Conservation and Toxicology: Integrating the Disciplines*

Global warming, ultraviolet radiation, and acid rain are large-scale environmental problems that concern conservation biologists. They are caused, to varying degrees, by human-generated pollution and consequently are also a concern of environmental toxicologists. These problems seem to be the major areas of overlap between conservation biologists and environmental toxicologists, overlap that is probably the result of two factors. First, there is a general tendency for scientists to specialize and fail to take advantage of the ideas and information in other fields. Second, environmental toxicology and conservation biology focus on different levels of biological organization. We believe that it is time for conservation biologists and environmental toxicologists to become more aware of their shared goals. Consider the statement of goals printed in the major journal of each field. In Conservation Biology they are stated as “. to help develop the scientific and technical means for the protection, maintenance, and restoration of life on this planet—its species, its ecological and evolutionary processes, and its particular and total environment. ” Environmental Toxicology and Chemistry states its mission as “. a forum for professionals in academia, industry, government, and other segments of society involved in the use, protection, and management of the environment for the enhancement of ecological health and human welfare. ” These statements are quite similar, yet the mention of conservation biology by environmental toxicologists or of environmental toxicology by conservation biologists is rare. In the past 2 volumes of Conservation Biology , only 8 articles of 394 (2%) discussed pollutant-related environmental damage. Likewise, only 56 articles of 560 (10%) in Environmental Toxicology and Chemistry discussed conservation issues relating to the effects of environmental contamination. These percentages are based on a liberal survey of the literature wherein an article need only allude to the conservation implications of a toxicological study or the existence of a toxicological effect on conservation issues. For example, mention of global warming in a conservation article even without the mention of the causes of global warming was grounds for inclusion in the totals. One of the major interests of conservation biologists is conducting population viability analyses (PVAs) to determine the probability of extinction of populations or species. Essential to calculating extinction risk is the tenet that larger populations are at a lower risk of extinction (Pimm et al. 1988). Shaffer (1987) pointed out that populations affected by environmental uncertainty and catastrophe require greater minimum population sizes to persist. Although conservation biologists typically are concerned with factors such as habitat destruction and fragmentation or the introduction of exotic species, chemical contaminants can cause major extinction events or act subtly in concert with other factors to compound the probability of extinction. A large-scale catastrophe such as an oil spill, nuclear accident, or untreated effluent release can cause immediate loss of entire populations. Although they are rare, accounting for these events in PVAs and endangered species management can be done effectively. The southern sea otter recovery team included toxicologists and conservation biologists who developed a PVA that included the probability of a large oil spill affecting the population size of otters off the coast of California (Ralls et al. 1996). Including more subtle effects of contaminants in PVAs is possible and can take many forms. Of particular im*A version of this paper appears concurrently as a letter in the October issue of Environmental Toxicology and Chemistry (volume 18).