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POPULATION MONITORING PROCEDURES PURPOSE: The purpose. of monitoring the Virgin River woundfin population is to chart long term population numbers. At the present no one knows if the Virgin River woundfin population is larger or smaller than it was ten, twenty, or one hundred years ago. The Team recommends initiation of a long range monitoring program in order to provide for future management needs. PROCEDURE: Seven sampling stations along the Virgin River have already been established. The location of these stations are included in this Appendix. Each station is being sampled three times a year. The sampling periods are as follows: (1) in early summer preferably the first two weeks of June and certainly no later than the first of July. This sampling time is intended to provide data on the amount of recruitment into the population from the April and May spawning ,peak; (2) in early autumn, preferably during the last two weeks in September and certainly no later than the middle of October. This sampling time will yield data on the size of the woundfin population after the summer growing and recruitment seaso~~. Any possible autumn recruitment can also be determined; (3) in late winter, any time during the month of March. This sampling time will provide data on the size of the population available for spring spawning and estimate the mortality rate from autumn to late winter. The purpose of this population monitoring effort is essentially to record numbers of woundfin. However, lengths are also being recorded in an attempt to differentiate between juvenile and adult fish and provide initial data on growth rates. Maps have been drawn of each sampling site and three subsites have been selected at each site to provide a good representation of available habitat types. Samplers at each subsite, using 1/8 inch mesh seines of adequate width, make repeated seine hauls until the numbers of woundfin captured represent 10% or less of the number captured in the first seine haul. A11 fish captured in each seine haul are placed in a container and held until the last seine haul is made. They are then measured and returned to the river. All fish species captured are counted and recorded. At each sampling site and at each sampling period, notes are taken on the habitat condition. Other physical, chemical, and biological data are also recorded. The data from these samplings will be compiled after each trip and annually at the end of the autumn sampling. An annual report 55