Effective fish farm management requires accurate information on fish b
iomass in order to control feeding regimes, stocking densities and ult
imately the optimum time to harvest the stock. Current methods for bio
mass estimation are deemed inaccurate and may also be stressful to the
fish, Therefore, the ability to remotely predict fish weight and biom
ass was tested using a non-invasive, digital stereo-camera system. The
camera system was arranged in a vertical set-up, which grabbed images
of fish viewed from the side. Specific combinations of fin-fin, body
depth and length dimensions, visible from side views of fish, were mea
sured from stereo-images and these estimates were incorporated into a
series of multifactor regression equations that were used to predict w
eight. Biomass of Atlantic salmon (Salmo salar L.) was estimated to wi
thin 0.4% of the real value and individual weight was determined with
an error of -0.1 +/- 9.0%. Thus, the results from this study suggest t
hat biomass can be predicted with a high degree of accuracy using a st
ereo-camera system, and the method has the advantage of greatly reduce
d stress levels in fish, compared with current biomass estimation tech
niques.