Mackerel winter in deep water (approximately 300m) so leave our shores in the autumn, but they return to the shallows around the UK coast from April onwards to spawn. Mackerel, therefore, have to keep swimming to live, as if they stop moving forward they will drown. The mackerel has no such organ, as it uses a passive gill ventilation form of breathing, swimming along with mouth open and gill chambers expanded, so that water flows through the gills.

Alternatively, to swim downwards, they will release air from the swim bladder. If they want to swim upwards they will take air into the swim bladder to make themselves more buoyant. Many fish have a swim bladder, enabling them to stay stable in water and control the way they float. Actually, they are the fastest swimming fish in UK waters, able to swim around 50 metres in 10 seconds! In fact, they are such swift and manoeuvrable swimmers that they have no swim bladder, as the organ is not able to adjust quickly enough to rapid vertical movements. Mackerel are built for speed and, along with a highly forked tail, can streamline themselves by retracting their dorsal fin into a groove in their body when they swim. The UK shore caught-record, however, is 5lb 11oz! It is not a large fish, usually measuring in at around 12 to 18 inches in length and weighing about 1lb. It has a wonderfully exotic blue and green back, with around 20 black bars running down each side into the shiny silver underbelly.

The mackerel is a fast predatory fish, is closely related to the much larger tuna. Not only great fun, but probably the start of many a person becoming hooked on the popular sport of fishing!īut have you ever stopped to think a little about this abundant fish that we all perhaps take somewhat for granted? It is actually an amazing species of fish that really does warrant a little more attention and, dare I say it, respect. The good old mackerel ( Scomber scombrus) is often associated with summer holidays and something to do to occupy the family – a trip out on a small boat, for all ages to confidently catch a few to bung on the BBQ later. Ask the question, “Have you ever been fishing?” and regularly the answer will be, “Only once – a bit of mackerel fishing while on holiday!”

Macro fish being catched sketch