Gloucester /ˈɡlɒstər/ is a city on Cape Ann in Essex County, Massachusetts, in the United States. It is part of Massachusetts' North Shore. The population was 28,789 at the 2010 U.S. Census.[2] An important center of the fishing industry and a popular summer destination, Gloucester consists of an urban core on the north side of the harbor and the outlying neighborhoods of Annisquam, Bay View, Lanesville, Folly Cove, Magnolia, Riverdale, East Gloucester, and West Gloucester.
History
See also: Timeline of Gloucester, Massachusetts
The boundaries of Gloucester originally included the town of Rockport, in an area dubbed "Sandy Bay". That village separated formally on February 27, 1840. In 1873, Gloucester was reincorporated as a city.
Early Gloucester
Gloucester was founded at Cape Ann by an expedition called the "Dorchester Company" of men from Dorchester (in the county of Dorset, England) chartered by James I in 1623. It was one of the first English settlements in what would become the Massachusetts Bay Colony, and predates both Salem in 1626 and Boston in 1630. The first company of pioneers made landing at Half Moon Beach and settled nearby, setting up fishing stages in a field in what is now Stage Fort Park. This settlement's existence is proclaimed today by a memorial tablet, affixed to a 50-foot (15 m) boulder in that park.
Life in this first settlement was harsh and it was short-lived. Around 1626 the place was abandoned, and the people removed themselves to Naumkeag (what is now called Salem, Massachusetts), where more fertile soil for planting was to be found. The meetinghouse was even disassembled and relocated to the new place of settlement. At some point in the following years – though no record exists – the area was slowly resettled. The town was formally incorporated in 1642. It is at this time that the name "Gloucester" first appears on tax rolls, although in various spellings. The town took its name from the city of Gloucester in South-West England, perhaps from where many of its new occupants originated but more likely because Gloucester, England, was a Parliamentarian stronghold, successfully defended with the aid of the Earl of Essex against the King in the Siege of Gloucester of 1643.
This new permanent settlement focused on the Town Green area, an inlet in the marshes at a bend in the Annisquam River. This area is now the site of Grant Circle, a large traffic rotary at which Massachusetts Route 128 mingles with a major city street (Washington Street/Rt 127). Here the first permanent settlers built a meeting house and therefore focused the nexus of their settlement on the "Island" for nearly 100 years. Unlike other early coastal towns in New England, development in Gloucester was not focused around the harbor as it is today, rather it was inland that people settled first. This is evidenced by the placement of the Town Green nearly two miles from the harbor-front.
The Town Green is also where the settlers built the first school. By Massachusetts Bay Colony Law, any town boasting 100 families or more had to provide a public schoolhouse. This requirement was met in 1698, with Thomas Riggs standing as the town's first schoolmaster.
The White-Ellery House was erected in 1710 upon the Town Green. It was built at the edge of a marsh for Gloucester’s first settled minister, the Reverend John White (1677–1760).[3]
Early industry included subsistence farming and logging. Because of the poor soil and rocky hills, Cape Ann was not well suited for farming on a large scale. Small family farms and livestock provided the bulk of the sustenance to the population. Fishing, for which the town is known today, was limited to close-to-shore, with families subsisting on small catches as opposed to the great bounties yielded in later years. The fisherman of Gloucester did not command the Grand Banks until the mid-18th century. Historian Christine Heyrman, examining the town's society between 1690 and 1750, finds that at the beginning community sensibility was weak in a town that was a loose agglomeration of individuals. Commerce and capitalism transformed the society, making it much more closely knit with extended families interlocking in business relationships.[4]
Early Gloucestermen cleared great swaths of the forest of Cape Ann for farm and pasture land, using the timber to build structures as far away as Boston. The rocky moors of Gloucester remained clear for two centuries until the forest reclaimed the land in the 20th century. The inland part of the island became known as the "Commons", the "Common Village", or "Dogtown". Here small dwellings lay scattered amongst the boulders and swamps, along roads that meandered through the hills. These dwellings were at times little more than shanties; only one was even two stories tall. Despite their size, several generations of families were raised in such houses. One feature of the construction of these houses was that under one side of the floor was dug a cellar hole (for the keeping of food), supported by a foundation of laid-stone (without mortar). These cellar holes are still visible today along the trails throughout the inland part of Gloucester; they, and some walls, are all that remain of the village there.
