Mackerel are streamlined predatory fish that inhabit cold waters and continental shelf areas and often migrate close to shore in the spring. They form large schools that feed on fish larvae and crustaceans. They often spawn in the spring. Individual females may lay hundreds of thousands of eggs in a season.
Mackerels are important food, commercial, and sport fishes. The flesh of king mackerel has occasionally been toxic to humans because, it is believed, it sometimes feeds on pufferfish. As of the the 1990s the Monterrey Spanish mackerel was listed as Endangered,
Top Mackerel Commercial Fish Species
Common name(s) — Scientific name — Harvest in tonnes (1000 kilograms)
1) Pacific mackerel (chub mackerel)— Scomber japonicus — 1,581,314 tonnes
2) Atlantic mackerel — Scomber scombrus — 910,697 tonnes
4) Chilean jack mackerel — Trachurus murphyi — 447,060 tonnes
5) Cape horse mackerel — Trachurus capensis — 356,795 tonnes
6) Indian mackerel — Rastrelliger kanagurta — 325,612 tonnes
7) Short mackerel — Rastrelliger brachysoma — 312,930 tonnes
8) Narrow-barred Spanish mackerel — Scomberomorus commerson — 256,469 tonnes
9) Atlantic horse mackerel — Trachurus trachurus — 205,807 tonnes
10 Japanese jack mackerel — Trachurus japonicus — 202,816 tonnes
[Source: Food and Agriculture Organization of the United Nations (FAO), 2012; Wikipedia]
Mackerel are an important middle-link in the food chain, providing food for sharks, dolphins, tuna and other large fish and are heavily fished by commercial fishermen. Mackerel often swim with their mouths wide open like “living colanders” to entrap tiny crustaceans in their expanded gill basket.
Websites and Resources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Fishbase fishbase.se ; Encyclopedia of Life eol.org ; Smithsonian Oceans Portal ocean.si.edu/ocean-life-ecosystems
Scombridae — the Mackerel and Tuna Family of Fish
Scombridae— a fish family embracing mackerels, tunas, and bonitos — includes some of the world’s most popular food and sport fishes. The family also boasts some of fastest-swimming of all fishes and some of the largest of all bony fishes. Scombrids’ speed and size are at least in part due to their high-energy metabolism, highly-evolved adaptation to a pelagic (open ocean) environment and their nomadic, constantly hunting existence. Their bodies are designed to maximize swimming efficiency. Tuna even have a vascular heat exchange system that them to swim for prolonged periods in colder water while their bodies remain warm [Source: Monica Weinheimer, Animal Diversity Web (ADW) /=]
Jack mackerel school Scombridae are mainly open ocean fish. Smaller mackerel often live closer to shore, but other mackerels, tunas, and bonitos range across deep waters, often following wide-ranging and complex migratory patterns. Some groups occur in brackish water, and one normally marine species, Scomberomorus sinensis, has been found in fresh water 300 kilometers up the Mekong River. Many groups within Scombridae tend to remain near the surface and over the continental shelf. /=\
The family Scombridae is comprised of two subfamilies, subdivided into 15 genera and 49 species. Tunas, mackerels, and bonitos can be found worldwide in tropical, subtropical seas, with many species traveling periodically into cool temperate waters. The fossil record for Scombridae dates back to the Lower Tertiary Period (66 million to 56 million years ago) and Lower Eocene Period (56 million to 47.8 million years ago). Due to their great range and extensive use as food fish, scombrids have many common names and are well-known to many groups of people. Bonitos, for example, were described in Captain Cook’s journals. Human influence — primarily overfishing — has caused at least five species to be listed as endangered or vulnerable to extinction.
Mackerel Physical Characteristics
Scombrids (tunas, mackerels, and bonitos) are endothermic (use their metabolism to generate heat and regulate body temperature independent of the temperatures around them) and heterothermic (have a body temperature that fluctuates with the surrounding environment).
