If you are a ‘bigmouth’ don’t be proud of yourself, unless… you’re in the ocean!
Encountering mackerels is almost as exciting as encountering manta rays, partly because manta rays will follow shortly after.
Mackerels move in big schools and when feeding on the surface you can definitely hear them approaching. The water will appear to boil from above and and when seen from under the water it seems like piranha are coming to get you. But don’t worry, although their jaws open widely to reveal their gaping mouths, mackerels feed on plankton!
They move in an orderly manner, in big school. The amazing black stripes on their back are one of the key to their organization, together with their sixth sense, the lateral line. Each fish perceives the change in direction and speed of the group by looking at its neighbour and also feeling its movement through the pressure waves caused by sudden changes of acceleration.
Fish tend to aggregate by size so that they do not compete with each other. When feeding in Hanifaru Bay, the density of plankton is so high that mackerels can afford to use the energy consuming method of filter feeding with mouth and gills open, which gives them their scaring and fascinating appearance.
Bigmouth strikes again and it’s worth witnessing it!