Looking at the bag of mackerel in my freezer, I was a little sad to think of not rebating our pair of lobster traps one last time. But, it was getting to be time to pull our boat out and to make the shift into what is officially now fall. At the same time, I got an email reminding me that October is National Seafood Month, an event promoting all types of seafood. It is a good reminder of the immense variety of seafood that we have in Maine. It is also a reminder not to overlook some of the underappreciated species – like fish we typically use as bait.

While the mackerel in my freezer might not make for a particularly delectable dinner as it has been salted in a bait barrel and has been sitting there for several weeks, fresh mackerel is one of my favorite simple summer dinners. Because it is an oily fish, like others including bluefish and sardines, it isn’t great if you don’t cook it right away. That’s the oils in the tissues begin to turn rancid and can lead to a bitter taste.

These oils, however, are the ones that are particularly healthy for you. Omega-3 fatty acids are the fish oil components that are most talked about. They help maintain a healthy heart and cardiovascular system by reducing inflammation. They’re also thought to reduce the risk of dementia. And oily fish also contains vitamins A and D that support a vital immune system.

So, to get these nutrients in a tasty way, the best way to cook oily fish is when it is super fresh. The oils in the fish crackle particularly well over a hot grill or when seared in a hot pan. You don’t have to do much to them – just add a little salt, pepper and a squeeze of lemon. They’re small enough that you can cook them whole. And, once they are cooked, you can use the meat in simple leftover dishes like fish hash with potatoes. Put an egg on top of that and you have a hearty breakfast or even dinner.

Aside from the fact that they are delicious, mackerel are among some of the most beautiful fish. Their rippled markings mimic light shining through the water — a perfect camouflage pattern. If you look at their bellies, however, they are shimmery white – this is to match the bright sky for any predators looking up from the depths. Coloration is just one of a mackerel’s tricks. Their fin design makes them incredibly efficient swimmers. A forked tail helps to easily push water back and forth, propelling them forward, and tiny finlets at the base of that tail help to streamline the flow of water along their backs.

I have learned their ins and outs first hand by dissecting them in multiple teaching situations. Some of what you discover in dissection is likely to be missing if you purchase fish for consumption. But, the eyeball is one that usually remains. What you see is a fluid-filled bright eye. Underneath, however, is a hard lens that looks like a tiny plastic round bead. It is round to gather and focus light from all directions under water – quite different than a human’s contact-shaped lens. Something you’re not likely to notice without dissecting a mackerel are its feathery gills. Pull open a mackerels gill covering and you will see layer after layer of gills designed with maximum surface area in order to absorb maximum amounts of oxygen from the water. These gills are also very dark red as is mackerel blood. That’s because it is very rich in iron – a critical component of red blood cells. Finally, they have a stealthy way of floating up or sinking down by inflating a tiny internal balloon called a swim bladder.

Getting back to the seafood connection. Mackerel also are filter feeders, which means they are low on the food chain. They also reproduce in great numbers. So, eating them is an environmentally responsible choice. If you don’t catch them yourself, you can get them super fresh at a few local seafood places. Or, you can also order them from Gulf of Maine Sashimi (gulfofmainesashimi.org) and pick them up each Friday at Turtle Rock Farm at Brunswick Landing. If you don’t choose to sample mackerel this month, at least you can appreciate that they aren’t just baitfish – they are impressive super swimmers (and maybe you’ll choose to work in a little more of your favorite local species this month).

Comments are not available on this story.