CCAMLR follows a precautionary approach in its management of the various resources for which it is responsible. 

It collects what data it can and then attempts to weigh up and balance the uncertainties associated with such data in a manner consistent with the Convention's objectives.

Management decisions are taken bearing such uncertainties in mind and in a manner which strives to minimise the risk of long-term adverse effects on the resources concerned rather than delaying decisions until all necessary data are available.

Further reading:

Hewitt, R.P. et al.  2002.  Setting a precautionary catch limit for Antarctic krill.  Oceanography, Vol. 15, No. 3