According to to Animal Diversity Web: Scombrids have streamlined bodies that taper on either end, moderately large mouths, and well-developed teeth. Gill membranes are not attached to the isthmus. Scales are cycloid and usually tiny, and body coloration is metallic, often blue and silver. Spanish mackerels have yellow to bronze spots and bonitos and tunas may have dusky bands and fins. The dorsal fin is composed of 9 to 27 densely packed rays, and the pelvic fins have six rays. [Source: Monica Weinheimer, Animal Diversity Web (ADW) /=]
Scombrids are highly adapted to continuous swimming in the open ocean. Their bodies are an ideal streamlined shape, with the thickest part of the body occurring two-fifths of the way back from the head. Their dorsal fins can slot into grooves to reduce drag, and the caudal fin is stiff and sickle-shaped for powerful propulsion. The five to 12 separate finlets behind the anal and second dorsal fins may allow the tail to push against less turbulence by preventing vortices from forming in water flowing toward the tail. The slender caudal peduncle bears at least two keels that reduce drag and may accelerate water flowing over the tail.
Tunas have large hearts and blood volumes. They also have a high proportion of the red muscle that permits sustained swimming, buried centrally along the spinal column to conserve heat. Other members of the family, such as the mackerels, also have red muscle, but located nearer the outside of the fish. Butterfly mackerels keep brain and eye temperatures elevated using thermogenic (heat-producing) tissue. /=\
Mackerel Behavior, Feeding, Mating and Predators
Mackerel are motile (move around as opposed to being stationary), nomadic (move from place to place, generally within a well-defined range), migratory (make seasonal movements between regions, such as between breeding and wintering grounds), and social (associates with others of its species; forms social groups). [Source: Monica Weinheimer, Animal Diversity Web (ADW) /=]
Mackerel sense using vision, touch and chemicals usually detected with smell. Most are schooling fishes, but some can be found singly. They follow a nomadic lifestyle, sometimes engaging in regional migrations. For some groups, migrations may be determined by water temperature. Scombrids are continuous swimmers. Some species leap clear of the water when pursuing or escaping from prey.
Mackerel are active predators that feed on a wide range of organisms. The diet of a single species may include crabs, shrimps, squids, crustaceans, the larvae of fishes and invertebrates and fish. Some smaller species strain zooplankton through their gill rakers. Tunas often feed on mackerel. Some of the smaller mackerel species are food for a large number of predators, including a wide variety of fishes and seabirds. Mackerel of all sizes, including large ones are fed upon by large tunas, porpoises, dolphins, whales, seals other large fishes, and sharks.
Mackerel are iteroparous (offspring are produced in groups) and engage in seasonal breeding. Many species spawn repeatedly. Atlantic mackerel spawn all summer long. Female mackerels produce, on average, about half a million eggs, which float near the surface. Carried by the same current system as adults, mackerel larvae and juveniles grow rapidly and feed along with mature individuals. Atlantic mackerel eggs hatch in two to five days depending on the temperature. Mackerel can reach 24 centimeters (10 inches) in a year.
Pacific mackerel (Scientific name: Scomber japonicus) have about 30 dark wavy lines on their dark blue back and a light green , silvery underside. Also known as chub mackere and spanish mackerel, they have a pointy dark blue head and a large mouth. Their body tapers at both ends. Pacific mackerel can be distinguished from other mackerel by counting the finlets on their back; Pacific mackerel typically have four to six finlets. In the U.S. they can be found off West Coast Pacific mackerel grow fast, up to 63.5 centimeters (2.1 feet) and more than 2.7 kilograms (6 pounds). They can live up to 18 years but are able to reproduce by age four, and sometimes as early as age one. [Source: NOAA]
They spawn at different times of the year, depending on where they live. Pacific mackerel spawn from late April to September off California, year-round off central Baja California peaking from June through October, and from late fall to early spring off Cabo San Lucas. They spawn several times a year, releasing batches of almost 70,000 eggs each time. The eggs usually hatch within four to five days.
Pacific mackerel feed on plankton (tiny floating plants and animals) and the younger stages of all the pelagic species such as anchovies and sardines, as well as their own young. Various larger fish (such as sharks and tunas), marine mammals, and seabirds eat Pacific mackerel. Pacific mackerel school as a defense against predators. Often they will school with other pelagic species such as jack mackerel and sardines.
