Migration conservation: a view from above.

• Author: Fischman, Robert L.
• Position: Symposium Essay

1. The Importance of Animal Migration Conservation II. The Symposium Articles A. Scientific Research Agenda B. Law and Policy Reform C. Collaboration Case Studies III. Conclusion I. THE IMPORTANCE OF ANIMAL MIGRATION CONSERVATION

   Animal migrations are widely appreciated as among the most awe-inspiring spectacles of nature. Yet, they are hardly recognized in the law of biodiversity protection. Migration as a phenomenon, and the migratory species of all taxa that display this fascinating behavior, are disappearing all over the world with attendant loss of ecosystem functions and social values. The decline of migrations is a sadly familiar tale in conservation literature: compelling evidence reveals that large-scale migrations are succumbing to the pressures of habitat modification, prey disappearance, hunting pressures, barriers to movement, and pollution. The diverse animals that migrate, including butterflies, salmon, sea turtles, bats, and songbirds, are struggling to continue a tenuous yet important adaptation.

   Extinction prevention programs employ population thresholds that may be inadequate to preserve migratory behavior. So, we may retain bison, whooping cranes, and salmon, but lose the suite of benefits migrations provide. Besides the subjective human experience, animal migrations cycle nutrients and facilitate other ecological processes. Many promote ecosystem resilience that enhances the ability of natural systems to recover from disturbances and stresses, including some manifestations of climate change. (1)

   There are two primary reasons why conservation of migratory species does not always preserve actual migrations. The first is habitat loss or migration route barriers that thwart movement. This is why connectivity linking breeding sites, travel paths, wintering areas, and key sources of food across landscapes is a key challenge for conserving animal migrations. Connectivity is also critical for effective adaptation to climate change, which will spur species to disperse into new regions. (2) In that respect, successful efforts to maintain animal migrations may create templates for improving ecological resilience as climate change accelerates. One important theme of this symposium is that conserving migrations will offer lessons applicable to the problem of climate change adaptation.

   The second reason is that some species require populations well above minimum-viable, survival levels in order to engage in migration. (3) The rationale for preserving migratory behavior, therefore, must go beyond the rationale of preventing extinction. Keeping common species common is a traditional justification for conservation actions, particularly for programs aimed at sustained yield. (4) Maintaining abundant migrations forestalls the difficult triage decisions of recovering imperiled species and provides greater ecological services and resilience to landscapes. Abundant migrations are increasingly rare. So, paradoxically, the conventional motivations for preserving wondrous but rare aspects of nature would also support some of the migration conservation agenda.

   Suppose that law and policy were to wholeheartedly embrace a conservation goal of maintaining ecological functions and processes to supplement the ecological elements (e.g., imperiled species, coastal wetlands) on which existing programs focus. The conservation challenge of protecting all migrations would nevertheless be insurmountable. Yet the research reflected in this symposium can be used to set priorities. Generally, resources should be devoted to two kinds of migrations: 1) those involving sufficiently large populations as to be important shapers of ecosystems; and 2) motivators of conservation among the public.

   It is a truth universally acknowledged that complex conservation challenges require collaboration. (5) However, as with Jane Austen's aphorism, confident declarations often belie vexing difficulties in their execution. Management of animal migrations raises two kinds of collaboration challenges. First, it requires scientists, lawyers, policymakers, and resource managers to work together across disciplinary boundaries. Too often, for instance, the research agenda of natural scientists fails to match up with the information needs of resource managers. Second, conservation of roaming creatures requires coordination across governmental boundaries, administrative jurisdictions, and property lines.

   This symposium on animal migration conservation makes important contributions to promoting both kinds of collaboration. Indeed, this collection of articles may serve as a model for addressing a wide range of collaboration challenges. Animal migration conservation raises all of the complex difficulties that characterize what is special about environmental law (6) and that inspired resource managers to adopt ecosystem management. (7) Better understanding the challenges of and innovations in migration protection will also inform the full spectrum of large-scale conservation problems raised by climate change.

   Of course, the basis for conservation policy should be solid scientific research. But, despite recent advances in technology, the migratory pathways and winter ranges of many species remain unknown. This raises the stakes for designing standards and programs that can be effective even without precise information. Waiting for better information is a chronic delay tactic in environmental law, and often exacerbates a problem as resource scarcity increases and degrees of management freedom diminish.

   Law has always tailored its approaches in response to different information challenges. The common law of property responded to the "secret, occult and concealed" movements of groundwater by imposing a rule of capture because any other rule would mire in "hopeless uncertainty." (8) In the past half-century, improved monitoring and modeling substantially sharpened predictions of groundwater movement. As a result, many states have shifted to a different rule requiring equitable sharing of groundwater. (9)

   We may well be on the cusp of a similar change in migration conservation. Longstanding mysteries of animal movement are yielding to tracking and mapping innovations. In 1768, Samuel Johnson noted to Boswell that swallows wintered under water. (10) Despite the progress made in the subsequent quarter millennium, for most migrations our conservation policies must be robust to uncertainties about the details of the migratory behavior. We must simultaneously pursue research to pin down the spatial, temporal, and demographic details of migrations while we reform conservation policy to make better guesses about practices that will sustain migratory behavior. While scientists work to understand migrations in greater detail, law and policy must...