Keeping the door open: protecting biological corridors with existing federal statutes.

• Author: Thompson, Mark R.

1. INTRODUCTION A. Fragmentation and Extinction 1. Stochastic Threats 2. Inbreeding Depression 3. Disruption of Population Dynamics B. Hopes for a Remedy 1. Biological Corridors 2. Challenges on the Ground 3. The Need for Speed II. EXISTING FEDERAL LAW AS A TOOL FOR PROTECTING CORRIDORS A. Plan-Oriented Statutes 1. National Forest Management Act (NFMA) a. Viability b. Viability on a Forest-Wide Scale c. Viability on a Range-Wide Scale d. New Regulations 2. Federal Land Policy and Management Art (FLPMA) a. Interdisciplinary Approach b. Areas of Critical Environmental Concern c. FLPMA's Utility 3. Sharpening the Tool of Plan-Oriented Statutes B. National Environmental Policy Act (NEPA) 1. NEPA's Framework 2. NEPA's Usefulness a. Arguing the Action "Significantly Affects" the Environment b. Arguing an EIS Is Inadequate C. Endangered Species Act (ESA) 1. Jeopardy Clause a. White Pine Project b. Action Area 2. The Take Prohibition 3. Habitat Protection Provisions of the ESA a. Critical Habitat Designation b. Recovery Plans III. KEEPING THE DOOR OPEN I. INTRODUCTION

   A Canada lynx (Lynx canadensis) may travel hundreds of miles before funding a mate. (1) Black bears (Ursus americanus), having learned of a source of food over fifty miles away, may return to it year after year. (2) A young timber wolf (Canis lupus) may even move more than five hundred miles from its birthplace during its life. (3) Consider for a moment the challenges such animals might face. A few are obvious--highways, subdivisions, increasingly diminished forests, run-ins with humans, and the effects of development in general. Such encounters present more than a mere inconvenience, however. For many species, they signal a spiral toward extinction.

   1. Fragmentation and Extinction

      As the human population grows, extracts resources, and develops the landscape, it cuts vital wildlife habitat to pieces. Once contiguous habitats become isolated "islands," (4) effectively trapping wildlife within shrinking confines. Conservation biologists point to this process, habitat fragmentation, as one of the leading causes of extinction. (5) Habitat fragmentation afflicts not only wide-ranging animals, but virtually all species, down to the endangered Preble's meadow jumping mouse (Zapus hudsonius preblei). (6) Additionally, its effects are becoming apparent even in out largest wildlife reserves. (7)

      Three occurrences characterize habitat fragmentation: a loss of overall habitat in an area, a reduction in the size of remaining blocks of habitat, and increased isolation of those blocks. (8) As these characteristics increase in habitat patches, wildlife populations face an increased likelihood of extinction for several reasons besides simple prevention of migration or lack of access to food sources. (9)

      1. Stochastic Threats

         First, isolated populations are more likely to go extinct due to stochastic threats, (10) or in other words, chance. (11) Species are always subject to disturbances, such as predation, random variation in birth rates, changes in amounts of food supply, natural catastrophes, and disease. (12) If a population is large, it is likely that at least some of its members will survive such disturbances and allow the community to persist. (13) Conversely, if a population is small, there is an increased likelihood that a disturbance will exterminate the entire population. In other words, when a large interconnected population is divided into smaller isolated groups, it becomes increasingly likely that the entire population will eventually die out due to disturbances within each isolated group. (14)

      2. Inbreeding Depression

         Second, as wildlife populations become increasingly isolated through fragmentation, the number of potential mates decreases for every individual, which can result in higher rates of inbreeding. Where inbreeding occurs, the genetic makeup of each member of a breeding pair is more similar than it would be if individuals were matched at random. (15) This leads to increased homozygosity, where offspring have a higher chance of exhibiting detrimental genes that may have been unexpressed in either parent. (16) In general, inbreeding and the resultant loss of genetic variation have "harmful effects on development, survival, and growth rate" for species. (17) This effect, inbreeding depression, increases the chances of extinction in a population. (18)

      3. Disruption of Population Dynamics

         Finally, isolation generally disrupts natural population dynamics. Many populations of species naturally exist in dispersed, yet connected subpopulations. (19) Among these subpopulations, some act as "sinks," meaning that they tend to rely on the introduction of new individuals for continued survival. (20) Conversely, some subpopulations act as sources, producing a surplus of individuals. Source subpopulations may maintain a species' existence by "sending out a stream of emigrants" that may supplement a sink population, enter other existing populations, or found new subpopulations. (21) When habitat fragmentation isolates populations from one another, these dynamics are disrupted, and populations become less stable.

