There has not been a comprehensive view of the field of plant reintroductions since Falk and Holsinger 1991. That volume marked a crystallization of the research and policy agendas for plant conservation in this country, and since that time there has been increasing activity on many fronts. This volume's articles provide an invaluable compilation of references to the field, as well as careful reporting and discussion of the works drawn from.
The book has four parts: [I] The Environmental and Policy Context for reintroduction; [2] the Biology of Rare Plant Reintroduction; [3] Reintroduction in a Mitigation Context [4] Case Studies. In each of the first three parts, there is a FOCUS article providing a case study illuminating the issues of that part. Case studies include reintroduction of rare plants in Hawaii, a reintroduction program for Pinus torreyana, and several other projects in various habitats from bogs to deserts.
Part 1, The, Environmental and Policy Context for reintroduction, focuses primarily on what is known about the causes of plant rarity, and on the climate and landscape alterations currently affecting species' distribution and abundance, including global warming, habitat destruction, and habitat fragmentation. Chapter 4, on The Regulatory and Policy Context, summarizes the relevant policies of the US Fish and Wildlife Service, and the Endangered Species Act.
Part 2, The Biology of Rare Plant Reintroduction, is a very rich survey of the relevant conservation science. Unlike the articles in collections like Falk and Holsinger, or Fiedler & Jain, the chapters work from a unified perspective, discussing the relevant demographic, genetic, and logistical considerations from a very "applied" point of view. Thus, each of these elements in plant rarity and in reintroduction success is discussed as it specifically touches on Defining Success (Pavlik, Ch. 6), Selecting Reintroduction Sites (Fiedler and Lavin, Ch 7), Designing populations (Guerrant Ch 7), Lessons from Ecological Theory: dispersal, establishment, and population structure (Primack, Ch. 8) and Monitoring (Sutter, Ch 9). In thinking about my own experimental work, I found Gueffant's article on Designing Populations both a resource and a challenge, because his treatment explores the implications for a reintroduction design of life-history characteristics, the species' autecology, and the relevance of specific horticultural techniques under various conditions. Guerrant and Primack each provide useful new dimensions in their reviews of their subjects, Guerrant by creating a dialogue between the empirical biological considerations that he centers on, and the power of models to provide quantitative conjecture and possible generalizations which can promote both further research and foster generalizations in the midstof arapid accumulation of data. Primack draws from a wide range of literature, including animal reintroductions, which provide a contrast group of cases which raise useful questions, at least by analogy, for plant reintroductions: what are the comparative values of gathered vs. propagated material for reintroductions? How closely should (can!) reintroductions mimic natural colonization and dispersal events?
Part 3 of the book discusses reintroductions as part of mitigation efforts. Here, the articles show, both from the point of view of policy and of implementation, the complex interactions that arise in the partnerships of science, government, and business. The alliances are usually uneasy and as the extended discussion of mitigation efforts in California shows (Chapter 13, Howland "Translocation as a Mitigation Strategy: Lessons from California), all the scientific insight so far accumulated gets filtered, deflected, and occasionally employed in such mitigations. Despite the drumbeat of consensus that has gathered in the past decade about the need for careful quantitative design and monitoring of mitigation plans, both to improve success and to provide more knowledge about the reintroduction process.
Part Four, Case Studies, gives seven brief profiles of reintroduction projects, including information about the conservation status and biology of each species, the design of the reintroduction, criteria for success, policy considerations, and at least initial results. These are then followed by a concluding chapter, Part V, Guidelines for developing a rare plant reintroduction plan, which puts t e se ence and experience presented by the rest of the book into a concise, action-oriented form.
I can hardly fault the book on any score; lingering dissatisfactions come from the early state of the field. So many questions remain open that only time and lots of experience can answer: how strong are our generalizations about the biology of rare plants? What are the relative values of in situ protection of extant populations versus reintroduction or other propagation of rare species? How do we incorporate the best new science, say, in population genetics or demography, into plant conservation, when the science itself is so new as to be quite speculative (a case in point being the need - or not - to consider metapopulation structure in a reintroduction plan)? This volume, taken together with the previous survey by Falk and Holsinger, provides an invaluable reference and also portrayal of the state of the art; I look forward to the next installment, a few years down the road. - Brian Drayton, Dept. of Biology, Boston University, and TERC, Cambridge MA
Literature Cited
Falk, D. and K. Holsinger. 1991. Genetics and conservation of rare plants. Oxford University Press, New York
Fiedler, P. and S. Jain. 1992. Conservation Biology. New York: Chapman-Hall.