Gloucester Harbor, ca. 1877, William Morris Hunt
Growth
1893 map of Gloucester
The town grew, and eventually colonists lived on the opposite side of the Annisquam River. This, in a time of legally mandated church attendance, was a long way to walk – or row – on a Sunday morning. In 1718 the settlers on the opposite shore of the river split off from the First Parish community at the Green and formed "Second Parish". While still part of the town of Gloucester, the people of Second, or "West", Parish now constructed their own meetinghouse and designated their own place of burial, both of which were in the hills near the marshes behind Wingaersheek Beach. The meetinghouse is gone now, but deep in the woods on the Second Parish Road, Old Thompson road, one can still find the stone foundation and memorial altar, as well as scattered stones of the abandoned burial ground.
Other parts of town later followed suit. Third Parish, in northern Gloucester, was founded in 1728. Fourth Parish split off from First Parish in 1742. Finally, in 1754, the people of Sandy Bay (what would later be called Rockport) split off from First Parish to found Fifth Parish. The Sandy Bay church founding was the last religious re-ordering of the colonial period. All of these congregations still exist in some form, with the exception of Fourth Parish, the site of whose meeting house is now a highway.
At one time, there was a thriving granite industry in Gloucester.
Geography and transportation
Good Harbor Beach, a beach in Gloucester
Gloucester is located at 42°37′26″N 70°40′32″W (42.624015, −70.675521).[5] According to the United States Census Bureau, the city has a total area of 41.5 square miles (107.5 km2), of which 26.2 square miles (67.8 km2) is land and 15.3 square miles (39.6 km2), or 36.88%, is water.[6]
Gloucester occupies most of the eastern end of Cape Ann, except for the far tip, which is the town of Rockport. The city is split in half by the Annisquam River, which flows northward through the middle of the city into Ipswich Bay. At its south end it is connected to Gloucester Harbor by the Blynman Canal. The land along the northwestern shore of the river is marshy, creating several small islands. Gloucester Harbor is divided into several smaller coves, including the Western Harbor (site of the Fisherman's Memorial) and the Inner Harbor (home to the Gloucester fishing fleet). The eastern side of Gloucester Harbor is divided from the rest of Massachusetts Bay by Eastern Point, extending some 2 miles (3 km) outward from the mainland. There are several parks in the city, the largest of which are Ravenswood Park, Stage Fort Park and Mount Ann Park.
Gloucester lies between Ipswich Bay to the north and Massachusetts Bay to the south. The city is bordered on the east by Rockport, and on the west by Ipswich, Essex and Manchester-by-the-Sea to the west. (The town line with Ipswich is located across Essex Harbor, and as such there is no land connection between the towns.) Gloucester lies 16 miles (26 km) east-northeast of Salem and 31 miles (50 km) northeast of Boston. Gloucester lies at the eastern terminus of Route 128, which ends at Route 127A. Route 127A begins at Route 127 just east of the Route 128 terminus, heading into Rockport before terminating there. Route 127 enters from Manchester-by-the-Sea before crossing the Blynman Canal and passing through downtown towards Rockport. It then re-enters Gloucester near Folly Cove, running opposite of its usual north-south orientation towards its terminus at Route 128. Route 133 also terminates within the city, entering from Essex and terminating just west of the Blynman Canal at Route 127. Besides the bridge over the Blynman Canal, there are only two other connections between the eastern and western halves of town, the A. Piatt Andrew Memorial Bridge, carrying Route 128, and the Boston & Maine Railroad Bridge, just north of the Blynman Canal.
