This worksheet is an offline version of the MPA Density Ratio calculator provided on this site. No-take marine protected areas (MPAs) and other well-enforced reference areas provide excellent baselines against which to compare fished stocks. Fish densities (measured in kg/ha) inside and outside the MPA can be estimated from the results of fishing or visual surveys. The MPA Density Ratio (fished/unfished fish density) can then be calculated to serve as an indicator of stock status.
