Influence of forest and rangeland management on anadromous fish habitat in Western North America: forest chemicals.
| Authors: | L.A. Norris, H.W. Lorz, S.V. Gregory |
| Year: | 1983 |
| Type: | General Technical Report |
| Station: | Pacific Northwest Research Station |
| DOI: | https://doi.org/10.2737/PNW-GTR-149 |
| Source: | Gen. Tech. Rep. PNW-GTR-149. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 95 p |
Abstract
Herbicides, insecticides, fertilizers, and fire retardants are chemicals used to protect or enhance certain forest resources. Their use may directly affect anadromous fish by exposing them to toxic amounts of the chemical. Indirect effects are also possible through chemically induced alteration of habitat, including direct effects on fish-food organisms.Data on the movement, persistence, and toxicity of chemicals provide a basis for evaluating potential direct effects of chemical use on fish and fish-food organisms. Data are included for seven herbicides (2,4-D, picloram, atrazine, MSMA, fosamine ammonium, glyphosate, and dinoseb), urea fertilizer, and the ammonium-based fire retardants. Comparison of exposures and toxicities of these materials shows their current uses provide a reasonable margin of safety to anadromous fish if direct application to surface waters is avoided.
Much less information is available on indirect effects of chemical use on anadromous fish habitat. The potential effects are known, but few quantitative data exist to evaluate their importance. Apparently, the best way to minimize indirect effects is to minimize the effects of chemicals on all biota in the riparian zone.
Research is needed on the role of buffer strips in reducing entry and impact of forest chemicals in streams, patterns of entry of selected chemicals into streams, instream fate of most forest chemicals, toxicity characteristics of combinations of forest chemicals, the interaction between amount and duration of organism exposure to toxicants, potential latent effects from short-term exposure, effects of forest chemicals on aquatic species under field conditions, and the indirect effects of using forest chemicals on anadromous fish habitat.