Delacroix Island fisherman Thomas Gonzales hunts nutria in 'Rodents of Unusual Size.'

Delacroix fisherman Thomas Gonzales would rather collect crabs and hunt alligators, but between seafood seasons, he hunts nutria. Though it’s edible, he doesn’t eat the meat. He collects $5 per tail from the Louisiana Department of Wildlife & Fisheries’ Nutria Control Program. Many registered participants supplement their income by battling the invasive species for the state.

Nutrias’ prolific reproduction rate is the source of both the problem and the work, but Gonzalez would be better off without the swamp rats. Gonzales’ predicament is at the heart of the documentary Rodents of Unusual Size, from filmmakers Chris Metzler, Quinn Costello and Jeff Springer. The film screens Aug. 24-30 at Zeitgeist Multi-Disciplinary Arts Center.

Nutria, the orange-toothed creatures that devour vegetation in swamps, marshes and canals, have thrived in Louisiana since their introduction and release into the wild in the 1930s. Their population is believed to have topped 25 million in the 1970s. That the New Orleans Zephyrs (now named the Baby Cakes) minor league baseball team chose the rodent as a mascot suggests locals’ begrudging acceptance if not embrace of the animals’ place in our landscape. The documentary is clear that the species presents a serious problem by accelerating coastal land loss, but the film explores the way people in South Louisiana have come to live with the contradictions of their presence.

By eating vegetation, particularly plant roots, and burrowing in the ground at the waters edge, nutria accelerate the loss of wetlands and eat away at canal banks and every environment they inhabit. They have spread elsewhere in North America and also are now a nuisance in Asia and Europe. In South Louisiana, they contribute to another serious problem: exposure to hurricanes and storm surge. As fishing communities struggle to survive amid changes in fisheries and loss of coastal land, nutria are one more threat to their homes.

Much of the film features beautifully shot views of swamps and bayous. But the film also follows the creatures inland, documenting control efforts in canals in New Orleans and a golf course in Kenner. The swamp rats are so common that they have fans as well — one man who keeps a large nutria as a pet fashioned a plastic container so it can ride on the back of his motorcycle.

For decades, trappers and hunters kept the nutria population in check, but when fur fell out of fashion, it ballooned. The Wildlife and Fisheries control program paid hunters for a total of 170,500 nutria tails last year, according to its website. The state also tried to build a market for nutria meat. Chef Susan Spicer and musician Kermit Ruffins cook nutria in the film, but diners are reluctant to try it. The Righteous Fur group holds periodic nutria fashion shows and sells hats and other items.

Rodents of Unusual Size is narrated by Wendell Pierce (The Wire, Treme) and features music by the Lost Bayou Ramblers. Scenes of a second line and Ruffins talking about how Hurricane Katrina affected him seem tenuously connected to the subject but may provide more familiar cultural and geographical links for some viewers. Stories shared by fishermen and scenes in coastal Louisiana, however, are worth viewing, even for those familiar with the area or nutria.

Filmmakers and guests participate in Q&A sessions after screenings Friday through Sunday. Nooty the Nutria, a “stunt nutria” who appears in the film, will be at the Saturday screenings.

Tickets $10. At 6 p.m. and 8 p.m. Aug. 24-30. Zeitgeist Multi-Disciplinary Arts Center, 1618 Oretha Castle Haley Blvd., (504) 352-1150;