Jamie K. Reaser

Ecological and socioeconomic impacts of invasive alien species in island ecosystems

Minimizing the impact of invasive alien species (IAS) on islands and elsewhere requires researchers to provide cogent information on the environmental and socioeconomic consequences of IAS to the public and policy makers. Unfortunately, this information has not been readily available owing to a paucity of scientific research and the failure of the scientific community to make their findings readily available to decision makers. This review explores the vulnerability of islands to biological invasion, reports on environmental and socioeconomic impacts of IAS on islands and provides guidance and information on technical resources that can help minimize the effects of IAS in island ecosystems. This assessment is intended to provide a holistic perspective on island-IAS dynamics, enable biologists and social scientists to identify information gaps that warrant further research and serve as a primer for policy makers seeking to minimize the impact of IAS on island systems. Case studies have been selected to reflect the most scientifically-reliable information on the impacts of IAS on islands. Sufficient evidence has emerged to conclude that IAS are the most significant drivers of population declines and species extinctions in island ecosystems worldwide. Clearly, IAS can also have significant socioeconomic impacts directly (for example human health) and indirectly through their effects on ecosystem goods and services. These impacts are manifest at all ecological levels and affect the poorest, as well as richest, island nations. The measures needed to prevent and minimize the impacts of IAS on island ecosystems are generally known. However, many island nations and territories lack the scientific and technical information, infrastructure and human and financial resources necessary to adequately address the problems caused by IAS. Because every nation is an exporter and importer of goods and services, every nation is also a facilitator and victim of the invasion of alien species. Wealthy nations therefore need to help raise the capacity of island nations and territories to minimize the spread and impact of IAS.

Saving camels from straws: how propagule pressure-based prevention policies can reduce the risk of biological invasion

Nonnative species that harm or have the potential to cause harm to the environment, economy, or human health are known as invasive species. Propagule pressure may be the most important factor in establishment success of nonnative species of various taxa in a variety of ecosystems worldwide, and strong evidence is emerging that propagule pressure determines both the scale of invasion extent and impact. In a limited way, the US government is applying a “propagule pressure approach” in a variety of prevention policy contexts aimed at minimizing the impact of harmful organisms. However, there are also readily apparent opportunities for enacting propagule pressure-based measures to fill current gaps in invasive species prevention and control at national, state, and local levels. An explicit focus on propagule pressure-based policies could substantially increase the effectiveness of US efforts to prevent the introduction of invasive species through by intentional and unintentional introductions.

Bioinvasions, bioterrorism, and biosecurity

Despite their high profile and potentially devastating consequences, bioterrorist acts are relatively unpredictable, rare, and thus far small-scale events. In contrast, biological invasions are occurring daily in the US and have significant impacts on human health, agriculture, infrastructure, and the environment, yet they receive far less attention and fewer resources. Scientists and the US government must work together to implement a comprehensive approach to biosecurity that addresses not only bioterrorism, but also the more common incursions of invasive alien species. This approach should also address the potential for the deliberate use of invasive alien species as agents of bioterrorism. To achieve these goals, it will be necessary for the relevant government institutions to acknowledge and include prevention, early detection, and rapid response to species incursions as central mission themes. In addition, the scientific community, industry, and the public must work together to ensure that the neces...

Biosecurity from the ecologist's perspective: developing a more comprehensive approach

National planning for biological security should encompass more than just protection against biological weapons. Global forces such as the introduction and spread of invasive species (including emerging infectious diseases), in conjunction with population growth, climate change and sea-level rise, also constitute threats to security. These linked biological and abiotic phenomena make the United States and other countries less secure by degrading ecosystems and ecosystem services, posing risks to human health and safety, and altering patterns of agriculture, settlement, migration and economic opportunity. Several other countries already use a more comprehensive definition of biosecurity than the USA, one that includes biological threats to the environment, the economy, and human health and wellbeing. We assert that an expanded definition of biosecurity is necessary in a world undergoing rapid change due to altered climate, growing population and increased rates of trade, transport and travel.