Freshwater Fishes of Texas: A Field Guide

Foreword

Foreword I state the obvious in saying this book is for those who want to know how to identify Texas freshwater fishes. In field and laboratory courses I teach students how to identify Texas fishes and about their ecology and management, so naturally I am very glad (and I expect my students will be also) to have this field guide as a formal resource. But, who else would benefit from reading and using this guide? As terrestrial creatures, we rarely look into (let alone enter) the watery world of fishes. Unlike birds, mammals, amphibians, reptiles, flowers, butterflies , and seashells, fish are less accessible to those who collect, photograph, and watch wildlife. Even so, a field guide to fishes is useful to those with a home aquarium or water garden, or who frequent museums and aquaria, and those with a snorkel and mask who travel to systems where fish can readily be seen through clear water. I also recommend this guide to those surrounded by muddy systems, like those near my own house. Once you see our Texas fishes and the maps of their distribution, you will want to read on and will be amazed to learn which fishes are probably living in your own nearby stream, pond, or creek (even though you might need a dip net or small seine to be able to view them up close). I hope that you will then wonder why certain fishes are found only here or there, whereas others seem to be everywhere. Perhaps you will further consider all the biological diversity in our water systems. The photographs themselves are a significant contribution to the published literature on Texas fishes, and they are a very useful complement to the comprehensive and more technical scientific keys used to identify fish to the species level. Moreover, the photographs are combined with drawings and instructions that will help readers to locate various characteristics on a fish, to make certain measurements and counts that together distinguish families and species of fish, and to appreciate the importance and significance of the fish and its role in our water systems. This book also provides the tools to do much more than spot the limited number of fishes that can be readily identified by a few easily seen characters (shape, color, markings, or a limited distribution in river drainages). Lest you take our aquatic biodiversity for granted, turn to the technical instructions in  foreword this guide. Here you can see how a biologist scientifically confirms a fish’s identity . In addition to measuring and counting external features (scales, spines, and fin rays), it may also be necessary to use a microscope or dissection to further examine representatives of a group of similar looking fish for differences in other characteristics, such as length and coiling pattern of the intestine (giving insight into feeding preferences), color of the lining of the body cavity, number and shape of the teeth—not just on their jaws, but also their tongue, roof of their mouth, and bones encircling their throat. Just as birders refer to “LBB’s” (little brown birds that seem at first to all look alike), their counterparts in the fish world are the many small-bodied species among the true minnows (those in the family Cyprinidae). So, do not despair that even with this guide (or even a technical key) you are still unsure of a fish’s identity. Whether you aspire to identify all the fishes in this guide or not, it will help you to realize that biologists entrusted to maintain the natural biodiversity and proper functioning of our water systems must sometimes look beyond scales and skin to verify a fish’s identity. Even ‘experts’ can disagree as to the true identity of a fish, because of the range of natural variation—due to past and ongoing processes of change—contained in the biological diversity among individuals of even a single species. For example, you might be surprised at the range of color patterns exhibited by longear sunfish (Lepomis megalotis), or that even seasoned biologists can make honest mistakes when attempting to identify the common and ubiquitous red shiner (Cyprinella lutrensis), due to its variety of body shapes and colors during its life and across its distribution in so many types of habitat. Also, the young individuals of many fish species look more like each other than they do the adults of their own species, so even the experts will often seek a second opinion. In the comments section...