Gloucester is home to the Cape Ann Transportation Authority, which serves the city and surrounding towns. Two stops, in West Gloucester and in downtown Gloucester, provide access to the Newburyport/Rockport Line of the MBTA Commuter Rail, which extends from Rockport along the North Shore to Boston's North Station. The nearest airport is the Beverly Municipal Airport, with the nearest national and international air service being at Boston's Logan International Airport.
Nearby towns :
Cities
Amesbury
Beverly
Gloucester
Haverhill
Lawrence (traditional county seat)
Lynn
Methuen
Newburyport
Peabody
Salem (traditional county seat)
Towns
Andover
Boxford
Danvers (Salem Village)
Essex
Georgetown
Groveland
Hamilton
Ipswich
Lynnfield
Manchester-by-the-Sea
Marblehead
Merrimac
Middleton
Nahant
Newbury
North Andover
Rockport
Rowley
Salisbury
Saugus
Swampscott
Topsfield
Wenham
West Newbury
Census-designated places
Andover
Boxford
Essex
Ipswich
Rockport
Rowley
Salisbury
Topsfield
Other villages
Annisquam
Ballardvale
Beverly Farms
Bradford
Byfield
Clifton
Magnolia
Merrimacport
Plum Island
Mackerel is a common name applied to a number of different species of pelagic fish, mostly, but not exclusively, from the family Scombridae. They are found in both temperate and tropical seas, mostly living along the coast or offshore in the oceanic environment.
Mackerel typically have vertical stripes on their backs and deeply forked tails. Many species are restricted in their distribution ranges, and live in separate populations or fish stocks based on geography. Some stocks migrate in large schools along the coast to suitable spawning grounds, where they spawn in fairly shallow waters. After spawning they return the way they came, in smaller schools, to suitable feeding grounds often near an area of upwelling. From there they may move offshore into deeper waters and spend the winter in relative inactivity. Other stocks migrate across oceans.
Smaller mackerel are forage fish for larger predators, including larger mackerel and Atlantic cod.[2] Flocks of seabirds, as well as whales, dolphins, sharks and schools of larger fish such as tuna and marlin follow mackerel schools and attack them in sophisticated and cooperative ways. Mackerel is high in omega-3 oils and is intensively harvested by humans. In 2009, over five million tons were landed by commercial fishermen[1] (see graph on the right). Sport fishermen value the fighting abilities of the king mackerel.[3]
Species
Over 30 different species, principally belonging to the family Scombridae, are commonly referred to as mackerel. The term "mackerel" means "marked" or "spotted", and derives from the Old French maquerel, around 1300, meaning a pimp or procurer. The connection is not altogether clear, but mackerel spawn enthusiastically in shoals near the coast, and medieval ideas on animal procreation were creative.[4]
Scombroid mackerels
About 21 species in the family Scombridae are commonly called mackerel. The type species for the scombroid mackerel is the Atlantic mackerel, Scomber scombrus. Until recently, Atlantic chub mackerel and Indo-Pacific chub mackerel were thought to be subspecies of the same species. In 1999, Collette established, on molecular and morphological considerations, that these are separate species.[5] Mackerel are smaller with shorter lifecycles than their close relatives, the tuna, which are also members of the same family.[6][7]
