OBIS is comparable to a scientific journal that makes data freely available on the internet. Thus the geographic and taxonomic scope, and quantity of data provided, depend on the scientists and organizations that provide data. However, in contrast to data in a journal, the ‘reader’ can select and combine data in OBIS from a variety of sources. OBIS and its users give feedback on data quality and possible errors to data providers. Because data providers are willing to correct errors, the quality of the data will increase in time. How OBIS provides quality assurance, who is primarily responsible for data published in OBIS (its owners), issues to be considered in using the data, and known gaps in the data, are described below.
Only data from authoritative scientists and science organizations approved by OBIS are served. All data are subject to quality control procedures before publication, and at regular intervals, with data providers informed of any discrepancies and potential errors (e.g. species names spelt incorrectly, mapping errors). OBIS also benefits from user peer-review and feedback to identify technical, geographic, and taxonomic errors in data served. However, although errors will exist as they do in any publication, OBIS is confident that the data are the best available in electronic form. That said, the user needs sufficient knowledge to judge the appropriate use of the data, i.e. for what purpose it is fit.
Many of the data published through OBIS have voucher specimens in institutional collections and museums, images of observations, and the original identifier of the specimens is often credited or will be contactable from the data custodian.
Data providers retain ownership of the data provided. OBIS does not own or control or limit the use of any data or products accessible through its website. Accordingly, it does not take responsibility for the quality of such data or products, or the use that people may make of them.
Appropriate caution is necessary in the interpretation of results derived from OBIS. Users must recognize that the analysis and interpretation of data require background knowledge and expertise about marine biodiversity (including ecosystems and taxonomy). Users should be aware of possible errors, including in the use of species names, geo-referencing, data handling, and mapping. They should cross-check their results for possible errors, and qualify their interpretation of any results accordingly.
Users should be aware that OBIS is a gateway to a system of databases distributed around the world. More information on OBIS data is available from the data sources websites and contact persons. Users should email any questions concerning OBIS data or tools (e.g. maps) to the appropriate contact person and copy this request to OBIS at firstname.lastname@example.org, or through the Contact Form on the web site.
Major gaps in data and knowledge about the oceans are reflected in OBIS' data coverage. Note the following:
- Most of the planet is more than 1 km under water: this deep sea is the least surveyed part of our world.
- Coastal areas have been adequately sampled only for the distribution of most vertebrates (birds, mammals, reptiles, larger fish)
- The oceans have been better sampled in the northern than the southern hemisphere, as reflected in the distribution of data in OBIS.
- Most marine species have not yet been recognized or named. A major effort is required to describe marine species, especially invertebrates and deep-sea organisms.
- Of the marine species that have been described, some have been discovered to be several species, and others combined into single species. Thus, there are changes in the application of species names over time. A checklist of all current marine species names is not available but it is estimated that 230,000 have been described. Only about half of these names have been organized into global species checklists. OBIS includes distribution data on (a) many of these validated names and (b) additional names that remain to be organized into global species checklists. Thus, OBIS has some distribution data for about half of the known marine species.
- Some species distribution data are not available in any form, as they have not have been published nor made available for databases.
- Only some of the recently collected, and less of the older published, data have been entered into databases. Thus databases are incomplete.
- Of existing databases, many are not connected to OBIS.
You can help address these data gaps by (a) recognizing and encouraging scientists and organizations to make their data available online so they are accessible to OBIS, and (b) advocating for and carrying out field surveys and taxonomic studies designed to fill geographic and taxonomic gaps in knowledge.