Pacific mackerel live within 32 kilometers ( 20 miles) of shore in water ranging from 10̊ to 22̊ C(50̊ to 72̊ F). When the population is small, they tend to occupy only the warmer part of their habitat. Juveniles live off sandy beaches, around kelp beds, and in open bays. Adults are found near shallow banks from the surface to waters almost 1,000 feet deep.. In U.S. water, Pacific mackerel are found from southeastern Alaska to Mexico but are most common south of Point Conception, California. As adults, they migrate north to Washington in the summer and south to Baja California in the winter. The northerly movement in summer is accentuated during El Niño events. They also travel inshore and offshore off California — they’re more abundant inshore from July to November and more abundant offshore from March to May..
Pacific Mackerel Fishing
In 2021, the commercial landings in the U.S. of Pacific mackerel totaled 900,000 kilograms (2 million pounds) and were valued at $480,000, according to the NOAA Fisheries commercial fishing landings database. Round haul nets are used to catch Pacific mackerel. Habitat and bycatch impacts are minimal because the gear is used at the surface. Recreational fishermen catch Pacific mackerel in California but seldom target them. The statewide recreational harvest makes up a small fraction (less than 5 percent in weight) of the total landings. [Source: NOAA]
U.S. wild-caught Pacific mackerel is a smart seafood choice because it is sustainably managed and responsibly harvested under U.S. regulations. Population: Above target population levels. Fishing Rate: At recommended levels. Habitat Impacts and Bycatch: The gear used to catch Pacific mackerel is used at the surface and has little impact on bottom habitat. Bycatch is low because gear used is selective. Population Status: Pacific mackerel is not overfished (2019 stock assessment), and not subject to overfishing based on 2020 catch data. Summary stock assessment information can be found on Stock SMART.
Pacific mackerel naturally experience “boom and bust” cycles of abundance, which is typical of other small pelagic species that have relatively short life spans and high reproduction rates. The Pacific mackerel stock is well above its target population level. However, in historical terms, the population remains at a relatively low abundance level, due primarily to oceanographic conditions. [Source: NOAA]
There is no directed fishery for mackerel in Oregon or Washington, but small amounts are taken incidentally by whiting trawlers and salmon trollers. NOAA Fisheries and the Pacific Fishery Management Council manage the Pacific mackerel fishery.under the Coastal Pelagic Species Fishery Management Plan: 1) Catch limits are in place to end and prevent overfishing. 2) Permits are needed to harvest Pacific mackerel. 3) Gear restrictions are in place to reduce bycatch.
Atlantic mackerel (Scientific name Scomber scombrus) are streamlined predatory fish that inhabit cold waters and continental shelf areas and migrate close to shore in the spring. They form large schools that feed on fish larvae and crustaceans. Spanning occurs in March to June, when individual females may lay as many as 450,000 eggs in a season.
Atlantic mackerel have a silvery white underside. The top half of body is iridescent blue green. Also known as mackerel, common mackerel, Boston mackerel and caballa, hey have 20 to 30 wavy black bars that run across the top half of their body, and a narrow dark streak that runs below these bars along each side. Their distinctive coloring fades quickly after they die.
Atlantic mackerel have a spindle-shaped, tapering at both ends. Their two large dorsal fins are gray or dusky. The pectoral fins are black or dusky at the base, and the tail fin is gray or dusky. Atlantic mackerel grow fast, up to 42 centimeters (16½ inches) and one kilograms (2.2 pounds). They can live up to 20 years and are able to reproduce by the time they reach age 2 to 3.
There are two major spawning groups of Atlantic mackerel in the western Atlantic: 1) The southern group spawns primarily in the Mid-Atlantic Bight from April to May. 2) The northern group spawns in the Gulf of St. Lawrence in June and July. Both groups typically spawn 16 to 48 kilometers (10 to 30 miles) off shore. Depending on their size, females can have between 285,000 and almost 2 million eggs. They release their eggs in batches, between five and seven times throughout the spawning season. Eggs generally float in the surface water and hatch in 4 to 7 ½ days, depending on water temperature.
