Central to the growing field of island ecological restoration is the removal of invasive rodents. The lack of information on rodent tropical ecology is a limiting factor for the success of such eradication attempts on tropical islands worldwide. In Mexico, 14 successful rodent eradications have occurred, 6 of them on dry and wet tropical islands, and the others on temperate islands. All recent projects included research components in order to inform management strategies. Here we summarize the main research findings and management recommendations, using the case of Isabel Island to illustrate how efficacy and efficiency of conservation initiatives can be improved when informed by directed research.

Internationally, over the last 20 years the number of tools available for the control of small mammals has declined. Through the efforts of research we have bucked this trend and retained and developed new tools. Three new toxins have been extensively researched and registered, namely para-aminopropiophenone (PAPP) in 2011 for stoats and feral cats; zinc phosphide for possums in 2012; and encapsulated sodium nitrite (ESN) in 2013, for possums and feral pigs. The development of PAPP and ESN, coined red blood cell toxins, developed for humaneness, represent the first new vertebrate pesticides registered for field control of mammalian pests anywhere in the world for >30 years. Research on rodenticides including diphacinone with the additive cholecalciferol (D+C) and a palatable form of norbormide continues. A New Zealand EPA application for D+C was filed in June 2015. More effective killing systems are being researched, and the first successful field trials of resetting toxin delivery devices for possum and stoat control were completed in 2013 and 2014. Improved deployment strategies, integration of humane and selective toxins, lures of greater potency, and improved killing devices aided by species’ recognition will transform ground control for endangered species protection. Sodium fluoroacetate (1080) and other important tools have been retained as new tools are emerging from a research and development pipeline. It is important for the future of New Zealand’s biodiversity that this focused research continues and we continue to learn and advance new technologies. Our goals are shifting to enable reduction in density of rat, stoat, and possum populations to zero over large scales (i.e., elimination at landscape scale), and to hold these at zero through detection and response, including the use of new technologies for perimeter control as part of barrier systems for conservation.