more water hyacinth increasing mosquito levels and thereby the potential for malaria.

The mitigation hierarchy (MH) is a step-by-step tool used to limit the negative impacts of development projects. It can be used for many disciplines; this guidance note focuses on its use to manage risks and impacts to biodiversity. Very similar approaches can be used for ecosystem services and even social impacts.

Climate change is one of the greatest ecological, economic, and social challenges facing us today. The scientific evidence that human activities are contributing to climate change is compelling, but society is increasingly seeking information about the nature of the evidence and what can be done in response to a changing climate. This book provides some of that much-needed information from some of Australia's leading climate scientists.

Millions of people are crowded along the coastal fringes of continents, attracted by rich fertile land, transport connections, port access, coastal and deep-sea fishing, and recreational opportunities. In addition, significant populations live on oceanic islands with elevations of only a few meters. Many of the world's megacities, cities with populations of many millions, are situated at the coast, and new costal infrastructure developments worth billions of dollars are being undertaken in many countries.