Tuna. What I ate for lunch every day in high school. What I ask for these days in sushi. And now there’s Wicked Tuna, a National Geographic series about the lives of Gloucester fishermen who pursue their livelihood in pursuit of these magnificent silvery fish. (Seeing them hooked, harpooned and decapitated might make a vegetarian out of me.) The series starts Sunday night on the National Geographic Channel and was previewed this week at the Wilbur Theatre, with many of the fishermen, friends and relatives in attendance.

The iconic images belie a troubled reality, with pressures coming for them on land and at sea. For the families involved in the pursuit, bluefin tuna are the defining element of their existence and the key to their economic survival. The series follows the struggles of five fishing boats, their captains and crews, revealing the stunning difficulty of their grueling work lives. There’s nothing high tech about the way they fish; it’s rod and reel, strength and determination. It costs about $3000 to provision a boat for a three-day outing on Georges Bank. They need to catch at least one fish just to break even, more than one if they’re small. Their language is salty, to say the least, and their anger at the elements or at each other is unconcealed. But underneath the “man talk” are a grittiness and entrepreneurial commitment to survive and succeed that is impressive.

Such stories are also the subject of a Regis College musical in April based on oral histories of the Gloucester fishermen’s wives. It will be at the college in Weston from the 11th to 14th and at the Cape Ann Theatre in Gloucester the 20th and 21st.

National Geographic’s stated goals are to tell the human stories behind the macro descriptions of the fishing industry and to educate people about the increasing scarcity of bluefin tuna. (According to its press material, the adult bluefin population has declined by as much as 83 percent in the Atlantic since 1950.) Marine biologists say it is a victim of overfishing. Governments have tried to set quotas for fish and regulate fishing methods, creating other problems for the fishermen.

But overfishing isn’t the only threat to Gloucester. Increasingly there are concerns about community gentrification and historic neighborhoods giving way to luxury development. Gloucester seems on the verge of solidifying the home of its 400-year-old fishing industry by marrying it to 21st century activities around marine innovation. It’s still a working class community, and one hopes it won’t become too precious as travelers and high rollers move in. Sadly, if gentrification goes too far, the real endangered species might turn out to be the Gloucester fishermen and families themselves.

I’d greatly appreciate your thoughts in the comments section below.