LarvalBase is a new module in FishBase aiming to present relevant information about fish larvae. To date, FishBase holds little information on ichthyoplankton and lacks detailed data on fish larvae identification and rearing. The LarvalBase project will close this gap and will complete various datasets in FishBase relevant to fish larvae.

Specifically, LarvalBase wants to build a comprehensive information system on fish larvae in aquaculture. For instance, egg size and development time are important in captive breeding of fish because they can influence the design of hatchery equipment and the management and husbandry of the life stages of fish held in captivity. Where new species are considered, LarvalBase will be able to generate a profile of the most probable requirements for the rearing process. At some stage, we hope that it will be possible to estimate the potential of a species to be reared successfully at a specific site by using the combined information in FishBase and LarvalBase.

Aquaculture scientists and other professionals often find it difficult to get information on species that have potential to be reared under local conditions. This is a situation where a well-focused database can help. Thus, the major concern of LarvalBase is to provide fisheries and hatchery managers with fast and easy access to all information relevant to the identification and rearing of fish larvae for aquaculture and stock enhancement and for the conservation and re-establishment of fish biodiversity.

Although the number of farmed finfish (about 200) is relatively small, there is a huge amount of aquaculture data available in journals and reports. Making generalizations from these data has been hampered by the lack of standardization in aquaculture experiments. These constraints will be addressed by efforts to standardize data. LarvalBase strives to provide a ‘model form’ that can be followed by specialists dealing with larval rearing.

LarvalBase deals with the period after hatching in two tables (Larval Nursery System and Fry Nursery System). The main larval stage is defined as the period from hatching (including the yolk-sac stage) until metamorphosis; sometimes the latter coincides with the ‘weaning’ period (i.e., transition from live food to formulated feed). The subsequent period is defined as the fry stage consisting of fish that have passed metamorphosis and need feed different from the larval stage. In addition, fry usually need to be transferred to other holding facilities for on-growing. The following stage is known as alevins or fingerlings. Alevins have all features of adults. This stage is usually sold to on-growing farms and/or used for stocking ponds, lakes, or large tanks in order to produce market-size fish.