This article is part of a series on
Commercial fish
Blue walleye.jpg
Large pelagic
billfish bonito mackerel salmon shark tuna
Forage
anchovy herring menhaden sardine shad sprat
Demersal
cod eel flatfish pollock ray
Mixed
carp tilapia
vte
Scombrini, the true mackerels
The true mackerels belong to the tribe Scombrini.[8] The tribe consists of seven species, each belonging to one of two genera: Scomber and Rastrelliger.[9][10]
True Mackerels (tribe Scombrini)
Common name Scientific name Maximum
length Common
length Maximum
weight Maximum
age Trophic
level FishBase FAO IUCN status
Short mackerel Rastrelliger brachysoma
(Bleeker, 1851) 34.5 cm 20 cm kg years 2.72 [11] [12] DD IUCN 3 1.svg Data deficient[13]
Island mackerel R. faughni
(Matsui, 1967) 20 cm cm 0.75 kg years 3.4 [14] DD IUCN 3 1.svg Data deficient[15]
Indian mackerel R. kanagurta
(Cuvier, 1816) 35 cm 25 cm kg 4 years 3.19 [16] [17] DD IUCN 3 1.svg Data deficient[18]
Blue mackerel Scomber australasicus
(Cuvier, 1832) 44 cm 30 cm 1.36 kg years 4.2 [19] LC IUCN 3 1.svg Least concern[20]
Atlantic chub mackerel S. colias
(Gmelin, 1789) cm cm kg years 3.91 [21] LC IUCN 3 1.svg Least concern[22]
Chub mackerel S. japonicus
(Houttuyn, 1782) 64 cm 30 cm 2.9 kg 18 years 3.09 [23] [24] LC IUCN 3 1.svg Least concern[25]
Atlantic mackerel S. scombrus
(Linnaeus, 1758) 66 cm cm kg 12 years west
18 years east 3.65 [26] [27] LC IUCN 3 1.svg Least concern[5]
Scomberomorini, the Spanish mackerels
The Spanish mackerels belong to the tribe Scomberomorini, which is the "sister tribe" of the true mackerels.[28] This tribe consists of 21 species in all—18 of those are classified into the genus Scomberomorus,[29] two into Grammatorcynus,[30] and a single species into the monotypic genus Acanthocybium.[31]
Spanish Mackerels (tribe Scomberomorini)
Common name Scientific name Maximum
length Common
length Maximum
weight Maximum
age Trophic
level FishBase FAO IUCN status
Wahoo Acanthocybium solandri
(Cuvier in Cuvier and Valenciennes, 1832) 250 cm 170 cm 83 kg years 4.4 [32] LC IUCN 3 1.svg Least concern[33]
Shark mackerel Grammatorcynus bicarinatus
(Quoy & Gaimard, 1825) 112 cm cm 13.5 kg years 4.5 [34] LC IUCN 3 1.svg Least concern[35]
Double-lined mackerel G. bilineatus
(Rüppell, 1836) 100 cm 50 cm 3.5 kg years 4.18 [36] LC IUCN 3 1.svg Least concern[37]
Serra Spanish mackerel Scomberomorus brasiliensis
(Collette, Russo & Zavala-Camin, 1978) cm cm kg years 3.31 [38] LC IUCN 3 1.svg Least concern[39]
King mackerel S. cavalla
(Cuvier, 1829) 184 cm 70 cm 45 kg 14 years 4.5 [40] [41] LC IUCN 3 1.svg Least concern[42]
Narrow-barred Spanish mackerel S. commerson
(Lacepède, 1800) 240 cm 120 cm kg years 4.5 [43] [44] NT IUCN 3 1.svg Near threatened[45]
Monterey Spanish mackerel S. concolor
(Lockington, 1879) cm cm kg years 4.24 [46] VU IUCN 3 1.svg Vulnerable[47]
Indo-Pacific king mackerel S. guttatus
(Bloch & Schneider, 1801) 76 cm 55 cm kg years 4.28 [48] [49] DD IUCN 3 1.svg Data deficient[50]
Korean mackerel S. koreanus
(Kishinouye, 1915) 150 cm 60 cm 15 kg years 4.2 [51] LC IUCN 3 1.svg Least concern[52]
Streaked Spanish mackerel S. lineolatus
(Cuvier, 1829) 80 cm 70 cm kg years 4.5 [53] LC IUCN 3 1.svg Least concern[54]
Atlantic Spanish mackerel S. maculatus
(Mitchill, 1815) 91 cm cm 5.89 kg 5 years 4.5 [55] [56] LC IUCN 3 1.svg Least concern[57]
