Otolith Removal and Preparation
for Microstructural Examination: A Users Manual (1991)

by

D.H. Secor, J.M. Dean, and E.H. Laban



Otolith microstructural studies exist for over 50 families and 135 species of fish and aquid. A review of more than 200 investigations showed that a wide variety of techniques have beeb used in otolith microstructure studies. We foresaw the need of a manual on otolith preparation as microstructure studies become routine in life history investigations. The purpose of our manual is to:

  1. Permit and encourage fish biologists and fishery scientists to include otolith microstructural analysis in their investigations,

  2. List all techniques, materials, and equipment necessary for large-scale aging studies on young fishes, and

  3. Provide a basis for standardization of protocols and techniques

To accomplish these aims, detailed methods are provided on otolith removal, cleaning, storage, sectioning, polishing, and etching. We emphasize that there are many alternative methods to those described in the manual. To facilitate review of other laboratories' techniques, tables are provided which sort out published methods by author and species.


ENTIRE MANUAL [Warning - This is a 34.5 Mb Document; will open in a new window]


INTRODUCTION: Title Page / Foreward / Preface / Table of Contents [800 Kb; will open in a new window]

CHAPTER ONE: History and Background [512 Kb; will open in a new window]

  • Panella's Rosetta Stone
  • Manual objectives
  • How to use this manual

CHAPTER TWO: Position and Morphology of Otoliths in Fishes [1.9 Mb; will open in a new window]

  • Otolith and vestibular structure
  • Variation in otolith morphology
  • Anatomy of the auditory capsule

CHAPTER THREE: Protocol Decisions [1.3 Mb; will open in a new window]

  • Which otolith and section?
  • Which mounting and embedding media?
  • Which polishing technique?

CHAPTER FOUR: Removal Techniques [3.1 Mb; will open in a new window]

  • Otoliths greater than 300 µm: Macroscopic techniques
  • Otoliths less than 300 µm: Microscopic techniques

CHAPTER FIVE: Cleaning, Handling, and Storage [1.0 Mb; will open in a new window]

  • Otoliths greater than 300 µm
  • Otoliths less than 300 µm

CHAPTER SIX: Section Preparation [5.8 Mb; will open in a new window]

  • Embedding
  • Sectioning
  • General polishing procedure
  • Polishing otoliths less than 300 µm
  • Polishing techniques for species with other otolith morphologies
  • Storage of sections

CHAPTER SEVEN: Etching Sections [2.0 Mb; will open in a new window]

  • Otolith preparation for SEM examination
  • Choice of etching agents

CHAPTER EIGHT: Summary of Laboratory Protocols [1.7 Mb; will open in a new window]

  • Sources of technical error
  • Precision and efficiency
  • Labor and material costs

CHAPTER NINE: Recommendations [416 Kb; will open in a new window]

REFERENCES: Survey of Cited Literature [5.4 Mb; will open in a new window]

APPENDIX I: Systematic Key [8.2 Mb; will open in a new window]

APPENDICES II / III / IV: Supplies / Suppliers (1991) [2.3 Mb; will open in a new window]

UPDATED SOURCES: Supplies / Suppliers (2001) [640 Kb; will open in a new window]


Last updated: 20 October, 2002
Please address any comments, suggestions or questions to: Dave Secor