The term “mackerel” can mean different things to different people. Similar to sardines, the term “mackerel” refers to a group of fish as opposed to a singular species of animal. In 2009 alone, roughly six million tonnes of mackerel were counted in fisheries around the world. This is roughly the weight of the Pyramid of Giza!
There's a lot to learn about this delicious species, so let’s dive into the mackerel manual and look at some of its general qualities and different species in detail.
[Image by pasja1000 from Pixabay]
Mackerel Basics
The term “mackerel” generally refers to the roughly 30 species in the family Scombridae. While these species are varied, they have many different characteristics in common. All mackerel are considered “pelagic fish.” This means that they live neither close to the shore nor close to the bottom of the ocean. In other words, they live in “the open ocean.”
Mackerel Morphology
One of the most diverse morphological aspects of mackerel is their size. Generally, the family contains rather large fish. Smaller species, like the Pacific jack mackerel, may only be a few inches in size. Larger species, like the king mackerel, can weigh up to 100 pounds!
In terms of body shape, most mackerel are very similar, even if they are different sizes. Their bodies are thin and slim. One of the most noticeable characteristics is the presence of black stripes along the backs of most mackerel. These were thought to provide camouflage, but research had provided evidence otherwise. It seems that the dark stripes help the fish “school” together. Without the stripes, they may be more likely to lose each other while moving quickly in the water.
Behavior
Mackerel have very sharp teeth that they use to hunt other marine life. Their diet consists mainly of small fish, shrimp, and squid. On the other side of the predator-prey relationship, mackerel are the choice meal for tuna, pelicans, and sharks.
Distribution
Mackerel have an extremely wide distribution. Depending on the species, they can survive in both temperate and tropical waters. For example, Spanish mackerel occupy the area from New England to the Yucatan. Jack Mackerel live from the coast of Australia to the coast of Peru. We’ll dive further into each individual species' desired habitat below.
[Image by pasja1000 from Pixabay]
Types of Mackerel
As we discussed previously, there are roughly 30 species of fish that are generally considered to be mackerel. Let’s take a look at some of the most common ones that you may find for consumption.
Spanish Mackerel (Scomberomorus maculatus)
- Common names: The Spanish mackerel is also known as the spotted cybium, bay mackerel, or spotted mackerel.
- Distribution: These fish are found along the Atlantic coast of the United States as well as the Gulf of Mexico. The National Oceanic and Atmospheric Oceanic Administration (NOAA) recognizes two unique stocks (populations): the Gulf of Mexico stock and the South Atlantic stock.
- Appearance and Biology: Greenish back with silver sides and belly. They can grow up to 13 pounds and live to be 12 years old.
- Conservation: As of 2013, mackerel make a fantastic choice for sustainable fish consumption as the NOAA rates their fish stock levels as “over target population.”
King Mackerel (Scomberomorus cavalla)
- Common names: The king mackerel is also known as the cavalla or Sierra mackerel.
- Distribution: The extant range of king mackerel is similar to the Spanish mackerel, only larger. King mackerel can be found along the Atlantic coast of the Americas from Massachusetts to Brazil.
- Appearance and Biology: This species is named “king” for a reason. They can grow to be over five feet long and weigh more than 100 pounds! King mackerel are iron-gray on the back and silvery on their stomach and sides. Infrequently, they may carry spots, as well.
- Conservation: As of 2014, king mackerel make a fantastic choice for sustainable fish consumption as the NOAA rates their fish stock levels as “over target population.”
Atlantic Mackerel (Scomber scombrus)
- Common names: These mackerels are also known as the common mackerel, Boston mackerel, or caballa mackerel.
- Distribution: The Atlantic mackerel has a much narrower distribution than either the Spanish or king mackerels. These fish live primarily in the northern part of the Atlantic Ocean, on both sides. On the American side, they exist from southern Canada to North Carolina. On the European side, they exist around English territorial waters as well as in the Baltic Sea.
- Appearance and Biology: Atlantic Mackerel are much, much smaller than their south Atlantic counterparts. Typically, they will only reach about 1.5 feet in length and can weigh up to two pounds.
- Conservation: As of 2018, Atlantic mackerel are classified as “overfished.” This means that the population is significantly below target levels, and there is a plan in place to increase the species' numbers.
Jack Mackerel (Trachurus symmetricus)
- Common names: The jack mackerel is sometimes referred to as the Pacific Jack Mackerel, but this can be rather confusing as the Pacific mackerel (Scomber japonicus) is also a species.
- Distribution: These mackerel are found in the northern and eastern parts of the Pacific Ocean, primarily from Alaska to Baja California. Recently, populations have been noticed in larger numbers in the Gulf of Mexico.
- Appearance and Biology: Like Atlantic mackerel, jack mackerel tend to be smaller. They will grow to about two feet in length and weight just under three pounds.
- Conservation: Jack mackerel are listed as “least concern” on the IUCN Red List. In the 1980’s, there was evidence of overfishing, but populations have recently stabilized.
Atlantic Horse Mackerel (Trachurus trachurus)
- Common names: Sometimes just called "horse mackerel," this species is also known as European horse mackerel. Interestingly, it's actually a species of jack mackerel, in the Carangidae family.
- Distribution: Horse mackerel live mostly in the northeast Atlantic Ocean, although some can be found as far south as the Cape of Good Hope in South Africa.
- Appearance and Biology: Similarly to jack mackerel, horse mackerel are quite small. They grow to be just under two feet long, and weigh around 3 pounds.
- Conservation: unlike jack mackerel,however, Atlantic horse mackerel is listed as vulnerable on the IUCN Red List. This is largely due to overexploitation in areas like Mauritania and failed conservation efforts in the Mediterranean Sea.
Atlantic Chub Mackerel (Scomber colias)
- Common names: The particularly small chub mackerel are sometimes called 'tinker' mackerel.
- Distribution: Atlantic chub mackerel live throughout the Atlantic Ocean, although different stocks are noted in different areas (eg. the northeast atlantic population is not the same as the one in the southwest), as well as the Black Sea. The species is particularly abundant, however, in the southern part of the Mediterranean Sea.
- Appearance and Biology: This species is also on the smaller side amongst mackerel, growing to be only about 14 inches long, at most.
- Conservation: Atlantic chub mackerel is listed as a species of least concern on the IUCN Red list, meaning the populations have enough time to replenish themselves given the rate at which they are fished.
It's never a bad idea to know a bit more about what you're eating. So next time you're perusing your local fish market or eating delicious tinned mackerel, you'll know just where it came from.
Article written by Patrick O'Hare on October 7, 2020.
Cover image by Wolfgang Eckert from Pixabay.