Atlantic mackerel feed heavily on crustaceans such as copepods, krill, and shrimp. They also eat squid, as well as some fish and ascidians (sac-like marine invertebrate filter feeders). Several species of fish and marine mammals eat Atlantic mackerel.
Atlantic mackerel are found on both sides of the North Atlantic Ocean, including in the Baltic Sea. In the western Atlantic, they’re found from Labrador to North Carolina. Atlantic mackerel are common in cold and temperate waters over the continental shelf. They swim in schools near the surface, and travel to and from spawning and summering grounds.
Atlantic Mackerel Fishing
In the U.S., Atlantic mackerel are caught in New England, Mid-Atlantic and Southeast. In 2021, the commercial landings in the U.S. of Atlantic mackerel totaled 5.4 million kilograms (12 million pounds) and were valued at US$11 million, according to the NOAA Fisheries commercial fishing landings database. Massachusetts, New Jersey, and Maine harvested the majority of the fish.
Fishermen harvest mackerel in large volumes using mid-water trawls. The U.S. commercial fishery for Atlantic mackerel operates primarily between January and May in southern New England and Mid-Atlantic coastal waters and between May and December in the Gulf of Maine.
Although mid-water trawls have minimal impact on habitat, they can incidentally catch marine mammals such as short- and long-finned pilot whales, Atlantic white-sided dolphins, and common dolphins.
According to the 2021 stock assessment, Atlantic mackerel is overfished and subject to overfishing but the fishing rate established under a rebuilding plan promotes population growth. Fishing gears used to harvest Atlantic mackerel have minimal impacts on habitat. Regulations are in place to minimize bycatch.
NOAA Fisheries and the Mid-Atlantic Fishery Management Council manage the Atlantic mackerel fishery. Managed using annual catch limits allocated between the commercial and recreational fisheries. Fishermen must have a permit to harvest Atlantic mackerel. Managers limit the amount of available permits to control harvests and monitor commercial catch on a weekly basis and will close the fisheries if the limits are reached before the fishing season is over.
Under a limited access program, permits are issued to qualifying fishermen, dividing fishermen into three tiers based on their past participation in the fishery. This program is designed to reduce the fishing capacity of the mackerel fleet while allowing qualified vessels to continue fishing for mackerel at their historical or recent level of participation. A rebuilding plan to rebuild the stock to the target population level is in place with a target date of 2024.
The Atlantic Trawl Gear Take Reduction Strategy provides measures to reduce potential impacts of bycatch. These include outreach to educate fishermen about actions to take in the event of a marine mammal interaction and efforts to communicate interaction hotspots to fishermen in real time. It also contains voluntary measures concerning fishing practices, such as reducing tow times and limiting turns while fishing. The mackerel fishery has some incidental catch of river herring and shad. A cap was established in 2014 to limit river herring and shad catch in the mackerel fishery.
Mackerel are important to recreational fisheries in the Mid-Atlantic and New England regions, with the highest landings occurring from Massachusetts and Maine. In 2021, recreational harvest of Atlantic mackerel totaled 1.8 million kilograms (4 million pounds), according to the NOAA Fisheries recreational fishing landings database. The recreational mackerel fishery is open all year, with a catch limit set annually at the same time as commercial limits.
King mackerel (Scientific name: Scomberomorus cavalla) are iron-gray on the back and silvery on their sides and belly. Also known as cavalla, sierra, they have pale to dusky fins and sometimes have spots like Spanish mackerel, but king mackerel can be distinguished by their sharply dipping lateral line and gray anterior (near the front) dorsal (the upper side) fin. [Source: NOAA]
King mackerel grow fast, up to two meters (5 ½ feet) and 45 kilograms (100 pounds). They can live more than 20 years and are able to reproduce when they reach 2 years of age. They spawn on the outer continental shelf from May through October. Females release eggs in the open water, where they are fertilized. Females grow much larger than males, an evolutionary strategy that maximizes the amount of eggs that a female can produce. Females can produce 50,000 to several million eggs.
King mackerel are carnivores, feeding on fish, squid, and shrimp. They’re voracious feeders and have been observed leaping out of the water in pursuit of prey. Juvenile and larger pelagic fish feed on smaller king mackerel. Bottlenose dolphins and large fish, such as sharks and tunas, feed on adult king mackerel..