Papuan Spanish mackerel S. multiradiatus
Munro, 1964 35 cm cm 0.5 kg years 4.0 [58] LC IUCN 3 1.svg Least concern[59]
Australian spotted mackerel S. munroi
(Collette & Russo, 1980) 104 cm cm 10.2 kg years 4.3 [60] NT IUCN 3 1.svg Near threatened[61]
Japanese Spanish mackerel S. niphonius
(Cuvier, 1832) 100 cm cm 7.1 kg years 4.5 [62] [63] DD IUCN 3 1.svg Data deficient[64]
Queen mackerel S. plurilineatus
Fourmanoir, 1966 120 cm cm 12.5 kg years 4.2 [65] DD IUCN 3 1.svg Data deficient[66]
Queensland school mackerel S. queenslandicus
(Munro, 1943) 100 cm 80 cm 12.2 kg years 4.5 [67] LC IUCN 3 1.svg Least concern[68]
Cero mackerel S. regalis
(Bloch, 1793) 183 cm cm 7.8 kg years 4.5 [69] LC IUCN 3 1.svg Least concern[70]
Broadbarred king mackerel S. semifasciatus
(Macleay, 1883) 120 cm cm kg 10 years 4.5 [71] LC IUCN 3 1.svg Least concern[72]
Pacific sierra S. sierra
(Cuvier, 1832) 99 cm 60 cm 8.2 kg years 4.5 [73] LC IUCN 3 1.svg Least concern[74]
Chinese mackerel S. sinensis
(Cuvier, 1832) 247 cm 100 cm kg years 4.5 [75] DD IUCN 3 1.svg Data deficient[76]
West African Spanish mackerel S. tritor
(Cuvier, 1832) cm cm kg years 4.26 [77] LC IUCN 3 1.svg Least concern[78]
Other mackerel
In addition, a number of species with mackerel-like characteristics in the families Carangidae, Hexagrammidae and Gempylidae are commonly referred to as mackerel. There has been some confusion between the Pacific jack mackerel (Trachurus symmetricus) and the heavily harvested Chilean jack mackerel (Trachurus murphyi). These have been thought at times to be the same species, but are now recognised as separate species.[79]
Other mackerel species
Family Common name Scientific name Maximum
length Common
length Maximum
weight Maximum
age Trophic
level FishBase FAO IUCN status
Scombridae
Gasterochisma Butterfly mackerel Gasterochisma melampus Richardson, 1845 175 cm 153 cm kg years 4.4 [80] LC IUCN 3 1.svg Least concern[81]
Carangidae
Jack mackerel Atlantic horse mackerel Trachurus trachurus (Linnaeus, 1758) 70 cm 22 cm 2.0 kg years 3.64 [82] [83] Not assessed
Blue jack mackerel T. picturatus (Bowdich, 1825) 60 cm 25 cm kg years 3.32 [84] DD IUCN 3 1.svg Data deficient[85]
Cape horse mackerel T. capensis (Castelnau, 1861) 60 cm 30 cm kg years 3.47 [86] [87] Not assessed[88]
Chilean jack mackerel T. murphyi (Nichols, 1920) 70 cm 45 cm kg 16 years 3.49 [89] [90] DD IUCN 3 1.svg Data deficient[91]
Cunene horse mackerel T. trecae (Cadenat, 1950) 35 cm cm 2.0 kg years 3.49 [92] [93] Not assessed
Greenback horse mackerel T. declivis (Jenyns, 1841) 64 cm 42 cm kg 25 years 3.93 [94] [95] Not assessed[96]
Japanese horse mackerel T. japonicus (Temminck & Schlegel, 1844) 50 cm 35 cm 0.66 kg 12 years 3.4 [97] [98] Not assessed
Mediterranean horse mackerel T. mediterraneus (Steindachner, 1868) 60 cm 30 cm kg years 3.59 [99] [100] Not assessed
Pacific jack mackerel T. symmetricus (Ayres, 1855) 81 cm 55 cm kg 30 years 3.56 [101] LC IUCN 3 1.svg Least concern[102]
Yellowtail horse mackerel T. novaezelandiae (Richardson, 1843) 50 cm 35 cm kg 25 years 4.5 [103] Not assessed
Gempylidae
Snake mackerel Black snake mackerel Nealotus tripes (Johnson, 1865) 25 cm 15 cm kg years 4.2 [104] Not assessed
Blacksail snake mackerel Thyrsitoides marleyi (Fowler, 1929) 200 cm 100 cm kg years 4.19 [105] Not assessed
Snake mackerel Gempylus serpens (Cuvier, 1829) 100 cm 60 cm kg years 4.35 [106] Not assessed
