|Scientific Name:||Scomber scombrus|
|Species Authority:||Linnaeus, 1758|
Scomber glauciscus Pallas, 1814
Scomber punctatus Couch, 1849
Scomber scomber Linnaeus, 1766
Scomber scriptus Couch, 1863
Scomber vernalis Mitchill, 1815
Scomber vulgaris S. D. W., 1837
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor/s:||Collette, B., Boustany, A., Carpenter, K.E., Di Natale, A., Fox, W., Graves, J., Juan Jorda, M., Kada, O., Nelson, R. & Oxenford, H.|
|Reviewer/s:||Russell, B. & Polidoro, B.|
This is a common and locally abundant species with fluctuating fishery landings. Based on a generation length range of 11–20 years, there has been a global SSB decline of between 3 and 14% over the past 11–20 years across the western and eastern stock. No information is available for the Mediterranean. It is listed as Least Concern. It is important to note however, that the greatest declines in SSB for this species occurred in the 1970s, before the time period comprising three generation lengths. Given that fishing mortality for the eastern stock is just above Fpa, careful fisheries management is needed. In addition, monitoring is needed as climate change may be causing shifts in this species distribution. The implications of these shifts and impacts on fishing effort and accessibility to the stock are unknown.
|Range Description:||In the western Atlantic this species is present from Labrador to Cape Lookout, U.S. and in the eastern Atlantic from Iceland to Mauritania, including the southwestern Baltic Sea, the Mediterranean and Black seas.|
Native:Albania; Algeria; Belgium; Bulgaria; Canada; Croatia; Cyprus; Denmark; Egypt; Estonia; Finland; France; Georgia; Germany; Gibraltar; Greece; Iceland; Ireland; Israel; Italy; Latvia; Lebanon; Libya; Lithuania; Malta; Monaco; Morocco; Netherlands; Norway; Poland; Portugal; Romania; Russian Federation; Slovenia; Spain; Sweden; Syrian Arab Republic; Tunisia; Turkey; Ukraine; United Kingdom; United States (Georgia); Western Sahara
|FAO Marine Fishing Areas:||
Atlantic – eastern central; Atlantic – northeast; Atlantic – northwest; Mediterranean and Black Sea
|Range Map:||Click here to open the map viewer and explore range.|
There are two separate populations, eastern and western, with little or no interchange. Separate stock assessments are conducted for each (ICES and DFO+NOAA).
The east Atlantic Mackerel stock is currently considered to comprise three main unit stocks (southern, western and North Sea), with variable proportions of these three mixing in the northerly feeding grounds. The southern component spawns in Spanish and Portuguese waters, and the western component spawns in the Bay of Biscay and northwards around Ireland and west/northwest of the U.K. The eastern Mediterranean populations (Greece, Italy) are separated genetically from the western Mediterranean stock (Barcelona) which forms a panmictic unit with eastern Atlantic populations (Zardoya et al. 2004). The third component spawns in the North Sea and Sakgerrak. Although the North Sea spawners form to some extent a discrete unit from the other ones, commercial catches cannot be allocated to individual stocks, and therefore assessments are undertaken for the combined stock (ICES 2006).
For the Western Component, estimates of the spawning stock biomass (SSB), derived from egg surveys, indicate a decrease of 14% between 1998 and 2001 and a 6% decrease from 2001 to the 2004 survey. The results from 2007 indicate a 5 % increase from 2004 to 2007 (STECF 2009). For the North Sea Component, the 2002 and 2005 triennial egg surveys in the North Sea both indicate similar egg production, but in 2008 it has decreased by about 40% (STECF 2009). For the Southern Component, catches increased from about 20 000 t in the early 1990s to 44 000 t in 1998, and were close to 50 000 t in 2002. Estimates of SSB, derived from egg surveys, are highly variable, and give average estimates of around 16% of the combined North Eastern Atlantic mackerel stock (1995–2007) (STECF 2009). The main catches are taken in the North Sea (ca. 50%), the Norwegian Sea (10%), west of UK and Ireland (15–20%), south of Ireland and in the Channel (ca. 15%) and the rest in the southern area.
Based on the most recent ICES estimate of SSB in 2009, the eastern stock is classified as having full reproductive capacity. Fishing mortality in 2008 is estimated to be just above Fpa (precautionary fishing mortality). SSB has increased by 47% since 2002 and is currently estimated to be above Bpa (precautionary biomass). The 2002 year class is the highest on record. Subsequent year classes are estimated to be about average (STECF 2009). The SSB is expected to remain stable in 2011 for a catch in the range of 527,000–572,000 tons (STECF 2009).
