Chapter Ten - Parasites as Biological Tags

Abstract

This chapter provides a guide for parasitologists and fishery biologists to the use of parasites as biological tags for stock identification of marine fish. Parasite tags have certain advantages over other methods of stock identification, but they also have their limitations, so we strongly recommend an interdisciplinary approach in which the results from different methods are compared and used to complement one another. Some biological features to consider in the selection of a good tag parasite are described here, but these should be regarded as guidelines rather than strict criteria. Two different approaches to the use of parasites as biological tags are described, one in which a large number of fish are examined for a small number of parasite taxa and the other in which entire parasite assemblages are analyzed using multivariate statistical methods. Example case studies are given, which are representative of the two approaches. The statistical methods applied to parasite infection data tag studies are described and discussed, with references to studies in which they have been used. Recommendations are given for the collection of hosts and parasites to ensure that parasites are collected in the best possible condition, and methods for the preparation of parasites for examination are described. Parasite groups requiring special attention in their collection and preparation are highlighted, and publications giving identification keys to different taxonomic groups of parasites are provided. There is also a section dealing with the interpretation of results in terms of stock identification.