Marking the first time the agencies have come together to help preserve a declining amphibian species, the U.S. Fish and Wildlife Service, the U.S. Forest Service, and the Oregon Department of Fish and Wildlife yesterday announced a 10-year agreement to study and protect the beleaguered Oregon spotted frog. Historic populations of the red-bellied frog have declined 70 percent, and only one healthy population remains. Loss of habitat and the introduction of non-native species have contributed to the decline of the frog, which is a candidate for listing under the Endangered Species Act. In other Northwest species news, two environmental groups yesterday announced that they will sue the U.S. EPA unless the agency acts immediately to protect threatened and endangered salmon populations from pesticide runoff into streams.