The northwest Atlantic Mackerel stock has been evaluated jointly by NOAA in the US and DFO in Canada (TRAC 2010). There is a high degree of uncertainty in this assessment, and available data do not allow for estimation of biological reference points. The current recommendation is that catch not exceed the average total landings of 2006–2008 (80,000 mt) until more information is available (TRAC 2010).
Based on a generation length of between 3.5 and 6.5 years (Western and Eastern Stocks respectively), decline can be measured over a period of 11–20 years. The TRAC 2010 report shows a SSB decline in the Western Stock of approximately 53% over 20 years (1987–2008) and a 33% over 11 years (1997–2008). Based on the ICES 2009 assessment (ICES 2009), the eastern stock SSB has declined 10% over the past 20 years (1987–2008), with no decline over the past 11 years (1997–2008). Declines were calculated based on linear regression of SSB biomass over time. The most recent stock assessment (ICES 2009), the SSB in the eastern Atlantic was estimated to be 1,670,000 tonnes. The SSB for the western Atlantic stock is estimated at 144,000 mt tonnes (roughly ten times smaller) (TRAC 2010). Based on these proportions, there has been a total SSB decline of between 3 and 14% over the past 11–20 years across the global range of this species.
|Habitat and Ecology:||
This is a pelagic, oceanodromous species. It is abundant in cold and temperate shelf areas, and forms large schools near the surface. They overwinter in deeper waters but move closer to shore in spring when water temperatures range between 11° and 14°C. Mainly diurnal, it feeds on zooplankton and small fish. Eggs and larvae are pelagic.
Maximum size for this species is 66 cm, although fish greater than 50 cm are uncommon. This species matures at approximately age two (O'Brien et al. 1993), with 100% maturity at age seven in some populations of the eastern stock (Skagen 1989). For the Western stock longevity is estimated to be about 12 years (Gregoire 1993), and for the Eastern stock longevity is estimated to be 18 years (Villamor et al. 2001). Generation length is therefore conservatively estimated to be about 3.5 years in the Western stock and 6.5 years in the Eastern stock (Collette et al. 2011). Disparities in longevity between stocks may valid, or may be due to differences in methods of age determination, environmental factors, and/or response to fishing pressure over time.
Maximum Size is 66 cm fork length (FL). The all-tackle game fish record is of a 1.2 kg fish caught in the Kraakvaag Fjord, Norway in 1992 (IGFA 2011).
|Major Threat(s):||This is a species with high commercial importance. It is caught with trawls, purse seines, gill and trammel nets. It is an important recreational species, fished with hook and line. Climate change may affect the distribution of this species, with possible movement towards the north, making it available for exploitation by additional nations. It is unknown whether this represents an expansion of habitat or if contraction will occur in the southern part of its range.|
Several eastern Atlantic countries have minimum landing sizes for this species: EU (18 cm), Ukraine (15 cm), Turkey (20 cm), Bulgaria (22 cm), Romania (23 cm).
ICES advises that any agreed total allowable catch (TAC) should cover all areas where Northeast Atlantic Mackerel are fished. The agreed management plan (F between 0.2 and 0.22) would imply catches between 527 000 t and 572 000 t in 2010. The SSB is expected to remain stable in 2011 for a catch in this range. ICES further advises that the existing measures to protect the North Sea spawning component remain in place. These include: areas restricted to fishing, seasonal closures, and minimum landing size (30 cm in North Sea and 20 cm in Skagerrak). In June 2009, an agreement was concluded between contracting parties to the Coastal States on mackerel banning high grading, discarding, and slipping from pelagic fisheries targeting mackerel, horse mackerel, and herring beginning in January 2010 (STECF 2009).
For the western Atlantic stock, there are no management measures in place. However, the most recent stock assessment recommends that annual total catches do not exceed the average total landings (80,000 mt tonnes) over the last three years (TRAC 2010).
|Citation:||Collette, B., Boustany, A., Carpenter, K.E., Di Natale, A., Fox, W., Graves, J., Juan Jorda, M., Kada, O., Nelson, R. & Oxenford, H. 2011. Scomber scombrus. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <www.iucnredlist.org>. Downloaded on 19 April 2014.|