King mackerel are found in the Atlantic Ocean from Massachusetts to Brazil, including the Caribbean and Gulf of Mexico. There are two distinct populations in U.S. waters: one in the Gulf of Mexico and one in the Atlantic. King mackerel are a coastal pelagic species, meaning they live in the open waters near the coast. They live in water 35 to almost 185 meters (115 to almost 600 feet) deep. They prefer warm waters and seldom enter waters below 20̊C (68° F).
King mackerel migrate with seasonal changes in water temperature and with changes in food availability. They migrate to the northern part of their range in the summer and to the southern part in the winter, swimming in large schools. Both the South Atlantic and Gulf of Mexico stocks congregate in a winter mixing zone in an area of Monroe County, Florida, south of the Florida Keys, between November and March..
King Mackerel Fishing
In 2020, the commercial landings in the U.S. of king mackerel totaled more than 2.2 million kilograms (5 million pounds) and were valued at US$12 million, according to the NOAA Fisheries commercial fishing landings database. A large fraction of the commercial catch is harvested from the “winter mixing zone” in South Florida, which includes Gulf of Mexico and South Atlantic waters. Most commercial fishermen use hook-and-line gear such as handlines, rod-and-reel, and troll gear. Gillnets are also allowed in limited areas. Hook-and-line and gillnet gear have minimal impact on habitat because they do not contact the ocean floor. Fishing gear used to harvest king mackerel is very selective, so the fishery has little bycatch. [Source: NOAA]
Prior to the 1980s, king mackerel fisheries were essentially unregulated and became depleted. Regulations were implemented in 1983 to control harvest and rebuild declining stocks of king mackerel, and today these stocks have been restored to target population levels. There are two stocks of king mackerel: the South Atlantic stock and the Gulf of Mexico stock. According to the most recent stock assessments: Both the South Atlantic stock and Gulf of Mexico stock are not overfished and not subject to overfishing (2020 stock assessment).
U.S. wild-caught king mackerel is a smart seafood choice because it is sustainably managed and responsibly harvested under U.S. regulations. Above target population levels in the South Atlantic and the Gulf of Mexico. The fishing rate is at recommended levels in the South Atlantic and the Gulf of Mexico. Fishing gears used to harvest king mackerel have minimal impacts on habitat. Bycatch is low because hook-and-line and gillnet gear is selective.
NOAA Fisheries and the South Atlantic and Gulf of Mexico Fishery Management Councils manage the king mackerel fishery.under the Fishery Management Plan for the Coastal Migratory Pelagic Resources in the Gulf of Mexico and South Atlantic Region: 1) Commercial fishermen must have a permit to harvest king mackerel. 2) The number of available permits is limited to control fishing pressure on king mackerel. 3) Annual catch limits divided between the commercial and recreational fisheries for the Atlantic and Gulf of Mexico stocks. 4) Seasonal and per-fishing-trip limits. 5) Minimum size limit to allow fish time to mature and spawn. 6) Seasons for the Atlantic and Gulf of Mexico stocks. Seasons or areas can close early if quotas are reached. 7) Gillnets are prohibited in Florida state waters. They are also prohibited in federal waters, except seasonally in certain areas. 8) State regulations are fairly consistent with federal regulations.
King mackerel is a large, aggressive fish that is popular with recreational fishermen and makes up a large part of the total harvest. In 2020, recreational harvest of king mackerel totaled more than four million kilograms (nine million pounds), according to the NOAA Fisheries recreational fishing landings database. King mackerel support a valuable tournament fishery. Recreational management measures include: 1) Minimum size limits;. 2) Bag limits. 3) King mackerel must be landed with their heads and fins intact. Charter vessel/headboat operators must have a vessel permit for coastal migratory fish and must comply with possession limits.
Image Sources: Wikimedia Commons, NOAA
Text Sources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Wikipedia, National Geographic, Live Science, BBC, Smithsonian, New York Times, Washington Post, Los Angeles Times, The New Yorker, Reuters, Associated Press, Lonely Planet Guides and various books and other publications.
Last Updated April 2023