Challenges posed by the precautionary principle and accountability in ecological risk assessment

In order to protect the environment, type II errors, e.g. a species is not listed as endangered (H0) when it is in fact endangered (H1), are avoided at the risk of making a type I error. However, it is almost impossible to determine if management efforts have been efficient or if many type II errors have occurred. Applying the precautionary principle to environmental protection without full scientific certainty requires a new academic code for scientists. If we manage ecosystems or bioresources under uncertainty, we need to incorporate new knowledge (accountability) and to change actions with ecosystem states (adaptability). This is called adaptive management. The extinction risk of exploited species under adaptive management is much lower than that under constant exploitation. The revised management procedure (RMP) in whaling and the deer management program in Hokkaido, Japan, share the merit of adaptive management. Under the RMP, the period allowed in considering the extinction risk of the southern hemisphere minke whale is far too long. Population management of over-abundant deer threatened endangered eagles, because of lead contamination from bullets. Although the effect of lead contamination on the extinction risk of eagles was uncertain, the Hokkaido Government prohibited the use of lead bullets in deer hunting. When designing management programs, it is also important to consider cost-benefit measures in the ecological risks. The value of biodiversity is often much higher than the economic benefit from exploiting the bioresource by agriculture, forestry or fisheries. Copyright (C) 2003 John Wiley Sons, Ltd.