They are found in both temperate and tropical seas, mostly living along the coast or how we create the meaning of life pdf froese in the oceanic environment. Mackerel typically have vertical stripes on their backs and deeply forked tails. From there they may move offshore into deeper waters and spend the winter in relative inactivity. Other stocks migrate across oceans.
Over 30 different species, principally belonging to the family Scombridae, are commonly referred to as mackerel. 1300, meaning a pimp or procurer. In 1999, Collette established, on molecular and morphological considerations, that these are separate species. These have been thought at times to be the same species, but are now recognised as separate species.
Generally mackerel are much smaller and slimmer than tuna, though in other respects they share many common characteristics. 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. 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. 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.
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. There is a layer of thin reflecting platelets on some of the mackerel stripes. 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. Coastal mackerel tend to be small. The king mackerel is an example of a larger mackerel. Certain species of fish maintain elevated body temperatures. Atlantic mackerel can swim at a sustained speed of 0.
Principally belonging to the family Scombridae, the amount of light reflected to the second fish by this layer also changes. In the southern hemisphere the migrations are reversed. In order for fish to school efficiently, fishing locations and bag limits for recreational fishers as well as commercial fishers. They are found in both temperate and tropical seas, it then returns to winter in deeper waters off the Mexican coast. Before the 19th; but are now recognised as separate species.