IDENTIFICATION 



Identification of ichthyoplankton species beyond those 

 separated during the sorting process was carried out by a 

 separate group of specialists. Ontogenetic stages of fishes are 

 inherently difficult to identify and this is further complicated 

 by the large number and diversity of species which contribute to 

 the ichthyoplankton of the California Current region. Most 

 identifications were accomplished by establishing ontogenetic 

 series on the basis of morphology, meristics, and pigmentation 

 and then identifying these series by relating them to known 

 metamorphic, juvenile, or adult stages with overlapping features 

 (Powles and Markle, 1984) . A total of 153 taxa was identified 

 for 1959, with 82 taken to species, 33 to genus, 33 to family, 

 and 5 to order. Some of the developmental series recognized 

 originally could not be assigned scientific names, particularly 

 in the Bathylagidae, Myctophidae, and Pleuronectiformes. These 

 were given descriptive names, which later were changed to 

 scientific names as they became known. 



The task of producing a reliable and equitable 

 ichthyoplankton data base required extensive procedures to 

 verify, correct, and edit the original identifications. The 

 primary data source was the original identification sheets (see 

 Kramer et al., 1972, for examples); however, a critical resource 

 used in all phases of this process was the CalCOFI 

 ichthyoplankton collection in which the samples are archived. 

 Throughout the course of CalCOFI ichthyoplankton studies, samples 

 have been identified to the lowest taxon possible. In reviewing 

 these identifications for the data base, our approach has been 

 conservative and we have preserved those identifications and 

 counts which we could confirm, while correcting as many of the 

 errors as possible. During the coding of the identification 

 sheets, the "descriptive types" were assigned scientific names 

 and reexamined, if necessary. After computer entry, taxonomic 

 errors and inconsistencies in the data base were corrected and 

 the most obvious identification errors were corrected. Our 

 current knowledge of ichthyoplankton techniques coupled with a 

 precise understanding of the development of identification 

 competency in the program over the years allowed us to critically 

 judge the historical records. Identifications were changed to 

 different taxa, lumped to a higher taxonomic category, or given a 

 more precise taxonomic name. In many cases, identifications of a 

 taxon were inconsistent among cruises in a year, because of 

 varying competency of identifiers. These records were made 

 equitable by lumping to the higher taxonomic category to avoid 

 biases that could result in quantitative misinterpretations. 



Next, statistical, seasonal, and geographic outliers were 

 identified, employing a series of graphic summaries and listings. 

 Examination of geographic outliers proved to be especially 

 effective because of our accumulated knowledge of species 

 distributions. In the course of examining samples for these 

 outliers, other identification errors were discovered and 

 eventually all taxa were scrutinized to some extent. Lastly, 



