How to use the fishery catch and catch per unit effort calculator
Estimate a fishery catch from catchability, fishing effort and fish stock size. Enter catchability coefficient, fishing effort, fish stock size in the fields above; the catch, catch per unit effort are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “fishery catch”, “catch per unit effort”, “catch equation q E N”, “calculate fishery catch and catch per unit effort”, “find catch”.
Formula
Variables
- q — Catchability coefficient
- E — Fishing effort (boat-days)
- N — Fish stock size (tonnes)
Worked example
With catchability coefficient = 0.001, fishing effort = 50 boat-days, fish stock size = 4000 tonnes, the calculator gives catch ≈ 200 tonnes; catch per unit effort ≈ 4 tonnes per boat-day.
Frequently asked questions
What is the fishery catch and catch per unit effort calculator used for?
Estimate a fishery catch from catchability, fishing effort and fish stock size. It helps with questions such as “fishery catch”, “catch per unit effort”, “catch equation q E N”.
What is the formula for the fishery catch and catch per unit effort calculation?
Catch (tonnes) = q × E × N. Catch per unit effort (tonnes per boat-day) = q × N. Here q is catchability coefficient, E is fishing effort (boat-days), N is fish stock size (tonnes).
What inputs do I need for the fishery catch and catch per unit effort calculator?
You need catchability coefficient, fishing effort in boat-days, fish stock size in tonnes. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the fishery catch and catch per unit effort calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the fishery catch and catch per unit effort result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.