Violet snake mackerel Nesiarchus nasutus (Johnson, 1862) 130 cm 80 cm kg years 4.33 [107] Not assessed
* White snake mackerel Thyrsitops lepidopoides (Cuvier, 1832) 40 cm 25 cm kg years 3.86 [108] Not assessed
Hexagrammidae Okhotsk atka mackerel Pleurogrammus azonus (Jordan & Metz, 1913) 62 cm cm 1.6 kg 12 years 3.58 [109] [110] Not assessed
Atka mackerel P. monopterygius (Pallas, 1810) 56.5 cm cm 2.0 kg 14 years 3.33 [111] Not assessed
Still life with mackerel, lemon and tomato, Van Gogh, 1886
The term mackerel is also used as a modifier in the common names of other fish, sometimes indicating the fish has vertical stripes similar to a scombroid mackerel:
Mackerel icefish—Champsocephalus gunnari
Mackerel pike—Cololabis saira
Mackerel scad—Decapterus macarellus
Mackerel shark—several species
Sharp-nose mackerel shark—Isurus oxyrinchus
Mackerel tuna—Euthynnus affinis
Mackerel tail goldfish—Carassius auratus
By extension, the term is applied also to other species such as the mackerel tabby cat,[112] and to inanimate objects such as the altocumulus mackerel sky cloud formation.[113]
Characteristics
Like other scombroids, mackerel such as this Atlantic mackerel are superb swimmers, and can retract their fins into grooves on their bodies for streamlining. They have deeply forked tails and are smaller and slimmer than tuna.[114][115]
Most mackerel belong to the family Scombridae, which also includes tuna and bonito. Generally mackerel are much smaller and slimmer than tuna, though in other respects they share many common characteristics. Their scales, if present at all, are extremely small. Like tuna and bonito, mackerel are voracious feeders, and are swift and manoeuvrable swimmers, able to streamline themselves by retracting their fins into grooves on their body. Like other scombroids, their bodies are cylindrical with numerous finlets on the dorsal and ventral sides behind the dorsal and anal fins, but unlike the deep-bodied tuna, they are slim.[114]
The type species for scombroid mackerels is the Atlantic mackerel, Scomber scombrus. These fish are iridescent blue-green above with a silvery underbelly and twenty to thirty near vertical wavy black stripes running across their upper body.[26][116]
It might seem that the prominent stripes on the back of mackerels are there to provide camouflage against broken backgrounds. That is not the case, because mackerel live in midwater pelagic environments which have no background.[117] However, fish have an optokinetic reflex in their visual systems which can be sensitive to moving stripes.[118] In order for fish to school efficiently, they need feedback mechanisms that help them align themselves with adjacent fish, and match their speed. The stripes on neighbouring fish provide "schooling marks" which signal changes in relative position.[117][119]
Mackerel, such as these Pacific jack mackerel, usually have vertical stripes on their sides which provide "schooling marks", visual clues that help them stay in formation as they school.[117]
There is a layer of thin reflecting platelets on some of the mackerel stripes. In 1998, E J Denton and D M Rowe argued that these platelets transmit additional information to other fish about how a given fish moves. As the orientation of the fish changes relative to another fish, the amount of light reflected to the second fish by this layer also changes. This sensitivity to orientation gives the mackerel "considerable advantages in being able to react quickly while schooling and feeding."[120]
