Cover

pdf iconDownload PDF

pp. 1-1

Title Page, Copyright

pdf iconDownload PDF

pp. 2-5

Contents

pdf iconDownload PDF

pp. v-vi

read more

Preface

pdf iconDownload PDF

pp. vii-x

I wrote this little book to try to solve a specific problem and at least shed some light on, if not solve, a very general problem in ecology. The specific problem is understanding how ecological factors determine the distribution and abundance of pearly mussels (Unionoidea). ...

Part One: The Laboratory

pdf iconDownload PDF

pp. 1-2

read more

1. The Model as Monster

pdf iconDownload PDF

pp. 3-8

One of the most enduring popular images of science is that of the cinematic mad scientist, scouring a graveyard for body parts from which to build a monster. Dr. Frankenstein is faced with two formidable tasks. First, he and his hunchbacked assistant must gather all of the pieces needed to build a living monster (usually while evading the local constabulary). ...

read more

2. The Case of Pearly Mussels

pdf iconDownload PDF

pp. 9-22

Pearly mussels of the superfamily Unionoidea (including the families Unionidae, Margaritiferidae, and Hyriidae) are common and widespread in rivers, streams, lakes, and ponds around the world, living on all continents except Antarctica. They can form locally dense populations of >100 animals/m2 (Fig. 42), ...

Part Two: The Monster’s Parts

pdf iconDownload PDF

pp. 23-24

read more

3. Dispersal

pdf iconDownload PDF

pp. 25-42

In the next five sections of the book I will review the five processes— dispersal, habitat, fish hosts, food, and enemies—that I think have the potential to control the distribution and abundance of unionoids. In each of these sections, I will briefly review the state of knowledge about the process, ...

read more

4. Habitat

pdf iconDownload PDF

pp. 43-64

Habitat is probably the first factor to have been thought of as limiting mussel populations. By the time that a scientific literature on unionoid ecology began to develop in the late 19th and early 20th centuries, it was already widely stated that different species of mussels required different habitats ...

read more

5. Hosts

pdf iconDownload PDF

pp. 65-86

The larvae of most unionoids are parasitic on fish, so it is reasonable to suspect that the distribution and abundance of host fish might be an important factor in limiting unionoid populations. Before discussing the use of fish by unionoids, though, it is worth briefly considering the exceptions to the basic life cycle, ...

read more

6. Food

pdf iconDownload PDF

pp. 87-104

The quality and quantity of food are often regarded as among the primary factors that regulate the distribution and abundance of organisms in nature. It is thus curious that little attention has been given to the possibility that food might limit the distribution or abundance of unionoid mussels. ...

read more

7. Enemies

pdf iconDownload PDF

pp. 105-112

Predation, parasitism, and disease are often thought to limit animal populations but these factors have not been thoroughly investigated for unionoids. We can list some of the predators and parasites that affect unionoids and we know something about the selectivity and feeding rates of a few predators. ...

read more

8. Implications for Conservation

pdf iconDownload PDF

pp. 113-118

It is worth emphasizing that human activities have had major effects on all five of the classes of factors that control unionoid populations, and thus have had large, varied impacts on unionoid distribution and abundance (Fig. 45). Model and empirical analyses (Figs. 11, 12, 15) suggest that the barriers that humans have spread throughout many river systems ...

Part Three: Making the Monster Walk

pdf iconDownload PDF

pp. 119-120

read more

9. Three Models for Mussel Ecology

pdf iconDownload PDF

pp. 121-142

It seems clear that unionoid distribution and abundance is controlled by multiple factors, and that we therefore need some sort of plan for building a working theory that includes the effects of these multiple factors. It is not just unionoid ecology that needs a Dr. Frankenstein; many ecological variables are simultaneously controlled by multiple factors. ...

read more

10. Is a Comprehensive Model Possible?

pdf iconDownload PDF

pp. 143-156

I do not believe that any of the three popular approaches to integration, as currently practiced by ecologists, is likely to lead to a satisfactory predictive understanding of unionoid distribution and abundance. As I suggested earlier (and will discuss further below), it is likely that a simple Liebigian approach will be satisfactory only when applied over limited domains. ...

Literature Cited

pdf iconDownload PDF

pp. 157-198

Index

pdf iconDownload PDF

pp. 199-204

Production Notes

pdf iconDownload PDF

pp. 216-217