Clupea harengus has been assessed as Least Concern. This is one of the most commercially important species within the northern Atlantic Ocean. Since a severe population crash in the stock in the 1970s, limits were imposed on the harvest levels of this species in an attempt to rebuild the stock. Since then the biomass has shown in an increase. Current estimates suggest that only 10% of the stock is being exploited and there are no reports of over-fishing occuring. Continued monitoring Continued monitoring of the harvest levels and stock biomass is needed to ensure limits can be revised should there be changes to the levels of recruitment.

This species is distributed from northern Bay of Biscay to Iceland and southern Greenland, eastward to Spitsbergen and Novaya Zemlya, including the Baltic. It is also seen along southwestern Greenland and Labrador down to South Carolina.

A US stock assessment (age classes 2+) of Georges Bank, Nantucket Shoals and the Gulf of Maine, estimated there to be 1.4 million metric tonnes in 2001 (Overholtz et al. 2004). Biomass is now thought to have declined to 1 million metric tonnes in 2005.

This benthopelagic, oceanodromous species, forms large schools in coastal waters. It feeds predominantly upon copepods, migrating up the water column at night to feed in shallower surface waters. The species is divided into several subspecies, with separate spawning times; these include the winter spawning Norwegian and Icelandic herrings, the autumn spawning Icelandic and North sea herrings and the Baltic herrings. Individuals mature at ages ranging from three to nine years. The Atlantic Herring ranges in depth from the surface to 200 m.

Three very large year classes were produced in 1994, 1998 and 2002 (TRAC 2006).

In the mid 20th century, the Atlantic Herring was considered to be one of the most commercially valuable food fish species.

Stocks of this species showed a strong reduction in the 1970s from global landings of 4,095,394 t in 1966, to 887,533 t in 1979. This decline was attributed to overfishing. Approximately 10-20% of these landings are taken from Area 21 (Northwest Atlantic) while the rest is taken in Area 27 (Northeast Atlantic). The largest reported catches are from Norway and Iceland. In the last 10 years global catches have shown an increase: 1998 - 2,421,462 t, 1999 - 2,411,408 t, 2000 - 2,381,011 t, 2001 - 1,952,605 t, 2002 - 1,873,503 t, 2003 - 1,958,929 t, 2004 - 2,020,111 t, 2005 - 2,316,050 t, 2006 - 2,244,595 t. While stocks hit critically low levels in the 1970s and showed signs of commercial extinction, they have since recovered (Melvin and Stephenson 2007).

The Northwest Atlantic stock is treated as two separate stocks: Gulf of Maine stock and Georges Bank-Nantucket Shoals stock. The Georges Bank stock crashed in the 1970s due to overexploitation by foreign fishers, while the Gulf of Maine stock continued to support coastal fisheries. The Georges Bank stock is now said to have fully recovered due to recolonisation from Gulf of Maine and Nantucket Shoals. The Bay of Fundy stock declined from approximately 570,000 mt in 1997 to 460,000 mt in 2000 - 2001, however in 2002/ 2003 it showed an increase (Melvin et al. 2004; NOAA 2005). Despite this increase there are concerns about the stock due to fewer adults in the population.

Current rates of fishing mortality in the U.S. fisheries are calculated to be approximately 10% indicating that stocks are under-utilised, however there is concern that the inshore Gulf of Maine stock is being over-exploited (NOAA 2005).

An average fishing mortality (F) of 0.7 was calculated for the 1970s, this declined to 0.3 in the 1980s, 0.15 in 1991 and has since remained stable at 0.1 since 2002 (TRAC 2006).

Atlantic Herring is commercially commercially harveste throughout its range.

In response to over-exploitation of stocks in the 1970s, Total Allowable Commercial Catch (TACC) limits were imposed. The current allowable biological catch for 2007-2009 has been set at 194,000 mt (NOAA 2007).

The Biological Maximum Sustainable Yield (BMSY) for this species has been calculated at 629,000 mt, so even with the current estimates of the stock biomass, it is still above this limit. The stock is not reported to be in an overfished condition, and no over-fishing is thought to be occurring (Overholtz 2006).

Continued monitoring of the harvest levels and stock biomass is needed to ensure limits can be revised should there be changes to the levels of recruitment.