Guide to the Otoliths of the Bony Fishes of the Northeast Atlantic

About this book

After a careful study of the otoliths, or earstones, of the bony fishes, the present author finds that a great majority of these can be identified to species level. The size of otoliths is also closely correlated to the size of the fish, permitting a reconstruction of the size of a fish with high accuracy from otoliths only. This means that the diet of piscivores can be estimated from otoliths found in stomach contents, faeces or regurgitated pellets. Archaeologists will find it helpful to be able to identify bony fishes to species and size, as will palaeontologists, ichthyologists, ornithologists or people involved in investigations concerning marine mammals.

In this handbook, the first chapter presents the present knowledge about otoliths and the applicability of otoliths in different types of studies. An extensive key to the species presented is followed by a detailed description. The otoliths of the species presented here cover all species found in the faeces of the harbour seal and in pellets from the black cormorant. As many of the species within a fish family have similar otoliths, related species are also presented. Altogether 103 of the most common species in the North East Atlantic and to a lesser extent in the Arctic are described in text, line drawings and 518 scanning micrographs with an object to show the variation of the shape within every species. In association with the description are correlation equations given for the correlation between otolith length and fish length and fish weight.

Several fish groups are, for different reasons, not covered here. These species either occur in very low numbers, or are only occasionally found in the North Sea, or they are unimportant as prey fishes of piscivorous animals. As mainly marine and estuarine species are presented, freshwater groups like the Cypriniformes are also excluded. A third reason for excluding a group is that otoliths in some families are so small that they have no practical applications. The family Synghnathidae is an example of this. In this group, many otoliths are less than one mm long, even in relatively large specimens, and many of these pass a 0.5 mm sieve.

Customer Reviews