FYKE NET SURVEYING
Basic Survey – data is collected to determine fish species composition, relative abundance, and size structure.
Comprehensive Survey – in addition to the data collected in the Basic Survey, scale samples are also collected to determine growth rates of fish, and a “mark-recapture” population estimate is performed to determine the abundance of individual species present. Data collected will provide information on the reproductive success of fish species present as well.
Fish are captured by using 3’ x 5’ fyke nets having 50’ leads and ½” bar mesh. Fyke nets will be set at specific locations throughout the lake or pond. The number of “net-nights” (unit of effort; one net set overnight) will vary depending on the type of survey and the size of the water body. Typically, Comprehensive Surveys will require more “net-nights.” Lengths and catch-per-effort (relative abundance) data will be recorded for each fish encountered. With a Comprehensive Survey, scale samples will be collected from select species using a stratified random sampling design to estimate growth rates. Each individual scale sample will be aged in a laboratory. A process called back-calculating will be done to determine the length of the sample fish at each previous age.
For Comprehensive Surveys, all of the applicable data analyses listed below will be calculated and graphed from the age data and any additional length and/or weight data collected. These results will be compiled into an easy to understand report that includes recommendations for sustaining or improving the fishery.
• length at age (growth rate)
• length frequency
• proportional stock density
• growth trends
• age composition (relative year class strength)
• catch curves
• mortality rate data
• length - weight relationship
• condition factor data
• population estimates
Fishery surveys typically take place in spring or fall of the year (an exact date can be scheduled). Data analysis and report preparation will be completed within six months of the survey. Survey costs vary depending on the extent of detail and the size of the water body. These surveys are more affordable than you may think, and provide valuable information about your fish community. Call today for pricing of a survey that is customized to your needs.