Mackerel range in size from small forage fish to larger game fish. Coastal mackerel tend to be small.[121] The king mackerel is an example of a larger mackerel. Most fish are cold-blooded, but there are exceptions. Certain species of fish maintain elevated body temperatures. Endothermic bony fishes are all in the suborder Scombroidei and include the butterfly mackerel, a species of primitive mackerel.[122]
Mackerel are strong swimmers. Atlantic mackerel can swim at a sustained speed of 0.98 metres/sec with a burst speed of 5.5 m/s,[123][124] while chub mackerel can swim at a sustained speed of 0.92 m/s with a burst speed of 2.25 m/s.[114]
Distribution
King mackerels cruise on long migrations at 10 kilometres per hour.[125][126]
Most mackerel species have restricted distribution ranges.[114]
Atlantic Spanish mackerel (Scomberomorus maculatus) occupy the waters off the east coast of North America from the Cape Cod area south to the Yucatan Peninsula. Its population is considered to include two fish stocks, defined by geography. As summer approaches, one stock moves in large schools north from Florida up the coast to spawn in shallow waters off the New England coast. It then returns to winter in deeper waters off Florida. The other stock migrates in large schools along the coast from Mexico to spawn in shallow waters of the Gulf of Mexico off Texas. It then returns to winter in deeper waters off the Mexican coast.[56] These stocks are managed separately, even though genetically they are identical.[57]
The Atlantic mackerel (Scomber scombrus) is a coastal species found only in the north Atlantic. The stock on the west side of the Atlantic is largely independent of the stock on the east side. The stock on the east Atlantic currently operates as three separate stocks, the southern, western and North Sea stocks, each with their own migration patterns. Some mixing of the east Atlantic stocks takes place in feeding grounds towards the north, but there is almost no mixing between the east and west Atlantic stocks.[5][127][128][129][130]
Another common coastal species, the chub mackerel (Scomber japonicus), is absent from the Atlantic Ocean but is widespread across both hemispheres in the Pacific, where its migration patterns are somewhat similar to those of Atlantic mackerel. In the northern hemisphere, chub mackerel migrate northwards in the summer to feeding grounds, and southwards in the winter when they spawn in relatively shallow waters. In the southern hemisphere the migrations are reversed. After spawning, some stocks migrate down the continental slope to deeper water and spend the rest of the winter in relative inactivity.[23]
The Chilean jack mackerel (Trachurus murphyi), the most intensively harvested mackerel-like species, is found in the south Pacific from West Australia to the coasts of Chile and Peru.[89] A sister species, the Pacific jack mackerel (Trachurus symmetricus), is found in the north Pacific. The Chilean jack mackerel occurs along the coasts in upwelling areas, but also migrates across the open ocean. Its abundance can fluctuate markedly as ocean conditions change,[91] and is particularly affected by the El Niño.
