Abundance and biological traits of fish sampled by electrofishing (except specific abundance indices) on the River Oir since 1988 (France).

Since 1988, an annual campaign is conducted to quantify by
electrofishing the abundance of fishes in the Oir basin. Originally,
the main target species were salmon and trout. Beginning in 2000, eels
were monitored in the same way as salmonids. The inventory of the
entire fish community has been carried out on a network of seven
sites. It is usually done in September and october. Two sites are also
monitored in May for all species The data consist of 1738
electrofishing operations and 138765 fish caught. Biological traits
measured on the fish sampled are sex, maturity status, length, weight
and age. Some of the salmon, trout and eels are identified
individually with a pit tag. Scale sampling is carried out on a sample
to estimate the age of the fish. The survey is carried out under the
Research Observatory on Diadromous Fish in Coastal Streams (ERO
DiaPFC) program. The data are stored in the database of the ERO. They
are used to develop predictive models and tools for providing
scientific advice to improve the management of this heritage species.