PORTSMOUTH, N.H. – Henry Lovejoy is a fishmonger for the 21st century.

Unlike his seafood peddling forebears, he doesn’t offer just any old catch of the day. But it isn’t his use of the Internet, overnight shipping and flash freezing that makes EcoFish so nouveau.

Lovejoy’s 8-month-old seafood distribution company helps people make meals that reflect their morals.

EcoFish is a rare breed because, unlike most distributors, it offers only sustainably harvested fish, the seafood equivalent of organic fruits and vegetables.

“There is a very strong movement in this country to sustainability,” Lovejoy, 37, said in a recent interview. “It’s evidence that more and more consumers are becoming more and more concerned about their food and where it came from.”

Though definitions of sustainable vary, it generally refers to seafood caught or raised in ways that won’t deplete stocks and are sensitive to the environment. Sustainable practices can include limits on species and amounts caught.

The movement mostly is driven by consumer demand – the desire to support eco-sensitive practices. It first became an issue during the 1970s when consumers wanted their tuna to be “dolphin-safe.”

Conservationists say conventional fishing practices, such as trawling and fish farming, can endanger species and harm the environment. Many fish farms, for example, treat their fish with hormones and antibiotics, practices that would not be considered sustainable.

Lovejoy and his wife, Lisa, got into the seafood industry after college, when they started an export business that shipped live lobsters around the world. However, the longer they were in the business the less they liked how it was conducted.

Fishermen have long wrangled with government and conservation groups over how best to ensure that seafood is not over-harvested. This creates a financial tug-of-war that pits jobs against the environment.

Susan Boa, spokeswoman for the Seafood Choices Alliance in Washington, D.C., said fish are losing the battle. She said more than 100 species in U.S. waters are overfished and could risk extinction.

Meanwhile, the short supply and efforts to limit fishing also make it difficult – some say impossible – for fishermen to earn a living. Conservationists say the solution is to use sustainable practices, which preserves jobs and fish stocks.

“We want to have fisheries around,” Boa said. “We want to be able to enjoy the wide diversity of fish that we’ve all come to know and love, and not be forced into narrow choices because we’ve driven things to the point where fisheries no longer exist for them.”