Three species of jack mackerels are found in coastal waters around New Zealand: the Australasian, Chilean and Pacific jack mackerels. They are mainly captured using purse seine nets, and are managed as a single stock that includes multiple species.[131]
Some mackerel species migrate vertically. Adult snake mackerels conduct a diel vertical migration, staying in deeper water during the day and rising to the surface at night to feed. The young and juveniles also migrate vertically but in the opposite direction, staying near the surface during the day and moving deeper at night.[132] This species feeds on squid, pelagic crustaceans, lanternfishes, flying fishes, sauries and other mackerel.[133] It is in turn preyed upon by tuna and marlin.[134]
Life cycle
Gannets and other seabirds fuel themselves with mackerel
Mackerel are prolific broadcast spawners and must breed near the surface of the water due to the eggs of the females floating. Individual females lay between 300,000 and 1,500,000 eggs.[114] Their eggs and larvae are pelagic, that is, they float free in the open sea. The larvae and juvenile mackerel feed on zooplankton. As adults they have sharp teeth, and hunt small crustaceans such as copepods, as well as forage fish, shrimp and squid. In turn they are hunted by larger pelagic animals such as tuna, billfish, sea lions, sharks and pelicans.[24][41][135]
Off Madagascar, spinner sharks follow migrating schools of mackerel.[136] Bryde's whales feed on mackerel when they can find them. They use several feeding methods, including skimming the surface, lunging, and bubble nets.[137]
Fisheries
Global capture of mackerel in tonnes reported by the FAO 1950–2009
↑ Scombroid mackerels[1]
↑ Non-scombroid mackerels[1]
Main commercial species
The chub mackerel is the most intensively fished mackerel in the scombroid family
Chilean jack mackerel have been overfished and may be in danger of collapsing. Here an entire school of about 400 tons is encircled by a purse seiner.
Chub mackerel, Scomber japonicus, are the most intensively fished scombroid mackerel. As can be seen from the graph on the right, they account for about half the total capture production of scombroid mackerels.[1] As a species they are easily confused with Atlantic mackerel. Chub mackerel migrate long distances in oceans and across the Mediterranean. They can be caught with drift nets and suitable trawls, but are most usually caught with surround nets at night by attracting them with lampara lamps.[138]
The remaining catch of scombroid mackerels is divided equally between the Atlantic mackerel and all other scombroid mackerels. Just two species account for about 75% of the total catch of scombroid mackerels.[1]
Chilean jack mackerel are the most commonly fished non-scombroid mackerel, fished as heavily as chub mackerel[1][90] (see second graph on the right). The species has been overfished, and its fishery may now be in danger of collapsing.[139][140]
Smaller mackerel behave like herrings, and are captured in similar ways.[141] Fish species like these, which school near the surface, can be caught efficiently by purse seining. Huge purse seiner vessels use spotter planes to locate the schooling fish. Then they close in using sophisticated sonar to track the shape of the shoal. Entire schools are then encircled with fast auxiliary boats which deploy purse seine nets as they speed around the school.[142][143]
Suitably designed trollers can also catch mackerels effectively when they swim near the surface. Trollers typically have several long booms which they lift and drop with "topping lifts". They haul their lines with electric or hydraulic reels.[144] Fish aggregating devices are also used to target mackerel.[145]
Images and videos
Management
The North Sea has been overfished to the point where the ecological balance has become disrupted and many jobs in the fishing industry have been lost.[146]
The Southeast US region spans the Gulf of Mexico, the Caribbean Sea and the US Southeast Atlantic. Overfishing of king and Spanish mackerel occurred in the 1980s. Regulations were introduced to restrict the size, amount of catch, fishing locations and bag limits for recreational fishers as well as commercial fishers. Gillnets were banned in waters off Florida. By 2001, the mackerel stocks had bounced back.[147]
As food
Atlantic mackerel on ice at a fishmongers
Main article: Mackerel as food
Mackerel is an important food fish that is consumed worldwide.[148] As an oily fish, it is a rich source of omega-3 fatty acids.[149] The flesh of mackerel spoils quickly, especially in the tropics, and can cause scombroid food poisoning. Accordingly, it should be eaten on the day of capture, unless properly refrigerated or cured.[150]
Mackerel preservation is not simple. Before the 19th-century development of canning and the widespread availability of refrigeration, salting and smoking were the principal preservation methods available.[151] Historically in England, this fish was not preserved, but was consumed only in its fresh form. However, spoilage was common, leading the authors of The Cambridge Economic History of Europe to remark: "There are more references to stinking mackerel in English literature than to any other fish!"[141] In France mackerel was traditionally pickled with large amounts of salt, which allowed it to be sold widely across the country.[141]