Ocean Data Formats and Codes

Note: Please refer to the ITIS link for the most recent taxonomic codes data. Older NODC codes from CD-ROM Version 8.0 or Version 7.0 can be accessed from Taxonomic Code CDs Version 7 and 8: Accession 50418 in the Ocean Archive System.

Up to 1996, while it was in active use, the NODC Taxonomic Code was the largest, most flexible, and widely used of the various coding schemes which adapted the Linnean system of biological nomenclature to modern methods of data storage and retrieval. It was based on a system of code numbers that reflected taxonomic relationships. Over the years, the problems and shortcomings created by this approach became more apparent. At the same time, relational database management systems were developed that enabled efficient searches and retrievals to be conducted without the need for taxonomic information to be built into the code. Therefore, in 1996, NODC released the final version (#8) of the NODC Taxonomic Code on CD-ROM. This CD-ROM, now out of date, provided the old NODC codes along with their new ITIS Taxonomic Serial Numbers to facilitate the transition to a new Integrated Taxonomic Information System (ITIS). From that point in time, the NODC code was frozen and ITIS assumed responsibility for assigning new TSN codes, and verifying accepted scientific names and synonyms. ITIS is supported by a partnership of U.S. and international organizations, including NOAA/NODC. ITIS contains nearly 300,000 entries for terrestrial, marine, and freshwater species from all biological kingdoms. While it focuses on North American species (driven by the priorities of the current ITIS partners), it also includes worldwide treatment of selected groups of fishes, birds, reptiles, molluscs, corals, and other groups. ITIS is continually seeking new partnerships, and expanding its coverage.

History of the NODC Taxonomic Code

In 1972 Richard Swartz, Marvin Wass, and Donald Boesch published A Taxonomic Code for the Biota of Chesapeake Bay at the Virginia Institute of Marine Science (VIMS Special Scientific Report No. 62). Their efforts were specifically oriented toward development of a universally acceptable coding system since, as they succinctly put it, they felt that "everyone [should] use the same code." The VIMS codes contained a maximum of 10 digits, with each two digits representing a different level of the systematic hierarchy. The last six digits contained (exclusively) discrete taxonomic levels (families, genera, and species) while the first four digits variously represented phyla, classes, subclasses, and orders.

During the years 1974 and 1975, Dr. George Mueller of the University of Alaska developed a taxonomic code that enabled him and his colleagues to manage biological data for the Alaskan Outer Continental Shelf Environmental Assessment Program (OCSEAP). These codes, known as the "Alaska Species Codes" were based directly on the VIMS numeric concept but used a completely different numerical sequence.

In response to a request by the National Oceanographic Data Center for a taxonomic code into which virtually any existing taxon could be placed, Dr. Mueller developed the hierarchical structure on which the present NODC Taxonomic Code is based. Personnel at the National Oceanographic Data Center, under the leadership of Dr. Elaine Collins and Mary Hollinger, began adding taxa to this basic framework, and in 1977, published the first edition of the NODC Taxonomic Code. In this edition, which contained approximately 16,000 records, two digits were added to the basic lO-digit format in order to allow inclusion of subspecies or varieties.

A second edition containing approximately 18,000 records was published in 1978, and a third edition containing approximately 25,000 records was published in 1981. The last hard copy edition was published in 1984 and contained approximately 45,000 entries. Subsequent releases have been available only in digital format. The previous release, version 7.0, contained approximately 206,000 records.

Version 8.0 of the NODC Taxonomic Code was designed to serve as a bridge to a new system based on a different concept of managing biological data. Up to 1996, the NODC Taxonomic Code was based on 12-digit "intelligent" code numbers. By "intelligent" code numbers we mean that information about taxonomy was built into the codes through the use of 2-digit couplets to represent one or more levels of the taxonomic hierarchy. For example, a species assigned a 10-digit code would belong to the genus represented by the first 8 digits of the code. The numerical hierarchy of the code numbers therefore reflected taxonomic hierarchy as well.

Version 8.0 of the NODC Taxonomic Code, the final version, contained these "intelligent" code numbers, but also introduced the non-intelligent Taxonomic Serial Numbers (TSNs) used in the Integrated Taxonomic Information System (ITIS). The contents of this CD-ROM showed the final state of the old code numbers, and they will not be deleted or modified, nor will new ones be assigned.

If you would like NODC to create a CD-R of the data, there is a charge for that service. The same files are freely available from the Ocean Archive System, Accession # 50418.

If you have questions or need assistance regarding the old NODC Taxonomic Code, please contact NODC. For question regarding ITIS, please see their website:

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