Fish Population Dynamic and Stock Assessment

6.4.2.1. Gulland Equation

The following equation is most commonly used for estimation of potential yields.

MSY = M $$\cdot$$ 05 $$\cdot$$ Bv. ………………………………. (1)

Bv is the Virgin standing stock (Estimated in a trawling or acoustic survey)

M = Natural mortality coefficient

For less exploited stocks, the following equation is used.

MSY = Zt $$\cdot$$ 0.5 Bt. …………………………………. (2)

Zt is the exponential rate of total mortality (F + M = Z) of the year t.

Bt = standing stock size in that year