RECLAMATION OF PONDS, LAKES, AND STREAMS WITH FISH TOXICANTS: A REVIEW

PREPARATION OF THIS PAPER

This critical review of the world-wide use of toxicants in the reclamation of inland fishing waters is based on a review of the literature and a widely circulated questionnaire. It was prepared for FAO by the Fish Control Laboratories, U.S. Fish and Wildlife Service, Bureau of Sport Fisheries and Wildlife, Division of Fishery Research. This study was carried out by Dr. Robert E. Lennon, Dr. Joseph B. Hunn and Mrs. Rosalie A. Schnick and Dr. Ralph M. Burress.

The views expressed in this paper are those of the authors and not necessarily of the Food and Agriculture Organization of the United Nations.

FOREWORD

The Food and Agriculture Organization of the United Nations commissioned this review on the chemical control of undesirable fish so that an evaluation might be made on its effectiveness in fishery management. We commend FAO for its foresight in initiating the review, and we were pleased with the opportunity to compile it. The review is timely because of world-wide concern on the part of health authorities with respect to the persistence and chronic damages by pesticides in the environment. The use of many of the so-called “hard” pesticides is now being curtailed or prohibited by some regulatory agencies, and other pesticides are coming under increasingly critical scrutiny.

We urge that fishery personnel participate in an objective, ecologically based evaluation of fish toxicants and reclamation projects. Our use of toxicants should be restricted to instances of demonstrated need where practical alternatives are lacking. The toxicants employed should be specific to fish and proven safe to wildlife, livestock, and man. In every application, the well-being of the environment must take precedence over short-term economy or convenience. We believe that fish toxicants play an important role in fishery management, but we obviously must exercise greater judgement and competency in selecting and applying toxicants, and in assessing results than in the past.

Because of the scope of this review, the sections were assigned among reviewers as follows:

Section 2:	Fish production ponds and farm and ranch ponds -- Mr. Ralph M. Burress
Section 3:	Lakes -- Dr. Joseph B. Hunn
Section 4:	Streams -- Dr. Robert E. Lennon
Section 6:	Results of a world-wide questionnaire on reclamation -- Mrs. Rosalie A. Schnick

We gratefully acknowledge the help of many persons who provided literature or suggested sources of information. In particular, we thank the Library Reference Service, Denver Public Library, and Charles M. Larsen, Inland Fishery Resources Branch, FAO, for repeated assistance in the review.

Moreover, we recognize faults and gaps in the review. We respectfully request that readers bring discrepancies and omissions to our attention.

Hyperlinks to non-FAO Internet sites do not imply any official endorsement of or responsibility for the opinions, ideas, data or products presented at these locations, or guarantee the validity of the information provided. The sole purpose of links to non-FAO sites is to indicate further information available on related topics.

CONTENTS

ABSTRACT

The Food and Agriculture Organization of the United Nations commissioned the U.S. Bureau of Sport Fisheries and Wildlife to prepare a review of literature on the reclamation of ponds, lakes, and streams with fish toxicants. Total or partial reclamation of small ponds, especially fish production ponds, with general or selective toxicants is a very common practice. The eradication of undesirable fishes from public lakes and streams began over 60 years ago, but accelerated within the past two decades as wild waters increasingly required fish management and as improved toxicants became available. Toxicants such as the organochlorines and organophosphates, borrowed from agriculture, are being replaced with controls that are more specific to fish or more appropriately formulated for aquatic application. Formulations of rotenone and antimycin are the most used, general fish toxicants in the United States; TFM is a successful, selective toxicant for larval sea lampreys in tributaries to the Great Lakes; and Squoxin is in advanced stages of development as a selective toxicant for squawfishes in salmonid streams on the west coast of North America.

The review of literature and a widely circulated questionnaire indicate that 27 countries, in addition to the United States, and Canada, have used or are using fish toxicants for the control of undesirable fishes. Indicated, too, is the need for much research on all aspects of reclamation -- on the biology of target fishes; on alternatives to chemical control; on safe, effective, and non-persistent toxicants; on formulations and dispensing apparatus to reach and kill target fishes with the least possible contamination of the environment; on controls that may be integrated with toxicants to enhance reclamations; and on methods and equipment for pre- and Post-treatment surveys and evaluations.