Freshwater unionid mussels are one of the most rapidly declining components of North American freshwater biodiversity. Although they are of ecological and economic significance, we are faced with a considerable deficit in our knowledge of unionid life history and ecology. In particular, growth rates and longevity have been approached using erroneous techniques. Consequently, much of conventional management for these declining species may be inadequate. This thesis explores a new method for estimating age in unionid mussels. Through applying an inversion of the von Bertalanffy growth equation to mark and recapture-inferred growth rates, true ages of unionid mussels were estimated. Apparently, mussels may reach ages much older than previously expected. With ages that may exceed a century in some populations, freshwater mussels may be among the oldest living creatures in the world. The extreme age and slow growth of these bivalves may be, in part, at the root of their failure to support sustainable fisheries. Although freshwater mussel populations in the United States have been intensively exploited for various economic interests for over 100 years, harvests have been volatile and many mussel populations presently seem commercially unviable. The extreme age, slow growth, and reproductive ecology of these mollusks are compatible with an Allee effect whereby exploitation may rapidly lead to decreased per capita reproduction and even extinction. These aspects of mussel life history and reproductive ecology parallel those of many classically overexploited species and the Allee effect may be more common than previously expected in exploited populations.

All those who think that bivalves are boring are in the best company. Karl von Frisch is reported to have turned the pages more quickly in texts where bivalves were treated because, according to him, they literally lack any behaviour. The fact that they can filtrate huge amounts of water, burrow into the sedi ment, actively swim, drill holes into rocks and boats or detect shadows with the aid of pretty blue eyes located on the rim of their mantle obviously left v. Frisch unimpressed. Why, then, a book on the large freshwater mussels (Naiads or Unionoida), which on first sight are much less spectacular than the marine ones? The main reason is that they are keepers of secrets which they reveal only on close and careful inspection. This is not only true for the pearls some species produce and which over centuries have contributed to the treasures of bishops and kings, but particularly for their ecology: their life cycles are linked with those of fishes, some can occur in incredible densities and some can live for more than 100 years. Thus, the presence or absence of naiads in a lake or stream has manifold implications.

Pearly mussels (Unionoidea) live in lakes, rivers, and streams around the world. These bivalves play important roles in freshwater ecosystems and were once both culturally and economically valuable as sources of food, pearls, and mother-of-pearl. Today, however, hundreds of species of these mussels are extinct or endangered. David L. Strayer provides a critical synthesis of the factors that control the distribution and abundance of pearly mussels. Using empirical analyses and models, he assesses the effects of dispersal, habitat quality, availability of fish hosts, adequate food, predators, and parasites. He also addresses conservation issues that apply to other inhabitants of fresh waters around the globe and other pressing issues in contemporary ecology.

Freshwater mussels are declining rapidly worldwide. Propagation has the potential to restore numbers of these remarkable organisms, preventing extinction of rare species and maintaining the many benefits that they bring to aquatic ecosystems. Written by practitioners with firsthand experience of propagation programs, this practical book is a thorough guide to the subject, taking readers through the process from start to finish. The latest propagation and culture techniques are explored as readers follow freshwater mussels through their amazing and complex life cycle. Topics covered include the basics of building a culture facility, collecting and maintaining brood stock, collecting host species, infesting host species with larval mussels, collecting and culturing juvenile mussels, releasing juveniles to the wild, and post-release monitoring. This will be valuable reading for any biologist interested in the conservation of freshwater mussel populations.

This well-illustrated book highlights freshwater mussels' fabulous diversity, amazing array of often bizarre ecological adaptations and their dire conservation plight. Summarizing and synthesizing historical and contemporary information as well as original research and analysis, the book describes the diverse array of mussel life history strategies and builds a cohesive narrative culminating in the development of explicit frameworks to explain pervasive patterns in mussel ecology. The fascinating and colorful role of mussels in human society is also described in detail, including the little-known pearl button industry of the early 1900s and the wild and often violent shell harvest of the 1990s. The final chapter details humans' efforts to save these fascinating animals and gives a prognosis for the future of the North American fauna. The book provides the first comprehensive review of mussel ecology and conservation for scientists, natural resource professionals, students and natural history enthusiasts.