Interior Secretary Bruce Babbitt unveiled an ambitious plan yesterday to protect 68 threatened and endangered species living in southern Florida. Babbitt said the government hopes the plan will become a model for approaching species protection on a comprehensive, regional, multi-species level rather than with a piecemeal approach. Under the plan, the feds would work with developers and local governments to set aside habitats for multiple species before construction projects begin; then, in most cases, developers would not be obligated to protect endangered species on land designated for development. Some enviros criticized the plan for being short on specifics.