   2. Hopes for a Remedy

      1. Biological Corridors

         Common sense may suggest that if fragmentation is a major cause of extinction, simply ensuring that habitats remain connected may save species. With that hypothesis, conservation biologists have focused a great deal of study on biological corridors. (22)

         A biological or wildlife corridor is a strip of habitat that is suitable for wildlife passage and generally connects two or more larger habitats. (23) Corridors may have a variety of origins. For example, streams and rivers, with their attendant riparian vegetation, may serve as corridors. (24) Habitat remnants within otherwise disturbed areas, such as stands of timber that remain within a logging zone, may serve a corridor function. (25) Human activities, such as the creation of a greenbelt, may form a corridor. Corridors may even develop from something as simple as a fencerow that harbors weeds within a bare field. (26)

         Experimentation shows that at least to some extent, corridors allow certain populations of species to persist when those populations might otherwise face extinction due to fragmentation. (27) The theory is that corridors reduce extinction rates through several methods: They allow for genetic exchange among adjoining populations, thus avoiding or decreasing inbreeding depression; (28) they provide a mechanism through which a species can colonize new habitat or recolonize habitats in which a population extinction event occurred; (29) and they provide an avenue for emigrating and commingling, decreasing the occurrences of extinction by stochastic threats. (30)

      2. Challenges on the Ground

         Not surprisingly, many important biological corridors exist on federal lands such as national forests, state parks, and general public lands. While this fact may generate hope that these corridors can be protected through careful planning and government protections, this is not always the result. Agency actions, such as resource extraction, road building, and management practices often threaten these corridors with destruction. (31) Thus, although biological corridors represent a pragmatic, logical, and real defense against extinction, ensuring their protection requires an active effort, often fraught with conflict and complications. Those seeking to preserve corridors against detrimental agency action quickly recognize a scarcity of laws well-tailored to corridor protection. Potential plaintiffs and activists thus lack a solid legal platform from which to mount arguments for corridor protection, and although habitat connectivity is often a motivating concern behind litigation, the issue of corridor protection is rarely front and center. (32) Certainly, to some extent this lack of focused law has enabled agencies to bypass consideration of corridor issues when making management decisions.

         Motivated partially by this lack of tailored legal protections for corridors, several groups have launched campaigns for ecosystem-level protection plans in North America. (33) These groups seek to implement protections for important corridors through various means, including landmark legislative proposals. (34) However, actual implementation of any of the plans is far from certain, (35) and unless and until these groups succeed (36) most biological corridors remain vulnerable to destruction.

      3. The Need for Speed

         As time passes, fragmentation continues and the urgency of protecting corridors only increases. (37) Wildlife managers estimate, for example, that without active protection development and resource extraction will destroy critical grizzly bear (Ursus arctos horribilis) corridors in the Northern Rockies within the next ten to fifteen years. (38) Because no comprehensive legislative-type protections for corridors appear imminent, it is extremely important to consider what tools are available now for addressing the problem of corridor destruction.

         This Comment evaluates four major federal environmental statutes to determine how they can operate as tools to protect corridors on federal lands. (39) First, the Comment analyzes two planning-oriented environmental statutes: the National Forest Management Act (40) and the Federal Land Policy and Management Act. (41) Next, the Comment analyzes the National Environmental Policy Act, (42) and finally, the Endangered Species Act. (43) The Comment concludes that although each of these statutes contains significant weaknesses, the statutes represent valuable tools that parties can employ in order to keep the door to survival open for species through protecting corridors.

2. EXISTING FEDERAL LAW AS A TOOL FOR PROTECTING CORRIDORS

   1. Plan-Oriented Statutes

      1. National Forest Management Act (NFMA)

         The National Forest Management Act (NFMA) imposes substantive controls on land management within the National Forest System. It...