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
Illegal, Unreported, and Unregulated fishing (IUU):
- IUU is a major source of uncertainty in stock assessments (they cite Bray 2000; Evans 2000; Ices, 1994, 2000, and 2004)
- Most information available is anecdotal
- Most estimates are fishery-specific
- FAO estimates that LEGAL and IUU kills about 8 million TONNES per year
- Mostly Tuna and deep sea species
- "Constitutes a doubling of catch in the last 20 years" (they cite Schmidt 2004)
- CCAMLR estimates the amount of IUU toothfish taken between 1997 and 2000 to be about 90,000 tonnes (more than 2x the registered catch levels)
- NEAFC says that almost 20% of the 2001 trade in redfish was IUU (they cite NEAFC, 2002)
- ICCAT (the tuna people) estimates that 18% of the tuna catch is IUU
- For most ICES stocks, IUU is responsible for "the single largest potential source of UFM" for the stock
- AFWG reports that 90 to 115 kilotonnes (I don't know if that was a unit, but it is now) of north east artic cod is IUU since 2002
- WGBFAS estimates that true baltic cod catches are 35-45% bigger than reported
- NWWG used satellite imagery to find that Redfish catches may be 25% greater than reported
- Other stock assessment working groups know that IUU is a major confounding factor, but have no way to quantify it (I think that if ICES can't get the data, we are toast)
On the international scene:
- IUU was formally recognized as a fishing problem at an FAO conference in 1992
- Schmidt, 2004 has a "brief" overview on subsequent regulations
- International Plan of Action for IUU Fishing (aka IPOA-IUU) is key
- defines stuff:
- Illegal fishing: fishing that is not in accordance with local laws, or fishing by a boat that is not allowed in those waters. (I guess those are the same)
- Unreported: either unreported or misreported catch data
- Unregulated: fishing "conducted in stocks for which no state (or RFMO) has taken responsibility for their management and conservation; or by vessels without nationality (or flying the flag of a state not party to any relevant RFMO) and who therefore do not consider themselves bound by the relevant national laws (or RFMO regulations)."
- goal is to "'prevent, deter, and eliminate IUU fishing'"
- defines stuff:
ICES working group concluded that science can contribute to the reduction of IUU by:
- Identifying affected stocks and fisheries
- Formulating practical solutions
- Developing approaches to managing the uncertainties that IUU creates
Note: IUU is possibly driven by (they recommend Bray 2000 and Schmidt 2004 for more info):
- Ineffective Management
- Fleet Overcapacity
- Bad enforcement
- economic incentives from flag hopping supporting states
- economic pressures
- LACK OF STIGMA ASSOCIATED WITH IUU--"UNDERESTIMATION OF ENVIRONMENTAL AND SOCIAL IMPACTS"
- IUU can start a "self propagating cycle" (they cite Schmidt 2004)
- IUU by one fisherman induces other fishermen to go IUU
- More IUU --> more uncertainty in estimates --> stricter regulations --> more IUU
- Paton, 2005 says that IUU can become part of the culture of a fishing village