Report: http://www.ices.dk/reports/FTC/2005/SGUFM05.pdf

Fishing mortality (F) is defined by The Study Group on Unaccounted Mortality in Fisheries (ICES, 1995) as "'The sum of all fishing induced mortalities occurring directly as a result of catch or indirectly as a result of contact with or avoidance of the fishing gear'"

They give the equation:
F = Fc + Fb + Fd + Fe + Fo + Fg + Fa + Fh, where
Fc == landed catch
Fb == illegal, misreported, unreported
Fd == discard mortality: mortality from discards
Fe == escape mortality: mortality of fish that escape capture but still die
Fo == drop out mortality: fish that are caught in the net but are killed and fall out of the net before being brought aboard
Fa == avoidance mortality: death rate associated with the stress that fishing causes fish (i.e. avoiding the net)
Fg == ghost fishing mortality: fish that die in "ghost gear"--gear that is lost at sea
Fh == habitat degradation mortality

The most important of these are:
Fb, Fd, Fe, and Fg

Note: UFM == unaccounted fishing mortality

Illegal, Unreported, and Unregulated fishing (IUU):

On the international scene:

ICES working group concluded that science can contribute to the reduction of IUU by:

Note: IUU is possibly driven by (they recommend Bray 2000 and Schmidt 2004 for more info):

Estimating IUU

Discards

Escape Mortality

Ghost Fishing

The group working on quotas should read starting on PDF page 18.